Synthesis, characterization, and reactivity of palladium amido and nitrene complexes

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Title:
Synthesis, characterization, and reactivity of palladium amido and nitrene complexes
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xiv, 275 leaves : ill. ; 29 cm.
Language:
English
Creator:
Villanueva, Lawrence A. Jr., 1966-
Publication Date:

Subjects

Subjects / Keywords:
Complex compounds   ( lcsh )
Organometallic chemistry   ( lcsh )
Chemistry thesis Ph. D   ( lcsh )
Dissertations, Academic -- Chemistry -- UF   ( lcsh )
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bibliography   ( marcgt )
non-fiction   ( marcgt )

Notes

Thesis:
Thesis (Ph. D.)--University of Florida, 1993.
Bibliography:
Includes bibliographical references (leaves 260-274).
Statement of Responsibility:
by Lawrence A. Villanueva.
General Note:
Typescript.
General Note:
Vita.

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University of Florida
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All applicable rights reserved by the source institution and holding location.
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oclc - 31200893
notis - AKC7448
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Full Text









SYNTHESIS, CHARACTERIZATION, AND REACTIVITY OF PALLADIUM
AMIDO AND NITRENE COMPLEXES














BY


LAWRENCE A. VILLANUEVA, JR.


A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY

























To my family













ACKNOWLEDGEMENTS


There


are many


people


are directly


well


as indirectly


responsible


research


reported


dissertation.


The


author


expresses
Boncella


special


appreciation


support,


wisdom,


gratitude


advice


Professor


preparation


dissertation.


Under


direction


Boncella,


author


become


a competent


scientist


ready


to accept


new


challenges


well


as outside


laboratory.


Special


explain

solved


thanks


facets


to Dr.


X-ray


structures


Khalil


Abboud


crystallography


to the


dissertation


taking

author.


time


Abboud


author


grateful


The


author


patience
wishes


enthusiasm.


express


sincere


appreciation


Gaines


Martin


Scott


Gamble


their


support


advice


early


years.

Lende,


Eternal

William


gratitude

Vaughan,


goes t

Mary


o Dr.


Laura


Cajigal,


Blosch


Percy


Daniel


Doufou


Vander


Jerrold


Miller,


Tegan


Eve


, Barry


Rickman


Roth


providing


a friendly


productive


atmosphere


laboratory.


The


author


is forever


ebted


to Don


Eade


Julie


Malham


their


encouragement


support


outside


laboratory


Special














TABLE OF CONTENTS


ACKNOWLEEMENTS ................ ... ..... .................................... ......................1ii

LIST OF TABLES ....................................................................................................... viii

LISTOF FIGURES .........E............................................................................................ ix

ABSTRACT................................................................................................................... xx

CHAPTERS


INTR ODU C I ON ................................................................................................ 1


Preparation


Late-


Transition-Metal


Amide


Complexes


Late-


Transition-Metal


Catalysts for the
An Investigation


Amide


Amination


Complexes
Olefins......


Palladium(II)


Amide


Complexes


General Considerations....


Synthesis and
Preparation


Characterization


[C6H4C(H)=NPrl)Pd(PMe3)3][BF41 (4).........................................2 0


Preparation of
[C6H4C(H)=NPh)Pd(PMe3)3] [BF4] (5


Preparation


trans-


(PMe3)2Pd(C6H4C(H)


Addition


=NPr1)(NHPh)


CH3I to trans-


(PMe3)2Pd(C6H4C(H)


Preparation


=NPr')(NHPh)


0..0..0..0... ....''''''........... 2


trans-


/DAlKLa DA / -rU A UiI\-TD (/KTI-TDl


tin,


,


.................................. 2


) ................... ................... 2


Overview .................. .................. ..


~XPERIMENTAL ................... ................... ................ ..~. ................... ................ 18


\


II








Preparation of trans-(PMe3)2Pd(C6H4-pOCH3)(NHPh)
(18 ) ........................... .. ................................................................ 2 3
Preparation of trans-(PMe3)2Pd(o-NH2-C6H4)(NHPh)


(19) ................ .................2................................. ............................ 2 3


Preparation of
(PMe3 )2Pd[
Preparation of
Addition of An


trans-
CH=C (H)C6H 5 ](NHP h)(2 1)..............................
trans-(PMe3)2Pd(CH3)(NHPh) (23)................
line to cis-Pd(PMe3)2(CH3)2.............................


Preparation
Preparation
Preparation


trans-(PMe3)2Pd(Ph)[N(Me)Ph] (26
trans-(PMe3)2Pd(Ph)(NPh2) (27)...
trans-(PMe3)2Pd(Ph)(NH-2,6-iPr2-


) ............ 2 5


te fl***....flt**


Pre


C6H3) (28).............................................................................................. 2 6
paration of trans-(PMe3)2Pd(Ph)(NHPh-pCH3)
(29) .............................................................................................................2 6


Preparation of trans-
(PMe3)2Pd(C6H4C(H)=NPh)(NHPh-pCH3) (30) ...................2 7
Preparation of trans-
(PMe3)2Pd(C6H4C(H)=NPh)(NC4H4) (31).................................. 2 7


Preparation
Preparation
Addition ol
Preparation
Preparation
(36) ......
Thermolysi
Preparation
Preparation
Preparation


Pre


of [(PMe3)Pd(Ph)( p-NHPh)]2 (32).........................2 8
of [(PMe3)Pd(CH3 )(g-NHPh)]2 (34) ...................... 2 8
F PMe3 to Compounds 32 and 3 4 ................................2 9
of trans-(PMe3)Pd(C6H4CH= NPri)I (37) ............2 9
of [(PMe3)Pd(C6H4CH=NPri)(L-NHPh)
.................................................................... .......................... .. .2 9
s Studies ........................................................ ............... 3 0
of cis-(PMe3)2Pd(CH13)(NHPh) (38)......................... 30
of [(PMe3)Pd(CH3)(pg-CH2PMe2)]2 (40)..............3 1
of trans-(PMe3)2Pd(Ph)[OC(O)NHPh] (42).........3 1


paration of trans-
(PMe3)2Pd(Ph)[OC(O)C(H)C(H)C(O)NHPh] (43).................. 3 2


Preparation of trans-
(PMe3)2Pd(Ph) [N(Ph)C(O)C(H)Ph2] (45) ............................... 3 2


Preparation of trans-(PMe3)2Pd(Ph)lN (Ph)C(0U)lN H(t-
Bu)] (47).............................................................................................. 3
Preparation of trans-(PMe3)2Pd(Ph)[N(Ph)C(O)NH-2,6-
iPr2-CH3](48).................. ......................................................... 3


2

3








Preparation


trans-


(PMe3)Pd[(MeOOC)C=C(COOMe)(NHPh)](Ph) (50)..................3 4


Preparation


trans-


(PMe3)2Pd [(MeOOC)C=C(COOMe)(NHPh)]


(C6H4C(H)=NPh) (51


)........................................


Preparation o:
Magnetization
Preparation of


Transfer


ind 51-15N ..........
Experiment for


trans-(PMe3)2Pd(o-NH2


50............


-C6H4)


(CH302CC=C(CO2CH3)NHPh) (52)..........


Preparation


trans-


(PMe3)2Pd(C6H4C(H)


Thermolysis


dimethylcarboxylate


=NPh)(CCO


Generate


2Me) (54).......


-anilino-


-2-phenylethylene


(55).....................38


Thermolysis


Generate


-phenyl-


1-anilino-


-dimethylcarboxylate-


) .....a.. IeO...i..Q.O... .... .. O. Q.... .. .. .......


Preparation


,2-dihydroisoquinoline)


[Pd(PMe3)3 I] [BF4] (57)


[Pd(PMe3)2(THF)I] [BF4] (59)...


Preparation of Me3P


=NPh-H2NPh (58)... .......


Preparation
Preparation
Preparation
Preparation


Me3P=


15NPh*H21


NPh.......


of 58 in the Presence of PEt3....


Cy3P


Me3P


=NPh


=NAr-H2NAr


=2,6-diisopropyl


phenyl)


) ... t.... O... ........ ...g.Q.. .....


Preparation of (Me3P)2Pd


Preparation
Thermolysis


(Me3P)2Pd


Studie


-3.5


-(CF3)2


-C6H3 (65)


6 5.....


Addition of PMe3 to 63.


Addition


Water


to 63


X-ray Structure Determination................
Addition of HC1 to 65................. .................
SpectroscopicData...........................................


SYNTHESIS AND CHARACTERIZATION OF
PALLADIUM(IH) AMIDE COMPLEXES........


a S S


, --


-AU- :- --- -


- -,,l, L!- A ---A


-a


~I,,,,,,S


6 5.........


(61).....,


NCgFg (63)








and Ne
Synthesis
Phenyl,


Sutral
and


Palladium(II)
Characterization


Vinyl,


Alkyl


Complex es ................. ................... 7 9


I


Palladium(


Substituted
II) Amide


The


Effects


Structure


Ancillary


Ligands


Palladium(II)


on the
Amide


Stability


Complexes.......


Selection


Amide


Reagents ..............................


Synthesis,


Characterization,


Dimeric


Palladium(II)


X-ray


Amide


Crystal


Complexes


Thermolysis Reactions................


Analyses


107
119


Synthesis


And


Reactivity


of cis-(PMe3)2Pd(CH3)(NHPh)....
Conclusions................................................


124
139


REACTIVITY OF PALLADIUM(II) AMIDE COMPLEXES ...............143


Reactivity


Palladium(II)


Amide


Complexes
. .. ... ... .. .. ... .. ..... .. ... .. ... .....I1


with Electrophilic Substrates...........


Mechanistic


Studies


Insertion


Addition


Reactions...............


............................. 1 5 2


Reactivity


with


Palladium(II)


Activated


Acetylen


Amide
es.........


Complexes


Thermolysis Reactions........... ................................
Summary and Conclusions......................................... .


158
174
179


PREPARATION OF PALLADIUM NITRENE COMPLEXES ...............1 8 1


Introduction
Attempts to
Stabilization
Conclusions


Transition-Metal


Prepare


Palladium


Palladium


Imido


Imido


Nitrene


Complexes..........


Complexes............


182
192


Complexes ..................


..... ....... ..l. ... .... e ....... .. .. ...* ... SS **.. .. *.**.*. *** ***** **** ** *t*


APPENDIX ................................................................................................................ ...2 2 1

LIST OF REFEREN CES.............................................................................................2 6 0

BIOGRAPHICAL SKETCH .......................................................................................2 7 5


0000..... 0.... 00.. ......0... 0... 0"...... ''......... 8


.............2


............2


C om pie re s ................... ................... ..













LIST OF TABLES


Table 2.1

Table 2.2

Table 2.3


1H NMR

13C{ 1H)


D ata........................................................................................ 5 3

D ata .................................... ................................................. 6 0


31p{lH} Data..........................


Table


Selected bond lengths


and angles


for 4 .......................7 6


Table


Selected


bond


lengths


and angles


15.................. 8 5


Table


Selected


bond lengths


angles


32.................1 1 0


Table


Selected


bond


lengths


angles


33.................1 13


Table


Selected


bond lengths


angles


Table 4.1


Selected


bond lengths


and angles


for 50.................1 60


Table


The


experimental


theoretical


isotope


distribution


*5*** *. **..*.........2


63......................... ...S......... ..............................................


111111111~~(11(11))1)(l))l)l(lllrrl)())( 6


40................. 136













LIST OF FIGURES


Figure 1,
amide


Possible


bonding


complexes.


geometries


transition-metal


........... .a..... ....OQ... D.... .Q.f ....fteme........m...'.....****..***** 3


Figure


Orbital


interaction


between


lone-pair


electrons


nitrogen


the d-orbitals


metal


center.


Figure


Stoichiometric


addition


an anumne


a coordinated


Figure 1.4.
nucleophilic


Catalytic
attack c


cycle


an amine


amination


on a coordinated


an olefin


way


olefin.


Figure
N-H


Catalytic


4


oxidative addition


cycle
to a


amination


an olefin


way


transition-metal.


Figure


The


synthesis


Figure

Figure


The

The


thermal

1H NMR


ellipsoid

spectrum


drawing


of 9 in C6D6 at 25 C.


Figure


1H NMR


spectrum


of 15 in C6D6 at 25 OC.


Figure


The thermal ellipsoid plot of 15.......................................... 8 7


Figure

Figure


The

The


1H NMR

1H NMR


spectrum

spectrum


of 21 in C6D6 at 25 OC.

of 23 in C6D6 at 25 C.


Figure


1H NMR


spectrum


of 26 in C6D6 at 25 OC. ..........100


Figure


3.9.


The


1H NMR


spectrum


of 28 in C6D6 at 25 C.


..........103


............8 6


............ 9 1

............ 9 3


olefin. ........................................








Figure


3.12.


Possible


isomers


32 (R


= Ph) and 34


= CH3).


113


Figure


3.13.


The


thermal


ellipsoid


drawing


Figure


3.14.


1H NMR


spectrum


of 34 in C6D6 at 25 OC.


........ 1 1 7


Figure


Figure

Figure


3.15.


3.16.

3.17.


Proposed


The

The


mechanism


1H NMR


NMR


and 39 in C6D6 at 25 OC.......


spectrum

spectrum


formation


of 38 in C6D6 at 25 OC.


equilibrium


...........127


between


129


Figure


3.18.


1H NMR


spectrum


of 38 in C6D6 at 90 OC............13 1


Figure


3.19.


The


NMR


spectrum


of 38 at (a) 25


C and (b) 80 OC.


d8 -toluene.


.... .. ...... .S .......... .. .. ... .. a. .' Q '.... .... .'... ... ... .'.'.... .S...... ......'...."


132


Figure


Figure


3.20.


3.21.


The


The


NMR


thermal


spectrum


ellipsoid


40 in C6D6 at 25 C.


drawing


..........137


..........................1 3 8


Figure


The


1H NMR spectrum


CDC13 at 25 OC.


Figure


The


1H NMR spectrum


43-15N


CDC13 at 25 C.


148


Figure


The


in C6D6 at 25 C.


phenyl


region


NMR


spectrum


SC CS S-*e*C **SS Sf~lllllll l l f lll lf l


49-15N
......... 154


Figure


The


1H NMR


spectrum


15-15N


PhNCO


at (a)


C (b) -30 C and (c) 0 C in d8-toluene.


154


Figure
label


Mechanism


compound


statistical


distribution


55~l****e* .f~ll. ***SI*O ****fl.. ......*******.........


................15 5


Figure


The


NMR


spectrum


C and (b) 25 C in d8-toluene.


of 15-15N


tBuNCO


at (a) 0


....156


Figure


Mechanism


insertion/addition


reactions


".7


- 2.. I. 1L. Z- -L ...i


.........146


11111)11)111111)()1((tl(l((ll()((l)))()(


15N








Figure 4.9. The thermal ellipsoid drawing of trans-
(PMe3)2Pd(Ph)[(CH3COO)C=C(COOCH3)(NHPh) (50). .........................1 6 2


Figure


4.10.


The


proton


difference


nOe


enhancements


....163


Figure


4.11.


1H NMR spectrum of 51 in


CDCl3 at 25 OC.


.........165


Figure


4.12.


Magnetization


transfer


experiment


.................1 6 8


Figure


4.13.


The


difference


spectrum


magnetization


transfer


experiment.


...........169


******Se******S*S****t**t****************f


Figure 4.14.


plot of In(H1i


+ H2)/(H1-H2)


vs time(t)


with


a slope


of 2k.


..... .............................. ................ ............... ................ a.. *****... **.......**...


....169


Figure


4.15.


carbon-carbc


Proposed
in double


mechanism


bond


and 52


isomerization


= PMe3;


C(H)=NPh, NH2).


0**.........00..0*..0.....0...00SSS *.....000.0"'0*0.'.......e...**............


................. 1 7 0


Figure


4.16.
amido


The


group


zwitterionic
to DMAD


intermediates


methyl


from


2-butynoate.


addition


171


Figure


4.17.


bond


Mechanism
palladacycles.


insertion


acetylenes


into


176


Figure


4.18.


1H NMR


spectrum


of 56 in C6D6 at 25 OC.


Figure 5.1.
complexes.


Modes


bonding


transition-metal


imido


.........................1 83


Figure


Oxygen


transfer


to substrate


P-450


by cytochrome
..............................................1


Figure 5.3.
analogue


Nitrene


transfer


cytochrome


to cyclooctene


P-450.


utilizing


................ 1 8 8


Figure 5.4.
phosphines


The


catalytic


generate


cycle for for
phosphinimines.


nitrene


transfer


tertiary


Figure


Orbital


diagram


ML2


fragments.........195


................. ........._.19 O








Figure 5
metal


Figure

Figure


Orbital


interactions


between


imido


ligand


center.


5.9.

5.10.


Possible me

Stabilization


ichanisms


a Fischer


phosphinimine


carbene


formation.


p-donation


203


form


lone-pair


electrons


a heteroatom.


............................2 0 5


Figure


5.11.


ligand


atomic


Energy
metal
orbital


diagrams


center


respectively


d orbitals
: relative


changes.


of the imido
energies of
.......................2 C


Figure


5.12.


Proposed


mechanism


formation


=PMe3


from


addition


H20


a palladium


nitrene


complex.













Abstract


Dissertation


Presented


Graduate


School


University


Requirements


Florida


Partial


Degree


Docte


Fulfillment
or of Philo


'sophy


SYNTHESIS, CHARACTERIZATION,


AND REACTIVITY OF PALLADIUM


AMIDO AND NITRENE COMPLEXES

By


Lawrence


Decembi


Villanueva,

er, 1993


Chairman:
Major De


James


apartment :


Boncella
Chemistry


The


synthesis


characterization


variety


monomeric


palladium(II)


neutral


monomeric


amido


cationic


amide


complexes


palladium(II)


complexes


addition


complexes


air-


amide


presented.


moisture-


reagents


The


sensitive


however


The


, they


nature


are stable


amide


solid


reagent,


state


ancillary


solution


ligands


at 25


coordinated


metal


center,


ubstituents


on the


amido


group


metal


center


influence


overall


stability


palladium(II)


amide


complexes.


Thermolysis


studies


several


monomeric


amide








The


reactivity


monomeric


amide


complexes


with


unsaturated,


electrophilic


substrates


was


investigated.


The


crystal


structure


trans-(PMe3)2


Pd(Ph)(NHPh)(15)


revealed


that


lone-


pair


amide


electrons


complexes.


nitrogen


control


Compound


reactivity


readily


palladium(II)


inserts


maleic


anhydride


into


Pd-N


bond,


while


N-H


bond


across


C-C


double


bond


diphenyl


ketene


C-N


double


bond


tert-butyl


temperature
information


2,6-diisopropylphenyl


N-labeling


about


these


experiments


reactions.


The


isocyanate.


provided


reactivity


Variable


mechanistic


palladium(II)


amide


order


complexes

to determine


with


activated


potential


acetylenes


these


was


also


omple


investigated


to facilitate


C-N


bond


formation.


Attempts


prepare


molecules


with


Pd-N


multiple


bonds


was


investigated.


The


addition


equivalents


KNHPh


[Pd(PMe3)2(THF)I] [BF4]


resulted


reductive


elimination


phosphinimine


formation.


The


generation


a palladium


nitrene


complex


was


believed


responsible


phosphinimine


formation.


order


stabilize


reactive


nitrene


intermediate,


amide


reagent


with


electron-withdrawing


groups


were


investigated.


The


addition


equivalents


of KNHC6F5


KNH


-3.5


-(CF3)2


-C6H3 to trans-Pd(PMe3)2


2 generated


stable


nitrene


complexes.


The


reactivity


these


complexes


with


PMe3


H20


was


similar


that


previously


reported


transition-metal













CHAPTER 1
INTRODUCTION


Overview


The


extensive


complexes


KNH2)


synthesis


preparation


research


prepared


early


amide


metal


amide


over


were


those


nineteenth


complexes


complexes


century.

sodium ai

century. 1


involving


The


been


first


focus


amide


potassium


Since


majority


(NaNH2


then


main-


group

amide


elements


complexes


been


with


firmly


respect


established,


to reaction


chemi


utility


metal


been


subject


a comprehensive


review.2


While


been


established


preparation


literature


main-group


amide


preparation


complexes


amide


complex


involving


transition-metal


amide


transition-metals


complex


still


defined


being

any


developed.


pnmary


secondary


amine


transition-metal.


with


first


substituents


example


on nitrogen


transition-metal


being

amide


complex


was


prepared


addition


NaNPh2


TiC14;3


however


was


until


early


sixtie


that


transition-metal


amide


chemistry


truely


emerged.


The


most


common


route


trans


ition-


rrL,


a- ---- n a a S nfl C


A


rn ntr Es,


'I


Inn


* |


I_


1


CT


|








M-X


NRR'


M-NRR'


approach h

following

lanthanide


reactions


to the


transition-metals:


preparation


groups


actinides.21


most


common


route


amide


3 -7.4-14


Although

to metal


compounds


Fe,15


transmetallation


amide


complexes,


other


approaches


exist


discussed


below).


important


observation


with


respect


transition-metal


amide


complexes


is that


majority


these


complexes


involve


early-transition-metals.


Indeed


, as


one


proceeds


towards


right


transition


series


number


characterized


amide


complexes


decreases


are especially


dramatically


uncommon.


One


. Those


possible


, Co,


explanation


triads


scarcity


late-transition-metal


amide


complexes


involves


bonding


amido


group


to the


metal


center.


monomeric


transition-metal


amide


complexes,


there


are two


bonding


possibilities


(Figure


1.1).


first


planar


bonding


with


mode


hybridization.


geometry


This


about


geometry


nitrogen


implies


is trigonal


there


significant


x -donation


from


electron


pair


on nitrogen


to the


metal


center


(Figure


1.2).


The


geometry


about


nitrogen


is trigonal


pyramidal,


suggesting


hybridization


localization


electron-pair


nitrogen.


ability


transition-metal


center


accommodate


lone-pair


electrons


amido


nitrogen


through


x -donation


that















0 0


Figure


Possible


0 *


vs


bonding


geometries


transition-metal


amide


complexes.


Figure


Orbital
nitrogen


interaction


between


d-orbitals


lone-pair


metal


electrons


center.


~FUUWr*""








been


demonstrated


experimentally


that


there


significant


stabilization


early-transition-metal


amide


complexes.


The


crystal


structure


Cp*2Hf(H)(NHMe)


(Cp*=


-C5Me5) reveals a Hf-N bond


distance


which


suggests


double


bond


character,


with


geometry


methylamido


group


exhibiting


planarity.22


Significant K-donation


may


restrict


free


rotation


about


M-N


bond


early-transition-metal


amide


complexes.


Recently,


Osborn


measured


barrier


rotation


W-N


bond


WO(CH


2But)3(NEt2), and


The


scarcity


found it to


late-transition-metal


18 kcal

1 amide


mol-


123


complexes


can


explained


similar


argument.


Late-transition-metals


cannot


accommodate


x -donation


from


amido


group.


The


LUMO


these


metals


either


too high


in energy


inaccessible


x -donation,


orbital s


with


proper


symmetry


accommodate


x-donation


are filled


with


d-electrons.


The


expected


geometry


amido


group


late-transition-metal


amide


complexes


trigonal


pyramidal


(B),
lack


with


localization


x -donation


electron-pair


late-transition-metal


on the


amido


complexes


group.
should


The


effectively


weaken


M-N


bond


compared


to early-transition-


metal


amide


complex


hence


late-transition-metal


amide


complex


should


exhibit


higher


reactivity


following


sections


trategies


preparing


late-


transition-metal


amide


complex


(groups


8-10)


will


discussed.


Due


nature


late-transition-metal


complexes,


different








complexes

compound


in organic


should


synthesis.


provide


The


a route


weak


M-N


bond


formation


new


group


carbon-


nitrogen


bonds.


Preparation


Late-Transition-Metal


Amide


Complexes


The


ynthesis


late-transition-metal


amide


complexes


gained


considerable


attention


over


five


years,


been


subject


extensive


reviews.


Although


there


are several


routes


preparation


class


compounds,


following


approach

reported i


are responsible


literature


to date:


majority


amide


transmetallation


complexes


ii)


deprotonation,


protonation,


N-H


oxidative


addition.


Each


these


routes


discussed


greater


detail


below.


Transmetallation.


was


discussed


previous


section,


transmetallation


reactions


most


common


route


to early-


transition-metal


the

the


majority

literature.


amide


complexes.


late-transition-metal


example


approach


amide


a transmetallation


also


complex


responsible


reported


reaction


seen


reaction


a Pt-N


bond


was


generated


Ph2
9p
P/
Pt

Ph2


LiN(Me)Ph


Ph2

p/
Ph2


SN(Me)Ph


flu LIVn








addition


amide


reagent


bis(phosphine)platinum(II)


alkyl


halide


complex.


The


amide


reagent


employed


transmetallation


reactions


controls


extent


M-N


bond


formation.


Although

complexes


amido


majority


are tolerant


group,


monomenc


a variety


preparation


early-transition-metal


alkyl


late-tran


silyl


ition-metal


groups
amide


amide


on the


complexes

success.26


using


these


Amide


amide


reagents


reagents


with


with


electron-withdrawing


limited


groups


such


as phenyl

formation.


groups


The


are the


nature


reagents


best


amide


suited


reagent


will


M-N


bond


discussed


greater


detail


following


chapter.


With


transmetallation


approach,


amide


complexes


29 Ni,


30a


Pd,30a,31


pt30a,31 a,32


have


recently


been


prepared


characterized.


Denrotonation.


The


preparation


M-N


bonds


deprotonation


involves


taking


advantage


increased


acidity


an aminme

center.33


proton
Once


when


an amine


amine


is coordinated


is coordinated


to a metal


a cationic


center,


metal


a base


then


added


to deprotonate


amine


generate


new


M-N


bond


1.3).


example


a deprotonation


reaction


involving


preparation


a late-transition-metal


amide


complex


can


seen


The


addition


bulky


base


KN(SiMe3)2


an amine


coordinated


cationic


metal


center


results


deprotonation


amine


proton


generate


new


Ir-N


bond.


1~4~34,35









KN(SiMe3)


Me3If


'CH3


(1.4)


Me3P'


Protonation.


Amines


are generally


not considered


acidic


substrates;


however


sence


a basic


substrate


then


amine


from


behave


metal


as a Bron


center


1.5).


acid


cleave


reaction,


basic


a group


substituent


bonded


metal


center


must


exhibit


significant


basicity


protonated


an amine.


One


such


example


seen


reaction,


M-OR


*


HNRR'


Ir(PPh)(H)(OEt)


M-NRR'


ROH


+ H2NPh


Ir(PPlh)(H)(NHPh)


EtOH


ethoxide


group


basic


substituent,


presence


aniline,


new


Ir-N


bond


was


generated


as well


as ethanol.36,37


The


preparation


reactivity


late-transition-metal


alkoxides


with


respect


protonation


received


considerable


attention.24a


The


basicity


ethoxide


group


attributed


localization


electron-pair


on oxygen.


Another


approach


can


found


in eq.


reaction


protonolysi


an alkyl


group


an acidic


amine


generates


new


NT~H








M-R


FH4RR'


M-NRR'


Et3P.


Et3P/


7Me


NMe


HNR


H2NR


Et3P~


PEt3


cH4,


NMe


(1.8)


= COCF3, COCF2H


complex.3 8,39


The


reaction


affords


a new


Pt-N


bond


evolution


methane


gas.


There


are two


possible


mechanisms


that


can


account


formation


new


M-N


bond


in eq.


The


first


mechanism


amide.


Indeed,


involves


protonolysi


cleavage


metal


M-C


alkyl


bond


group


acidic


palladium


platinum


complexes


with


protlc


reagents


been


documented.40


The


second


mechanism


involves


oxidative


addition


N-H


small


bond


alkane.


amine


Despite


followed


increase


reductive


number


elimination


late-


transition-metal


amide


complexes


generated


protonation


reactions


there


been


no evidence


to date


that


tinguishes


between


two


mechanisms.


One


factor


limits


utility


reaction


. 1.8


acidic


amines


are required


generate


new


M-N


bonds.


Indeed,


protonation


reactions


transition-metal


amide


involving


alkyl


complexes


hav


or silyl

e not


amines


been


generate


observed.


late-


Although


these


reactions


afford


new


M-N


bonds,


presence


PlPtrnn .i uth lra i/n an


otr~ni


Irrtllln*


amirdn


ntrtncren


malv


III illr


1


* I I








bond


late-transition-metal


amide


complexes


will


discussed


greater


detail


following


section


as well


as Chapter


N-H


oxidative


addition.


The


oxidative


addition


an N-H


bond


a metal


center


very


attractive


method


generating


M-N


bonds.


The


reaction


involves


addition


N-H


bond


metal


center,


which


increases


oxidation


state


metal


center


1.9).


date


iridium


systems41


exhibit


greatest


tendency

examples


N-H


toward


N-H


involving


oxidative


oxidative


other


addition


transition


can


addition;


metal


found


however


there


well.42


The


example


reaction


MLn


HNRR'


LnM


NRR
SNRR'


2 Ir(PEt3)2(C


H4)C1


2 NH3(1)


.10)


[Ir(PEt3)2(H)(NH3)(Q -NH2)]2(Cl)2


2 C2H4


involves


addition


N-H


bond


ammonia


to the


Ir(I)


metal


center,


generating


significance

developing


N-H


catalytic


Ir(III)


oxidative

systems


bridging

addition

which ir


amido s

reactions


corporate


pecies.41 a


The


possibility


N-H


oxidative


addition


as one


fundamental


steps


reaction.


Late-


Transition -Metal


Amide


Complexes


Catalysts


Amination


Olefins








with


net result


involving


functionalization


a carbon


center


1.11).


The


direct


addition


an amine


an alkene


absence


N-H


bond


olefins


a catalyst


an alkene


presence


is not a viable


however


a catalyst


approach

addition


with


addition


amines


some


to activated

success.43


NRR'


HNRR'


.11)


comprehensive


review


appeared


recently


discus


wide


variety


catalytic


systems


that


facilitate


addition


amines


to alkenes.44


olefins


using


trans


following

ition-metal


discussion


will


complexes


focus


on the


amination


catalysts.


One


approach


transition-metal


to the


complex


addition


amines


found


Figure


to olefins

re 1.3. C


employing

coordination


olefin


to the


metal


center


activates


toward


nucleophilic


attack.45,46


Attack


an amine


on the


coordinated


olefin


results


formation


a new C-N


bond


as well


as a new


M-C


bond.


The


first


example


type


reaction


was


reported


1969


, when


addition


a variety


amines


to cis-PtCl


2(olefin)PR3 generated


new


platinum-alkyl


complexes.47


Since


initial


report,


addition


amines


to coordinated


olefins


been


subject


considerable


interest.48


limiting


factor


to this


approach


a stable


metal-


alkyl


complex


produced,


thus


eliminating


-----J


possibility


_








electrophile,


or an oxidant


(Figure


1.3),


generating


functionalized


organic


M-


molecule.


E -NR3


M -NR3


IoD


Figure


Stoichiometric


addition


an amine


a coordinated


olefin.


Recently,


Trogler


reported


amination


activated


olefins


using


bis(phosphine)palladium


dialkyl


complex


catalysts.49


catalytic


cycle


these


amlnation


reactions


found


Figure


The


cycle


begins


with


protonation


an alkyl


group


on the


metal


center


ammonium


followed


coordination


neutral


amine.


The


complexes


Pd-amine

weak,50


interaction


amine


Pd(II)


bis(phosphine)


is displaced


an electron-


deficient


olefin.


The


coordinated


olefin


is now


susceptible


nucleophilic


attack


free


amine


palladium-alkyl


complex


is generated.


Protonolysis


alkyl


group


with


ammonium


affords


new


ammonium


as well


as the


active


catalytic


species
... I = -.


Although


system


is quite


effective


limited


"a-'-. -A.- a- -. I. n n n n mini a ow :~. ~- 1 n n a I ,~: n a rw


1


,1, e,


D X


nnn


n












Pd
\p


2
NRR'R""

D

HNRR'R""


Pd
\Pe


+ HNRR'R""
-RH

R1


NRR'R""


Pd

C R2


+
*NRR'R"


Pd
/A


NRR'R""


Figure


Catalytic


cycle


nucleophilic


formation


attack


decomposition


amination
an amine


products


an olefin


on a coordinated


recovery


olefin.


unreacted


olefin.


Another


approach


to the


amination


olefins


seen


Figure


i) N-H


This


oxidative


catalytic


addition


cycle

to the


consists


metal


center,


following


three


steps:


insertion


I,


r








limited


number


examples


involving


oxidative


addition


N-H


bonds


transition-metal


centers.41


little


known


about


mechanism


catalytic


cycle


Figure


. This


approach,


however,


does


take


advantage


relatively


weak


M-N


bond


late-transition-metal


amide


complexes.


Bryndza


Bercaw


have


experimentally


demonstrated


Ru-N


Pt-N


bond


Cp*(PMe3 )2RuNPh2


(DPPE)MePtN(Me)Ph


(DPPE=


bis(diphenylphosphino)ethane


order


kcal-mol
bonds.37


respectively


The


weaker


insertion


than


olefins


similar


Ru-C


acetylenes


into


Pt-C


metal-carbon


bond


been


observed


variety


late-transition


metal


complex


therefore


insertion


these


unsaturated


substrates


into


M-N


bond


might


facile.


The


reactivity


late-transition-


metal


amide


complexes


with


unsaturated


organic


molecules


will


discussed


greater


detail


Chapter


date,


hydroamination


there


only


an olefin


that


example

involve


catalytic


N-H


oxidative


addition.


Casalnuov o


et al.


have


successfully


added


N-H


bond


aniline


across


carbon-carbon


bond


norbornene


, generating


exo-


(phenylamino)norbornane


(eq.


Their


approach


to the


design


HNPh


Ir(PEt3) 2(C 2H4 C


PhH


7MG


.12)


2).5














H
1 2R


ML,


S/H
LnM
I 2NR


C2H4


Figure


Catalytic


cycle


amination


an olefin


N-H


oxidative


addition


a transition-metal.


HNR 2


/H








amido


anilide


complex
hydride


revealed


moieties.


stereochemistry


When


with


Ir(PEt3)2(C2H4)CI


respect


was


refluxed


presence


aniline


excess


norbornene,


insertion


product


was


isolated


.13).


Reductive


elimination


was


observed


thermolysis


at 80


presence


trapping


ligands,


or at


room


temperature


presence


a catalytic


amount


of ZnCl2 (eq.


1.14).


+ H2NPh


Et3P


Ir(PEt3)2(C2H4)CI


Ir


.13)


Et3Pt


I /NHPh
I NHPh


Et3P


Zn Cl2


""Ir "*


.14)


Et3P~


CTHF


I NHPh
a3


defining


each


catalytic


cycle


Figure


, a catalytic


process
addition


was


developed


aniline


to norbornene


hydroamination


norbornene.


The


presence


equivalent


ZnCl


refluxing


THF


hours


results


slow


formation


to 6


turnovers).


a control


experiment,


formation


observed


when


aniline


was


added


norbornylene


absence


iridium


catalyst








InvPctih ti tnn


Palladium(II)


, *Al a.l V Jy -Cm L.a all nyIn - -- --


Amide


Complexes


Our


research


interests


have


focused


preparation


monomeric


palladium(II)


amide


complexes.


While


number


late-transition-metal


limited


number


amide


complexes


palladium(II)


amide


increasing,

complexes


there


that


have


only


been


characterized.


The


first


isolated


characterized


palladium(II)


amide


complex


was


reported


Fryzuk


1982.31a


The


synthesis


involves


addition


an anionic


tridentate


ligand


to Pd(PhCN)2C12


1.15).


The


reaction


takes


advantage


coordination


"soft"


phosphine


ligands


palladium


metal


center.


While


compound


fairly


stable,


limited


reaction


chemistry


with


respect


to the


Pd-N


bond.31a,b


Trogler


recently


reported


synthesis


hydrido


preparation


these


amido


complex


complexes


also


palladium(II).30a


involves


The


transmetallation


reactions


.16).


Unlike


chelate


stabilized


amide


complex


reported


Fryzuk,


amide


complex


thermally


unstable


room


temperature,


decomposes


form


aniline


Pd(PCy3)2.


1


Pd(PhCN)2C12


+ LiN(SiMe2CH2Ph2)2


N-


PPh2
\-

-Pd


PPh2


__a1


.15)








PCy3


;rans-PdHCl(PCy3)2


NaNHPh


Pd -NHPh


.16)


PCy3


lack


stable


palladium(II)


amide


complexes


warranted


thorough


convenient


investigation


method


into


class


synthesi


compounds. I

palladium(II)


Chapter


amide


complexes


will


discussed.


The


emphasis


chapter


characterization


monomernc


dimeric


amide


complexes,


with


a detailed


discussion


their


structure


bonding.


findings


bond


group.


Chapter

prompted

Chapter ,


provided


better


us to investigate


reactivity


understanding


reactivity


Pd-N


bond


Pd-N


amido


with


unsaturated


organic


molecule


discussed.


outlined


Figure


insertion


unsaturated


ubstrate


into


M-N


bond


generated


a new


carbon-nitrogen


bond.


The


potential


palladium(II)

the emphasis


molecules


with


amide


Pd-N


complexes


chapter.

multiple


facilitate


Chapter


bonds


carbon-nitrogen


, attempts


referred


will


to prepare


as imido


complexes,


presented.


The


potential


these


compounds


to behave


nitrogen-transfer


reagents


will


focus


chapter.













CHAPTER


EXPERIMENTAL


General


Considerations


procedures


were


carried


under


atmosphere


argon,


using


either


Schlenk


or drybox


techniques.


Diethyl


ether,


pentane,


hexane


were


distilled


from


sodium/benzophenone.


Toluene


tetrahydrofuran


Methylene


were


chloride


dried


was


refluxing


distilled


over


over


P205.


potassium
Deuterated


metal.


solvents


were


dried


over


molecular


sieves,


degassed


using


freeze-thaw


techniques.


NMR


spectra


were


obtained


on either


General-Electric


QE-300


Varian


VXR-300


spectrometers.


Proton


or carbon


chemical


hifts


were


referenced


to residual


signals


solvent


are reported


relative


to TMS


31p


chemical


hifts


reported


relative
external


to external
CC13F in


85%

C6D6


H3P04. 19F
Infared data


chemic;
were


shifts


obtained


were
using


reported t

a Perkin-


Elmer


1600


spectrometer.


Elemental


analyses


were


performed


Atlantic


Microlabs,


or the


analytical


services


department.


Mass


spectroscopy


data


were


obtained


with


a Finnigan


4500


Chromatograph/


Mass


Spectrometer.


The


following


compounds


were


purchased


from


Aldrich


Chemical


used


directly


without


further


purification:








butyl


isocyanate,


2,6-diisopropyl


isocyanate,


4-iodoanisole,


iodoaniline,


1,2,3,4,5-pentafluoroaniline,


3,5-bis(trifluoromethyl)aniline,


PCy3,


PdC12,


and Pd(OAc)2.


Aniline


and N-methylaniline
Trimethylphosphine


were


was


distilled


prepared


from


sodium


addition


metal.


CH3MgI


P(OPh)3


n-butyl


ether.


Diphenyl


ketene


was


prepared


using


literature


procedures.5 4


potassium


amides


were


prepared


reaction


between


corresponding


aniline


THFf,


with


KN(Me)Ph


prepared


modified


literature


procedures.55


The


compounds


trans-


(PMe3)2Pd(Ph)I


(14)56


, trans-(PMe3)2Pd[CH=C(H)C6H5]Br (21)57


and trans-(PMe3)2Pd(CH3)I


(22)58


were


prepared


literature


procedures.


The


compounds


trans-(PMe3)2Pd(p-OCH3


-C6H4)I


(16)


trans-(PMe3)2Pd(o-NH2-C6H4)I


(17)


were


prepared


addition


Pd(PMe3)4:


4-iodoanisole
59 in pentane.


and
The


2-iodoaniline
Compound 4


to a solution


cis-Pd(PMe3)2(CH3)2 was


prepared


addition


excess


MeLi


a diethyl


ether


solution


of trans-Pd(PMe3)C12.60


compound


trans-Pd(PMe3)212 was


prepared


using


literature


procedures61


The


compound


trans-


Pd(PCy3)212


was


prepared


addition


equivalents


PCy3


to a solution


trans-Pd(PhCN)212


diethyl


ether.


compounds


[(C6H4CH=NR)PdC1]262 and


[(C6H4CH=NR)Pd(NCCH3)2 [BF4163


literature


procedures.


The


compound


(R=Ph, Pr') were prepared by

[(C6H4CH=NR)PdI]2 was








pri; 13,


= Ph)


were


prepared


addition


excess


PMe3


[(C6H4CH=NR)PdI]2 in CH2C12.


Synthesis


Characterization


Preparation


QL TCf; a4 C ~ r=N Pr' P d(P Me ? 3 jL EEd1 4L4


To a solution of [C6H4CH=NPrl)Pd(CH3CN)2][BF4] (4.90 g,


12.18


mmol)


CH2C12


was


added


three


equivalents


of PMe3


(26.68


36.54


mmol;


1.32


toluene),


suspension


was


stirred


hour.


Solvent


was


removed


under


reduced


pressure,


6.32 g


was


isolated;


yield


91.4%.


Recrystallization


from


dichloromethane/diethyl


suitable


solution


X-ray


with


diethyl


ether


diffraction


ether.


gave


was


Anal.


yellow


grown
Calcd.


crystals.
layering


single


crystal


a CH2C12


for C19H39BF4NP3Pd:


40.20; H,


6.88; N, 2.47.


Found:


39.91


6.97


N, 2.31.


Preparation


QLLf6I4Ct~IC(H')=NPh')d(P1Me331LU.E4 1(5


To a solution of [C6H4CH=NPh)Pd(CH3CN)2][BF4] (4.54 g,


10.00


mmol)


CH2C12


was


added


three


equivalents


PMe3


(30.96


30.96


mmol;


PMe3


toluene),


suspension


was


stirred


one


hour.


Solvent


was


removed


under


reduced


pressure,


was


isolated


as an off-white


powder;


yield


95%.


Anal.


Calcd. for C22H37BF4NP3Pd: C,


43.91; H, 6.15; N, 2.33.


Found: C,


43.82;


6.29;


2.20.








Preparation


trans-(PMe3 2Pd ( C 6H4C(H)=NPr)(NHPh)


solution


4 (2.00


3.53


mmol)


of THF


was cooled


-60C.


solution


was


added


KNHPh


(472.4


3.60


mmol)


as a solution


warmed


room


THF.


Once


temperature


amide


stirred


added,


hours.


mixture


The


was


solution


was


a deep


orange-red


with


very


fine


suspended


solid.


The


solvent


was


removed


under


reduced


pressure,


residue


was


extracted


with


diethyl


ether


(4x50


extract


was


concentrated


approximately


cooled


to 0 C.


After


recrystallizations,


bright
Anal.


yellow


Calcd.


crystals


were


for C22H35N2P2Pd: C,


isolated


50.06


(698


mg);


6.87


yield
5.31.


37.5%.


Found: C,


49.93; H,


7.01


N, 5.29.


Addition


CH3I to trans-(PMe3)2Pd(6H4C(H)=NPri NHPh)


drybox,


a solution


trans-


(PMe3)2Pd(C6H4C(H)=NPri)(NHPh)


(9) (20 mg,


0.04 mmol) in 0.5


of C6D6


After


was


hours


prepared.


room


solution,


temperature,


excess


was


CH3I


completely


was added


converted


trans-(PMe3)2Pd(C6H4C(H)=NPrl)I (41)


Preparation


N-methylaniline.


trans-(PMe3).2Pd(C6H4C(H)=NPh)(NHPh) (10)


A solution of [C6H4C(H)=NPh)Pd(PMe3)3][BF4] (1.00 g,


1.66


mmol) in 30 ml


of THF


was cooled


to -78


solution


was


added KNHPh


(240 mg,


1.83


mmol)


as a solution


THFf.


Once








diethyl


ether


x 50


ml).


The


combined


extracts


were


filtered,


concentrated


to ca.


cooled


to 0 C.


After


recrystallizations,


bright


yellow


crystal


were


isolated


(557


mg),


yield 63.3%.


(nujol)


1615 cm-1 (uC


=N).


Anal.


Calc. for


C26H36N2P2Pd: C, 56.56; H, 6.41


N, 5.28.


Found: C, 56.31


H, 6.50; N,


5.19.


Preparation


trans-(PMe32 Pd(Ph)(NHPh) (15)


solution


trans-(PMe3 )2Pd(Ph)I


(278


0.60


mmol)


of THF


was cooled


to -78


this solution


added


KNHPh


(118


0.90 mmol)


as a solution


THF.


Once


anilide


was


added,

stirred


reaction


hours.


mixture


was


Solvent


warmed


was


removed


room

under


temperature


reduced


pressure,


remaining


residue


was


extracted


with


diethyl


ether


(2x15mi).


The


orange


extracts


were


filtered,


concentrated


cooled


filtration


diffraction


3327


to 0


0 C


studies


cm-1 (uN-H).


(135


was


Anal.


Yellow


mg);


grown


yield


crystals

52.6%.


from


diethyl


were


crystal


ether


Calc. for C18H29NP2Pd


then


suitable


at 0


C, 50.54


isolated


X-ray


(nujol):
6.79; N,


3.28.


Found:


49.81


6.90


N, 3.20.


Preparation


trans-(PMe3).2Pd(Ph)(liNHPh)


The


1 N-labelled


compound


trans-(PMe3)2Pd(Ph)('5NHPh)


(15-15N)


was


synthesized


following


same


procedure


using


4








Preparation


trans-(P Me32Pd (C6H4-pOCH )(NHPh)


(18.~


A solution of


trans-(PMe3)2Pd(C6H4-pOCH3)I


(261


0.57


mmol) was dissolved


in 20 ml


of THF


cooled


to 0 C.


solution


was


added


KNHPh


(112


0.86


mmol)


as a solution


THF.


The


solution


was


allowed


warm


room


temperature


hours,


at which


time


solution


changed


to bright


yellow.


Solvent


was

was


removed

extracted


under

with


reduced


diethyl


ssure,


ether


ml).


The


remaining


extract


residue


was


concentrated


cooled


to 0 "C.


Recrystallization


afforded


as yellow


crystals


yield


31.0%.


Anal.


Calcd.


C19H31NOP2Pd: C,


49.85


H, 6.78; N, 3.06.


Found


49.69; H, 6.87


3.02.


Preparation


trans-(PMe f2Pd(o-NH2-C6H4 (NHPh)


(~Li)


solution


trans-(PMe3)2Pd(o-NH2-C6H4)I


(652


1.37


mmol)


was dissolved


in 20 ml


of THF


cooled


to -78


To this


solution


was


added


KNHPh


(215


1.64


mmol)


as a solution


THfF.


Once


amide


was


added


solution


was


warmed


room


temperature


stirred


hours.


The


solution


color


was


green-


yellow

under


with


a fine


reduced


suspended


ssure


precipitate.


remaining


Solvent


residue


was


was


removed


extracted


with


diethyl


ether


x 20


ml).


yellow


filtrate


was


concentrated


to ca.


cooled


to 0 C,


affording


of 19


as yellow


crystal


yield


61.3%.


(nujol,


3295,


3339,


3374,


3409


(VN-


cm-l):








Preparation


trans-(PMe3 PdrCH=C(H) C6H5 1(NHPh)


(21)


In a Schlenk tube, trans-(PMe3)2Pd[CH=C(H)C6H5]Br


(647


mg,1.47

C and


warmed


mmol)


dissolved


room


KNHPh


in 20 ml


(231


cold


temperature,


1.76


(-60 C)


which


mmol)


THF.


time


were


cooled


to -60


The solution


formation


a fine


precipitate


was


observed


After


stirring


hours


room


temperature,


removal


solvent


under


reduced


pressure


followed


extraction


solution.


with


The


diethyl

solution


ether


was


concentrated


afforded


to ca.


a deep


orange


cooled


to 0


affording


as bright


yellow


crystals


(145


mg);


yield


28.3%.


(nujol)


3342 cm-1 ('N-H),


1580 cm-1 (oC=C).


Anal.


Calc.


C20H31NP2


Pd: C, 52.93; N, 6.84; N, 3.09.


Found: C,


52.68; H, 6.93; N,


3.01.


Preparation


trans-(PMe 2Pd(CH )(NHPh)


(23)


Schlenk


tube


was


charged


with


trans-(PMe3)2Pd(CH3)I


(500


1.25


mmol)


KNHPh


(149


1.14


mmol).


The


solids


were


then


dissolved


THF


room


temperature,


at which


time


solution


color


became


pale


yellow


with


formation


a fine


white


precipitate.


solvent


was


After


removed


stirring


under


reduced


hours


pressure,


room


temperature,


remaining


residue


was


extracted


with


diethyl


ether.


The


orange-


yellow

0 oC,


solution


affording


was


yellow


filtered


crystals


concentrated


of 23


mg);


yield


19.3%.


cooled


Due








Calcd.


for C13H27NP2Pd: C,


42.69; H,


7.39; N, 3.83.


Found: C,


41.71; H,


7.26;


3.71.


Addition


Aniline


to cis-Pd(PMe3 ).2(CH312


the drybox,


cis-Pd(PMe3)2(CH3)2


0.12


mmol)


was


dissolved


C6D6.


solution


added


one


equivalent


aniline


The


solution


was


then


sealed


an NMR


tube


fitted


with


Youngs


teflon


valve.


The


sample


was


placed


temperature
monitored


controlled


NMR


bath,


progress


reaction


was


spectroscopy.


Preparation


trans-(PMet)2Pd(Ph)FN(Me)Phl (26)


solution


trans-(PMe3 )2Pd(Ph)I


(450


1.05


mmol)


was


dissolved in


20 ml


of THF


and cooled


to 0


this solution


was


added


KN(Me)Ph


(229


1.58


mmol)


as a solution


THF.


The


solution


was


allowed


warm


room


temperature


was


stirred


hours.


The


solution


color


was


orange-yellow,


a fine


solid


was


present.


extraction


Removal


with


diethyl


solvent


under


ether


reduced


afforded


pressure
a yellow


followed


solution.


The


solution


was


filtered,


concentrated


cooled


at which


time


yellow


crystals


developed


(147


mg)


yield 31.6%.


Anal.


Calc. for C19H31NP2Pd: C, 51.65


7.02; N, 3.17.


Found: C, 51.71


7.11


N, 3.16.








added


KNPh2


(184


0.89 mmol)


as a solution


THF.


The


solution


was


then


allowed


warm


room


temperature


hours.


Solvent


was


removed


under


reduced


pressure,


remaining


residue


was


extracted


with


diethyl


ether


ml).


The


yellow


solution


filtered


concentrated


Recrystallization


from


diethyl


ether


at 0


afforded


as yellow


crystal


(118


mg)


yield 39.7%.


Anal.


Calc.


for C24H33NP2Pd


57.21; H,


6.56; N, 2.78.


Found


57.11


6.54; N, 2.75.


Preparation


t ra nse(P M et12Pd( P h )(N H -2 .6e-iPr9C.6UH3 L 2h.


solution


trans-(PMe3 )2Pd(Ph)I


(316


0.69


mmol)


was


dissolved


2,6-ipr2-C6H3


of THF


(223


C).


1.04 mmol)


solution


as a solution


THF


added


KNH-


at room


temperature.


The


solution


allowed


to stir


hours.


The


yellow


pressure.


solution


The


ml),


was


filtered,


yellow-brown


filtrate


cooled


solvent


was


to 0


removed


extracted


After


with


several


under


diethyl


days


reduced


ether


at 0


yellow
(nujol):


crystals


3385


were


cm-1 (ON-H).


collected


Anal.


Calc.


(110


mg);


yield


for C24H41NP2Pd


31.2%.


C, 56.32; H,


8.02; N,


Found: C, 55.21;


8.08; N,


2.53.


Preparation


trans-(PMe) 2Pd(PhW(NHPh-pCH) (292)


solution


trans-(PMe3 )2Pd(Ph)I


(479


1.12


mmol)


was


dissolved


20 ml


of THF


cooled


to 0


solution


was


H,








finely


suspended


solid.


Solvent


was


removed


under


reduced


pressure,


remaining


residue


was


extracted


with


diethyl


ether


ml).


Recrystallization


at 0 C


afforded


of 29


as yellow


crystals;


yield 31.1%.


(nujol,


cm-1): 3333


(UvN-H).


Anal.


Calcd. for


C19H31NP2Pd: C, 51.65; H,


7.02; N, 3.17


. Found: C,


49.31


7.07


2.80.


Preparation


trans -( PMef l2EPdf.C.i4 C (Hl) =N Ph) (Nll P h -pDCHI3fl (


A solution of [(C6H4C(H)=NPH)Pd(PMe3)3][BF4] (900 mg,


1.50


mmol)


was dissolved in


of THF


cooled


to -78


solution


THF.


warmed

removed


was


added


Once


room


under


KNHPh-pCH3


amide


temperature


reduced


was

and


pressure,


(218


1.50


added,

stirred


mmol)


reaction


as a solution


mixture


hours.


remaining


was


Solvent


residue


was


was


extracted


with


diethyl


ether


(3x50


ml).


The


solution


was


filtered,


solvent


was


removed


reduced


pressure.


The


remaining


residue


was


extracted


with


pentane


(3x30


ml).


Upon


recrystallization


crystaline


solid


from


(254


pentane


mg);


yield


at 0


31.1%.


was


isolated


(nujol)


1605


as a yellow
cm-1 (uC=N).


Anal.


Calc. for C26H36N2P2Pd: C,


57.31


H, 6.61


N, 5.14.


Found: C,


57.06;


6.69;


N, 5.03.


Preparation


trans-(PMe.2Pd(C6H14 C(H)=NPh )(NC4kH4 (31)


A solution of [C6H4C(H)=NPr1)Pd(PMe3)3][BF4] (220 mg, 0.37








warm


removed


room


under


temperature


reduced


pressure,


four


hours.


remaining


Solvent


residue


was


was


extracted


with


diethyl


ether


ml).


bright


yellow


solution


was


filtered


concentrated


Recrystallization


at 0


afforded


bright


yellow


crystals


mg);


yield


45.5%.


Anal.


Calcd.


for C23H32N2P2Pd: C,


54.7


H, 6.34; N, 5.56.


Found


C, 52.53;


H, 6.10; N, 5.31.


Preparation


I(PMe3)Pd(Ph)(u


-NHPh)12 (32)


a Schlenk,


mtorr


(117


at which


0.27


time


mmol)


was


yellow


warmed


solid


was


to 900


converted


grey
ether


powder.

at 0 C


Recrystallization


afforded


white


grey


powder


microcrystals


from


mg),


diethyl


yield


33.4%.


from diethyl


crystal
ether.


suitable


(KBr):


X-ray


diffraction


3292 cm-1 (uN-H).


tudie


Anal.


was


grown


Calc.


C30H40N2P2Pd2


C, 51.22; H, 5.69


N, 3.98.


Found: C, 51.23


H, 5.72;


N, 3.95.


Preparation


r(PMe Pd(C H-)(u-NHPh)1? (34)


a Schlenk


tube,


(174


0.48


mmol)


was


warmed


to 70


under


reduced


pressure


(200


mtorr)


hours,


which


time


yellow


solid


converted


a white


powder


(111


mg);


yield


80.6%.


NMR


revealed


complete


conversion


to the dimer 34.


Recrystallization


from


diethyl


ether


at 0


afforded


crystals








Addition


PMe3


to Compounds


and 34


drybox,


approximately


dimer


was


dissolved


of C6D6


an NMR


tube


was


fitted


with


a Youngs


teflon


valve.


solution


was


added


three


to four


equivalents


PMe3


as a solution


C6D6.


The


conversion


and 34


to 15


and 23


respectively


was


monitored


NMR


spectroscopy.


Preparation


LPMeaXLC frIL H4C H =NP rlI


(31}


solution


[Pd(C6H4CH=NPrl)I] 2


(195


0.257


mmol)


was


dissolved


CH2C12


room


temperature.


solution,


PMe3


was


added


(0.515


mmol;


0.78


0.66


PMe3


TIfF).


Upon


addition


PMe3,


solution


color


changed


from


orange


yellow.


After


stirring


minutes


at room


temperature,


solvent


was


removed


under


reduced


pressure,


affording


as an


orange


solid;


yield


100%.


Preparation


(fPMe )Pd(C H4_CH=NPrl)(W-NHPh)


(36)


a Schlenk


tube,


9 (15


mg)


was


warmed


to 85


under


reduced


(400


mtorr).


After


hours,


yellow


solid


was


converted


to a brown oil.


1H NMR


spectrum


C6D6


revealed


was


completely


converted


dimeric


amide


complex


with


no indication


formation


Compound


(135


0.30


mmol)


was


dissolved


of THF


room


temperature.


solution,


KNHPh


0.357








under


reduced


pressure.


The


orange


residue


was


extracted


with


diethyl


ether.


The


extract


was


filtered


concentrated


After


several


at 0 C,


orange


microcrystals


were


isolated


mg).


The 31p(1H})


NMR


spectrum


C6D6


was


consistent


with


the 31P


NMR


spectrum


Thermolysis


Studies


The

performed
dissolving


thermolysis


identical


15-20


compounds

procedure.


amide


complex


,23, 32, 34


typical


and 36


experiment


were


involved


C6D6 or d8


toluene


an NMR


tube


fitted


with


Youngs


teflon.


The


NMR


tube


placed


thermowatch.


an oil


The


bath


reaction


with


was


temperature


monitored


controlled


NMR


an 12R


spectroscopy.


prenarationn


cis-(PMe 32Pd(CH )(NHPh)


(38)


A solution


trans-(PMe3 )2Pd(CH3 )I


(1.036


2.59


mmol)


THF


was cooled


toO


this solution


was


added


KNHPh


(407


3.10


mmol)


as a solution


THF


C).


Upon


addition


amide


reagent,


solution


color


changed


from


bright


yellow


to off-


white.


The


solution


was


allowed


to stir


minutes


at 0


which


time


a fine


precipitate


formed.


Solvent


was


removed


under


reduced


pressure,


remaining


orange-brown


residue


was


extracted


with


diethyl


ether


2x10


ml).


The


extracts


were


collected


filtration,


solvent


was


removed


under


reduced








Recrystallization


from


diethyl


ether


affords


off-white


crystals,


contaminated


small


amounts


as detected


NMR


spectroscopy
Preparation o


[(PMe3 )Pd(CHIIIU,


-C HP Me)1..2 (40)


a Schlenk


tube,


trans-(PMe3)2Pd(CH3)21


(215


0.54


mmol)


LiCH2PMe2


0.53


mmol)


were cooled


The


solids


were


dissolved


cold


(-78


THF


The


solution


was


allowed


warm


to 0 C,


at which


time


a fine


white


precipitate


formed.


After


solution


was


tirred


minutes,


solvent


was


removed


under


reduced


pressure.


The


gray


was


washed


with


cold


diethyl


ether,


was


converted


white


solid


mg);


yield


28.1


suitable


X-ray


diffraction


studied


were


recrystallized


from


diethyl


ether.


PreDaration


trans-(PMetL2Pd(Ph)[OC(O)NHPhl (42)


Carbon


dioxide


was


trans-(PMe3 )2Pd(Ph)(NHPh)


bubbled


(139


into


0.33


a pale
mmol)


yellow


solution


pentane


five


minutes.


During


time,


a white-yellow


precipitate


formed.


The


solution


was


allowed


to stir


hours


room


temperature


under


a C02


atmosphere.


Solvent


was


removed


under


reduced


pressure


to afford


yield


81.6%.


Recrystallization


from


diethyl


ether


at 0 C


afforded


white


crystals

(oc=o).


suitable


analysis.


Anal. Calcd. for Cl9H


(KBr,


29N02P2


cm-1)


3286


48.37


H, 6.15; N


1630


2.97.


(Z)N-H)r








Preparation of


trans-(PMe()2Pd(Ph)rOC(O)C(H)=C(H)C(O)NHPh1 (43)


To a solution


trans-(PMe3 )2Pd(Ph)(NHPh)


0.20


mmol)


pentane


was


added


maleic


anhydride


0.22


mmol).


The


solution


was


allowed


to stir for


hours


at room


temperature,


during


which


time


white


precipitate


formed.


The


white


precipitate


was


isolated


filtration


washed


with


pentane


give


crude


product


(43);


yield


69.5%.


Recrystallization


from


diethyl


ether


at 0 C


produced


white


microcrystals


suitable


analysis.


(KBr,


cm-1)


2731


(UN-H),


1670


(vc=o),


1621


(vc=o), 1589 (uc=c).


Anal. Calcd.


for C22H31NO3P2Pd


50.24; H, 5.90; N, 2.66.


Found: C


50.01


H, 5.89


2.64.


Preparation


transa(P M~e_7 )Pd(P h) rN(Ph)C(O)~C(W)P h91I 45


Excess


diphenyl


ketene


trans-(PMe3)2Pd(Ph)(NHPh)


was


(0.2
(136


0.32


added


a solution


mmol)


pentane.
observed.


Immediate


The


solution


formation


was


allowed


a pale


to stir


yellow


precipitate


hours


was


at room


temperature.


The


precipitate


was


isolated


filtration


give


crude


product


(45);


yield


68.3%.


(KBr,


cm-1):


1598 (uc=o).


HRMS (CI) Calcd.


for C32H39NOP2Pd


621.1666 (M+1).


Found:


.1620


Preparation


(M+1).


trans-(PMe3 )2Pd(Ph)[N(Ph)C(O)NH(t-B u)1 (47)


To a solution


trans-(PMe3)2Pd(Ph)(NHPh)


(103


0.22








3334 (UN-H),


1616 (uc=o).


HRMS (CI) Calcd. for C23H38N20P2Pd:


526.1493


(M+1).


Found


526.1509


(M+1).


Preparation
C6H31(481


trans-(PMe3 )Pd(Ph) N(Ph)C(O)NH-2.6 -Pr-l


To a solution of


mmol)


trans


pentane


-(PMe3)2


was


Pd(Ph)(NHPh)


added


0.22


2,6-diisopropylphenyl


isocyanate


0.33


mmol).


white


precipitate


formed


upon


tirnng


hours.


Isolation


white


solid


filtration


afforded


yield


67.7%.


(KBr


3337


1619


(ulcg4o


Preparation


trans-(PMet)2Pd(Ph)[N(Ph)C(O)NHPh1 (49)


Phenyl


isocyanate


0.20


mmol)


was


added


a solution


trans-(PMe3)


2Pd(Ph)(NHPh)


0.20


mmol)


pentane.

Isolation

45.5%.


white


precipitate


white


IR (KBr, cm-


formed


filtration


3318 (UN-H),


1627


upon


stirring


afforded

(uc=o).


hours.


yield


HRMS (CI) Calcd. for


C25H34N20P2Pd


546.1180


(M+1).


Found


546.1203


(M+1).


Preparation


1IN-Labelled


Compounds


Following


same


procedure


was


reacted


with


maleic


anhydride,


diphenyl


ketene


t-butyl


isocyanate


generate


respectively


an NMR


tube


a solution


w~ -r w


w .


0.05


mmol)


U


(Z)N-H)r


15N


--


.


v --








reaction


was


monitored


NMR


spectroscopy


at 200


integrals


between


temperature


range


to 20


an NMR


tube,


a solution


of 15-15N


0.04


mmol)


dg-toluene


was


prepared


cooled


to -78


solution,


one


equivalent


t-butyl


isocyanate


was


added


(4.5


pl).


The


reaction


was


monitored


NMR


spectroscopy


at 200


integrals


between


temperature


range


to 20


an NMR


tube,


a solution


of 15-15N


0.06


mmol)


dg-toluene


was


prepared


cooled


to -78


solution,


one


equivalent


phenyl


isocyanate


was


added


The


reaction


was


monitored


NMR


spectroscopy


at 200


integrals


between


temperature


range


to 20


Pem a a ao


of trans-(PMe2_PdI(MeOOC)IC=C(COOMe )(NHPh)1(Ph )(50)


a solution


(103


0.24


mmol)


pentane


room


temperature


was


added


dimethylacetylene


dicarboxylate


(DMAD)


0.72


mmol).


Upon addition


of DMAD


an off-white


precipitate


formed.


The


solution


was


tirred


hours


room


temperature.


Isolation


precipitate


afforded


insertion


product


yield 40.2%.


(KBr, cm-1)


1702


1686


(vc=o),


1600 (uc=c).


Anal. Calcd. for C24H35NO4P2Pd: C, 50.58; H, 6.15


2.46.


Found: C, 50.33; H,


6.18;


Preparation of trans-
(PMe3 )Pd (MeOOC)C=C(COOMe NHPh (C64C(H)=NPh) (51)








precipitate


formed.


The


solution


was


stirred


hours


room


temperature.


Isolation


precipitate


afforded


insertion


product


(170 mg);


74.8%.


(nujol,


cm-1):


1714


1671


(UC=o),


1615


(uc=c).


Anal. Calcd. for C31H40N204P2Pd:


C, 55.47


H, 5.96; N,


4.18.


Found


C, 55.28; H,


6.05; N,


4.06.


Preparation


SAL-+


iL1-N


With


a procedure


identical


to that


a solution


trans-


(PMe3)2Pd(Ph)(15NHPh)


pentane


was


reacted


with


DMAD.


NMR


(CDC13): 85.96 ppm (d, JN-H=85 Hz,


N-H,


1H).


With


a procedure


identical


to that


a solution


trans-


(PMe3)2Pd(C6H4C(H)=NPh)(15NHPh)


in pentane


was


reacted


with


DMAD.


1H NMR (CDC13): 85.76 ppm (d,


1JN-H=84 Hz,


15N-H, 1H), 85.89


ppm (d,


1JN-H=84 Hz,


Maonetization


Transfer


1H).


Experiment


-r~k~ v~ W* e w -) --- -Y -~ -- -- -


magnetization


transfer


experiments


were


performed


Varian


VXR-300


spectrometer.


perform


a magnetization


transfer


experiment,


obtain


NMR


spectrum


sample


a selected


temperature


experiment


one.


Move


parameters


experiment


join


one


experiment


to experiment


four,


type


four


JEXP4.


typing

Once i


command


experiment


MP(1,4).


four,


type


command


SEQFIL(SATDIF).


This


command


will


setup


experiment


order


perform


magnetization


transfer


-~~ ~ ~ ~ -~r A- --- n -a a


ni-a--.


.:,,


-n *" K.s


*


t^ V\a


IsN-]H,


ct. A


,, L


*








value


imine


signal


at 8.63


ppm


was


1360.2.


The


command


parameters


experiment


Replace


existing


value


with


value


that


was


obtained


above.


order


(decoupler


to irradiate


power)


a particular


to be


ignal,


adjusted.


value


trial


DLP


error,


different


values


DLP.


lower the


value


DLP,


greater


decoupling


power.


After


setting


value


DLP


a quick


experiment


(NT


= 4)


typing


GA,


see if


selected


signal


inverted.


Remember,


observed


spectrum


a difference


spectrum,


with


therefore


inverted


find


signal


value


only;


DLP


no other


signals


results


should


with


a spectrum


present.


DLP


was


compound


at 45


Once


difference


spectrum


been


obtained,


delay


intervals


must


established.


The


value


represents


relaxation


times


were


never


period

value c


between


measured


experiments,


particular

a value


signal.


should


Although


seconds


at least


was


five


values


utilized


Once


signal


been


inverted


a 180


pulse,


system


allowed


to equilibrate


over


a certain


time


form


magnetization


transfer


before


inverted


ignal


irradiated


with


second


pulse.


These


delay


times


(represented


Chapter


also


obtained


trial


error.


parameters,


change


value


perform


magnetization


transfer


experiment


typing


GAIN=Y


followed


GA.


Once


a time


range


been








compound


was


D2(1)=0,0.1,0.2


...2.0.


With


array


of D2


values


place,


experiment


spectra.


magnetization


complete,


display


experiment
command


spectrum


performed.


DSSA


a particular


display


value,


After


stacked


type


where # is


#=2,


number


The command


experiment


PL(ALL)


will


(i.e.


at D2=0,


stacked


D2=0.1,


spectra.


typing
stacked


command


spectra


APH,


in Figure


inverted


order


spectra


to use


will


appear


. 4.13,


as the


press


command


to obtain


integrals


from


each


spectrum.


Preparation


trans-(PMet)2Pd(o-NH2-C6H41


(CHTj3OCC= C(CO9CH)NHPh) (52)


solution


trans-(PMe3)


2Pd(o


-NH2


-C6H4)(NHPh)


(213


0.48


mmol)


was


dissolved


diethyl


ether.


solution


was added DMAD (


0.53


mmol


0.47


of 1


M ii


THF) at 25


Upon


addition


DMAD,


solution


color


from


yellow


orange,


a precipitate


formed.


The


solution


was


stirred


three


hours


room


temperature.


The


solution


filtered


at 0


, affording


insertion


product


as a light


brown


powder;


yield


43.0%.


(nujol,


cm-1)


3420


3337


(UN-H),


1695


, 1674 (oc=o).


Anal.


Calcd.


for C24H36N204P2Pd


H, 6.16


4.79.


Found


,48.80; H,


6.15


4.66.


Preparation


trans-(PMe3)2U~gLC6U14CIEf


=NPh)(CCO9Me) (54)


A solution of trans-(PMe3)


2Pd(C6H4C(H)=NPh)(NHPh)


(100


DS(#),








which

was i


time


isolated


an orange


precipitate


filtration


washed


formed.


with


The


pentane


orange


precipitate


ml),


affording


of 54;


yield 40.6%.


(nujol, cm-1):


2097


('c=c).


Thermolvsis


Generate


( 1 -anilino-1.2-Z-dimethylcarboxvlate-


2-phenvlethvlene (55)


solution


0.11


mmol)


toluene


was


refluxed


hours.


Formation


a black


solid


occurred.


Solvent


was


removed


under


reduced


pressure,


remaining


residue


was


extracted


with


warm


hexane


ml).


Solvent


was


removed


under


reduced


pressure,


affording


as a dark


brown


mg);


yield


65.7%.


HRMS


(EI):


(Found)


311.11575


(Calcd.)


.11545.


Thermolysis


Generate


(N-phenyl-1


-anilino-3.4-


dimethylcarboxvlate-1


.2-dihydroisoquinoline)


solution


0.10


mmol)


toluene


was


refluxed


hours.


Formation


a black


solid


occurred.


Solvent


was


removed


under


reduced


pressure,


remaining


residue


was


extracted


warm


hexane


ml).


Solvent


removed


mg);


reduced


yield 76.4%.


pressure,


HRMS (CI):


affording


as a yellow


(Found) 415.1660 (M+1);


powder

(Calcd.)


415.1657


(M+1).


Ptea at ad


(~Zn


[Pd(PMe33 Il.E4L(5 7)


rPd(PMe )(THF)I lrBF41


a Schlenk


tube.


trans-Pd(PMe3)


S.k f,.


(166


me: 0.324


La


* *r


*I


l~i61








room


temperature,


which


time


a precipitate


formed.


The


yellow

reduced


solution


was


pressure.


filtered


The


solvent


orange-yellow


solid


was


was


removed


under


dissolved


CH2C12


room


temperature.


solution


, PMe3


was


added


(0.356


mmol


0.32


PMe3


toluene).


The


solution


color


changed


from


orange-yellow


deep


After


stirring


one


hour,


solvent


was


removed


under


reduced


ssure


, affording


as an


orange solid (132 mg);


yield 74.2%.


NMR


(CDCl3, 250C):


ppm (s,


PMe3).


31p{(1H


NMR


813.89 ppm


Compound


was


prepared


addition


one


equivalent


AgBF4


to a solution of trans


-Pd(PMe3)2


THF


room


temperature.


After


stirring


minutes


solution


was


filtered


solution


was


used


further


reaction


chemistry.


PreDaration


Me3P=NPh H2NPh


(581


solution


of [Pd(PMe3)3I] [BF4]


(1.13


2.06


mmol)


dissolved


of THF


cooled


to -60


suspension


was


added


KNHPh


(568


4.33


mmol)


as a solution


THF


C).


After


amide


was


added


solution


was


allowed


warm


room


temperature,


which


time


solution


changed


from


deep


orange-red


to dark


orange-brown.


After


stirring


hours,


solvent


was


was


extracted


removed


with


under


pentane


reduced


(2x30


pressure.


ml),


The


brown


brown


residue


solution


was








air and


moisture


sensitivity


an elemental


analysis


was


undertaken.


a procedure


identical


to that


as above


, compound


also


prepared


from


[Pd(PMe3)


2(THF)I][BF4]


equivalents


KNHPh in THF.


Preparation


Me3 P = 15NPhHi2-iN P h


a procedure


identical


to that


method


Me3P=


15NPh-H215NPh


was


prepared


from


addition


K15NHPh


[Pd(PMe3)3I] [BF4] in


THF


1H NMR (C6D6)


8 3.06 ppm


(d, JN-H=79 Hz,


15NH2,


31p NMR (C6D6)


8 3.58 ppm


(1JN.p=36


Hz).


Preparation


Presence


solution


(0.867


mmol)


was


cooled


-198


under


reduced


pressure.


After


minutes


at -198


solution


was


transferred


a C02/acetone


bath


C).


solution


was


added


KNHPh


(239


1.821


mmol)


PEt3


(4.335


mmol


10.3


of 0.42


M PEt3


toluene)


cold


(-80


THF


The solution


was


slowly


warmed


room


temperature,


which


time


fine


precipitate


formed.


After


stirring


one


hour,


solvent


was


removed


under


reduced


pressure.


The


remaining


residue


was


extracted


with


pentane


concentrated


room


temperature.


ca. 10 ml


The


cooled


extract


to 0


was filtered,

Yellow crystals


PE~L3_








Preparation


CvY3P=NPh


(6 2b


solution


trans-Pd(PCy3)2


2 (703


0.76


mmol)


AgBF4


(149


0.76


mmol)


were


placed


a Schlenk


tube


dissolved


20 ml


cold


THF


C).


The


solution


was


allowed


one


filtered


1.69


hour


cooled


mmol)


room


to -60


as a solution


temperature.


The


solution


THF


deep


was


Once


orange
added


amide


solution


KNHPh


was


was


(220


added,


solution


was


warmed


room


temperature


stirred


one


hour.


The


solution


color


changed


from


deep


orange-red


to brown-


yellow.


Solvent


was


removed


under


reduced


pressure,


remaining


brown


extracted


with


diethyl


ether


(2x20


ml).


The


deep


brown


solution


was


filtered


concentrated


Recrystallization


at 0


afforded


as an orange


powder


(147


mg);


yield 25.9%.


HRMS (EI) Calc.


for C24H38NP


.27438.


Found


.27458.


PreDaration


Me3 P=NAr


(Ar=2.6-dii


opropyvl


ohenvl)


(62)


solution


[Pd(PMe3)2(THF)I][BF4]


THF


was cooled to -60


solution


was


added


KNH-


6-IPr-C6H3 (650


3.02


mmol)


was


TIff


allowed


at -60


warm


After


to room


addition


temperature,


amide


which


solution


time


solution


solution


color


was


was


deep


stirred


red-brown


one


hour,


with


then


a fine


solvent


suspended


was


solid.


removed


The


under


reduced


pressure.


The


remaining


brown


was


extracted


with








Preparation


(Me3P)2Pd =-N C6FQ5.(3


Schlenk


tube


charged


with


1.64


mmol)


H2NC6F5


(300 mg;


1.64


mmol)


was cooled


to 0 C,


solids


were


dissolved


of THF.


solution


was


warmed


to room


temperature,


solution


became


homogeneous


dark


yellow.


After


stirring


minutes,


solution


was


cooled


to 0


solution


trans-Pd(PMe3)212


(400


0.781


mmol)


THF


was


slowly


added


to the


solution


amide


reagent.


The


solution


color


changed


to yellow-orange,


with


formation


a fine


precipitate.


After


stirring


minutes


at 0 C,


solvent


was


removed


under


reduced


ssure.


The


yellow-brown


residue


was


extracted


with


diethyl


ether


C).


The


orange


extract


was


concentrated


cooled


to 0 C.


After


several


yellow


crystals of 63 had formed.


19F{1H)


NMR


(C6D6; 25 C)


-167.72 (d, J


= 18.2),


-185.00 (t,


= 6.5),


8 -186.24 (t, J


= 19).


HRMS


(FAB)


(Calc.):


439.9913


(M+1).


(Found):


439.9946


(M+1).


Preparation


Mea PQPd =N -3 .5-(CF3 1 1 3,162)


a Schlenk


tube,


2.05


mmol)


was


ssolved


of THF


and cooled


to 0


solution


was


added


3,5-


bis(trifluoromethyl)aniline


(2.05


mmol;


2.82


0.725


THF).


solution


was


warmed


room


temperature,


solution


became


homogeneous


changed


to bright


yellow.


The


solution


was


stirred


room


temperature


until


evolution


was


no longer








warmed


brown.


to 0


The


at which


formation


time


a fine


solution


precipitate


color


was


changed


also


yellow-


observed.


After


stirring


minutes


at 0


solvent


was


removed


under


reduced


pressure.


The


yellow


residue


was


extracted


with


diethyl


ether


room


temperature.


The


yellow-brown


extract


was


filtered,


concentrated


to ca.15


cooled


to 0 C.


After


several


days,


yellow


crystals


formed


(224


mg);


yield


47%.


19F{1H}


NMR


(C6D6, 25 OC)


8 -62.98 (s).


High resolution mass


spectroscopy


(FAB)


revealed


a molecular


peak


consistent


with


phosphinimine


(304.0743


M+1).


Thermolvsis


Studie


an NMR


tube


fitted


with


a Youngs


teflon


valve,


solution


mg) in


C6D6


was


prepared.


After


hours


at 60


based on


was


1H and 31p


completely


NMR


converted


spectroscopy.


to to 64


HRMS


Pd(PMe3)4


(FAB)


(Calc.)


258.046303300


(M+1).


(Found):


8.047103300


(M+1).


an NMR


tube


fitted


with


a Youngs


teflon


valve,


solution


mg)


C6D6


was


prepared.


After


hours


at 70


was


completely


converted


to 66


based


on 1H


31p


NMR spectroscopy.


19F{1H)


NMR


(C6D6,


8 -62.72 (s, 66);


8 -62.98


[s, H2N-3,5-(CE3)2-C6H3]


Addition


PMeI


to 63


"C):








reaction


room


was


monitored


temperature,


was


NMR


spectroscopy.


converted


After


quantitatively


four


to 65


days

based


1H and 31p


Addition


NMR


Water


spectroscopy.


to 63


typical


experiment


involved


dissolving


15-20


in 0.5 ml


of C6D6


drybox.


The


NMR


tube


sealed


with


suba


seal


teflon


tape.


each


solution


was


added


one


equivalent


deoxygenated


water


syringe


followed


vigorous


shaking.


After


hours


room


temperature,


was


converted


quantitatively


O=PMe3


corresponding


aniline


based


on 1H


31p


Addition


NMR


of HCI


spectroscopy.


to 65


a Schlenk


tube,


0.08


mmol)


was


dissolved


diethyl


ether.


solution


HC1


was


added


room


temperature


(0.25


mmol;


0.25


HCI


Et20).


The


solution


immediately


changed


from


bright


yellow


to pale


yellow.


After


stirring


minutes


room


temperature,


solvent


was


removed


under


reduced


pressure.


The


NMR


spectrum


resulting


white


solid


C6D6


revealed


quantitative


conversion


65 to trans-


Pd(PMe3)2C12.


Structure


Determination


1








with


graphite


monochromator


utilizing


MoKa


radiation


--= 0.71069


reflections


with


20.000


< 28


22.000


were


used


to refine


parameters.


method.


Four


5940


reflections


reflection


(313;


were

313,


collected


132)


were


using


measured


w-scan


every


reflections


monitor


instrument


stability


(maximum


correction


was


1.01%).


option


corrections


were


applied


crystal


size


small


value


absorption


coefficient


= 8.60 cm1).


The


structure


was


solved


direct


methods


SHELXTL


63b


from


which


locations


both


atoms


were


obtained.


The


non-hydrogen


difference


Fourier


atoms


map.


The


were


obtained


structure


was


from


refined


subsequent

SHELXTL


using


cascade-matrix


least


squares.


The


BF4


anions


were


found


to be


disordered


could


refined


freely.


Two


partial


BF4


units


were


refined


asymmetric


as a rigid


unit.


The


group
non-H


each


atoms


were


anions


treated


otropically,


whereas


positions


hydrogen


their


atom


isotropic


position

thermal


were


calculated


parameters


were


ideal


fixed.


parameters


were


refined


was


minimized


o=l/(a


, o(Fo)


= 0.5 kI


1/2( [( I


+ (0.021)2


I(intensity)=


I peak


- Background


scan


I peak


background)112 (scan


rate),


correction


to decay


effects


0.02


a factor


used


to down


weight


intense


reflections


to account


instrument


instability.


The


linear


absorption








dispersion


corrections


from


Cromer


Liberman66


while


those


hydrogen


atoms


were


from


Stewart,


Davidson


Simpson67


trans-(PMe3.X2Pd(Ph)(NHPh)


(15)


Data


were


collected


room


temperature


graphite


Siemens


monochromator


R3m/V


utilizing


diffractometer


MoKa


radiation


equipped
= 0.71069


with


reflections


with


15.00


20


22.00


were


used


refine


parameters.


2865


reflections


were


collected


using


0o-scan


method.


Four


reflections


(214,


111,


102,


121)


were


measured


every


reflections


monitor


instrument


crystal


ability


(maximum


correction


was


< 0.89


Absorption


corrections


were


applied


based


on measured


coefficient


'p


crystal


10.78


faces


cm-l(min


using

. and


SHELXTL


max.


plus


transmiss


absorption


factors


0.845


0.933


, respectively).


The


SHELXTL


structure

plus 63a


was


from


solved


which


heavy


location


-atom


method


atom


was


obtained.


The


non-hydrogen


atoms


were


obtained


from


subsequent


difference


Fourier


map.


The


structure


was


refined


SHELXTL


plus


using


full-matrix


least


quares.


The


non-H


atoms


were


treated


anisotropically


whereas


positions


hydrogen


atoms


were


calculated


ideal


positions


their


isotropic


thermal


parameters


were


fixed.


parameters


were


refined


was


minimized


, o(Fo)


= 0.5


1/2 [a( I


(0.021)


} 1/2


, I(intensity)=


I peak


- Background


)(scan


rate


c o


o=l/(o


--








absorption

International


coefficient


Tables


was


-ray


calculated


from


Crystallography 64


values


from


Scattering


factors


non-hydrogen


atoms


were


taken


from


Cromer


Mann65


with


anomalous-dispersion


correction s


from


Cromer


Liberman66


while


those


hydrogen


atoms


were


from


Stewart,


Davidson


Simpson67


[(PMe )Pd(Ph)(tu


Data


were


collected


room


temperature


graphite


Siemens


monochromator


R3m/V


utilizing


diffractometer


MoKa


radiation


equipped
= 0.71069


with


reflections


with


18.00


_ 20


<22.0


were


used


refine


parameters.


4544


reflection


were


coil


cted


using


w-scan


method.


Four


reflections


(120,


002,


, 113)


were


measured


every


reflections


monitor


instrument


crystal


ability


(maximum


correction


was


< 0.97


Absorption


corrections


were


applied


based


on measured


crystal


faces


using


SHELXTL


plus


63a


absorption


coefficient,


12.7


cm-1 (min.


max.


trans


sion


factors


0.848


0.911,


respectively).


The


SHELXTL


structure


plus


was


from


solved


which


location


heavy-atom

of both Pd


method


atoms


were


obtained.


The


non-hydrogen


atoms


were


obtained


from


subsequent

independent


difference


dimers


Fourier


located


map.


at two


The


centers


structure


consists


inversion


(0,0.5,0


0,0,0.5


independent


half


dimers


asymmetric


unit).


was


refined


SHELXTL


plus


using


full-matrix


least


squares.


The


non-H


-NHPh~'1~2(32).
NHP








)2 was minimized


, o(Fo)


= 0.5 k1-1/2{[( I)]2 +


(0.021)


2 )1/2


, I(intensity)=


peak


- Background


)(scan


o(I)


S( I peak


to decay

reflections


+ I background)1/2


effects


0.02


to account


(scan


a factor


instrument


rate),


used


k is


to down


instability.


correction


weight


The


intense


linear


absorption


coefficient


was


calculated


from


values


from


International


Tables


X-ray


Crystallography 64


. Scattering


factors


non-hydrogen


atoms


were


taken


from


Cromer


Mann65


with


anomalou


-dispersion


corrections


from


Cromer


Liberman66


while


those


hydrogen


atoms


were


from


Stewart


Davidson


Simpson67


[(PMe3)Pd(CH4_C(H)


=NPh)(ut-NHPh)19 (33)


Data


were collected


room


with


temperature


graphite


Siemens


monochromator


utilizing


R3m/V


MoKa


diffractometer


radiation


equipped
0.71069


reflections


with


20.00


<20


< 22.0


were


used


to refine


parameters.


8139


reflections


were


collected


using


co-scan


method.


Four


reflections


(041,


were


means


ured


every


reflections


correction


monitor


was


instrument


1.05


crystal


Absorption


stability


corrections


(maximum


were


applied


to the


small


size


crystal


absorption


coefficient,


= 9.66 cm-1


The


structure


was


olved


heavy-atom


method


SHELXTL


63b


from


which


locations


of both


atoms


were


obtained.


The


non-hydrogen


atoms


were


obtained


from


o=l/(o








H12,

atoms


1112'


H18


H12


H18'

H18


were


refined


H18'


were


constraints.


calculated


ideal


The


methyl


positions


their


isotropic


thermal


parameters


were


fixed.


Atoms


H12'


H16


were


freely


refined


their


thermal


parameters


were


fixed.


parameters were


refined


and w (IFo


)2 was


minimized;


(o=1/(a


, ( Fo)


= 0.5 kI 1/2([C( I )]2


+ (0.021)


2 )1/2


, I(intensity)= ( I


peak


- Background


)(scan


rate


a(I)


- ( I peak


+ I background)1/2


(scan


rate),


correction


to decay


effects,


0.02


factor


used


to down


weight


intense


reflections


to account


instrument


instability.


The


linear


absorption


coefficient


was


calculated


from


values


from


International


Tables


X-ray


Crystallography 64


Scattering


factors


non-hydrogen


atoms


were


taken


from


Cromer


Mann65


with


anomalous-dispersion


corrections


from


Cromer


Liberman66


while


those


hydrogen


atoms


were


from


Stewart,


Davidson


Simpson67


r(PMew)Pd(CH3M(I


-CHPMe212 (40).
H Pm


Data


were


collected


room


with


temperature


graphite


Siemens


monochromator


R3m/V


utilizing


diffractometer


MoKa


radiation


equipped
= 0.71069


reflections


with


20.00


< 20


22.00


were


used


to refine


parameters.


2165


reflections


were


collected


using


w-scan


method


(1.2"


scan


range


3-6'


scan


speed


depending


intensity).


Four


reflections


(013,


123,


, 211)


were


measured


every


reflections to


monitor


instrument


crystal


stability


(maximum








The


plus 63a


structure


from


was


which


solved


heavy-atom


location


method


atom


was


SHELXTL


obtained.


non-H


atoms


were


located


from


a Difference


Fourier


map.


The


structure


was


refined


SHELXTL


plus


using


full-matrix


least


squares.


atoms
thermal


The


were


non-H


atoms


calculated


parameters


fixed


were


treated


idealized


at 0.08.


anisotropically.


posiotns
parameters


and
were


their i:
refined


sotropic
and Y


o (IFo


was


minimized


w=l/(o


, ( Fo)


= 0.5 kI


-1/2'" ( I


+ (0.021)


}1/2


, I(intensity)=


peak


- background


)(scan


rate


o(I)


I peak


+ I background)1/2 (


scan


rate),


correction


decay


effects


0.02


a factor


used


down


weight


intense


reflections


account


instrument


instability.


The


linear


absorption


coefficient


was


calculated


from


values


from


International


Tables


X-ray


Crystallography 64


Scattering


factors


non-hydrogen


atoms


were


taken


from


Cromer


Mann65


with


anomalous-dispersion


corrections


from


Cromer


Liberman66


, while


those


hydrogen


atoms


were


from


Stewart


Davidson


Simpson67


trans-(PMe)2Pdr(MeOOC)C=C(COOMe)(NHPh)1(Ph) (50).


Data


were


collected


diffractometer


room


equipped


temperature


with


graphite


Siemens


monochromator


R3m/V


utilizing


MoKa


radiation (X,


0.71069


32 reflections


with


20.00


S20


< 22.00


were


used


refine


parameters.


3989


reflections


were


collected


using


co-scan


method.


Four


reflections


(231,








SHELXTL


plus64a


absorption


coefficient,


= 8.20 cm-1


Minimum


maximum


transmissions


0.919


0.941


, respectively.


The


SHELXTL


structure

plus 63a


was


from


solved


which


heavy-atom


location


method


atom


obtained.


The


non-hydrogen


atoms


were


obtained


from


subsequent

SHELXTL


Difference


plus


using


Fourier


map.


full-matrix


The


least


structure


squares.


The


was


refined


non-H


atoms


treated


anisotropically.


hydrogen


atoms


were


obtained


from


Difference


Fourier


map


were


refined


with


isotropic


thermal


parameters


except


methyl


hydrogen


atoms


C19


C21


C23


which


were


calculated


ideal


positions


their


isotropic


thermal


parameters


were


fixed.


parameters


were


refined


and C to (


)2 was minimized; 0=1/(a


, o(Fo)


=0.5kI


-1/2([( I )]2


+ (0.02I)2 )1/2


I(intensity)=


I peak


- Background


)(scan


o(I)


= ( I peak


background)1/2 (scan


rate),


correction


to decay


effects


0.02


a factor


used


down


weight


intense


reflections


to account


instrument


instability.


The


linear


absorption


coefficient


was


calculated


from


values


from


International


Tables


X-ray


Crystallography 64


Scattering


factors


non-hydrogen


atoms


were


taken


from


Cromer


Mann65


with


anomalous-


dispersion

hydrogen


corrections


atoms


were


from


from


Cromer


Stewart,


Liberman66


Davidson


while


those


Simpson67


Me 3P=NPh H2NPh


(58


Data


were


collected


room








parameters.


3854


reflections


were


collected


using


c-scan


method.


Four


reflections


Instrument


were

crystal


measured


ability


every


reflections


Absorption


correction:


monitor

s were


applied


based


measured


crystal


faces


using


SHELXTL


plus64a


absorption


coefficient,


8.0.16


mm.


Minimum


maximum


transmissions


0.950


0.970


, respectively.


SHELXTL


structure

plus 63a


was


from


solved


which


heavy-atom


location


method


atom


was


obtained.


The


non-hydrogen


atoms


were


obtained


from


subsequent

SHELXTL


Difference


plus


using


Fourier


map.


full-matrix


The


least


structure


squares.


The


was


refined


non-H


atoms


treated


anisotropically


The


hydrogen


atoms


were


obtained


from


Difference


Fourier


map


were


refined


with


isotropic


thermal


parameters.


parameters


were


refined


was


minimized; w=1/(a


, o(Fo)


= 0.5 kI -1/2{ [( I)]2


+ (0.02I)2 ) 1/2


I(intensity)=


I peak


- Background


)(scan


o(I)


I peak


background)1/2 (scan


rate),


correction


to decay


effects


0.02


a factor


used


to down


weight


intense


reflections


account


instrument


instability.








Spectroscopic


Table


Data


1H NMR Dataa


compound


&na~m


muLl.


LE~z


wing


assnt


[(PMe3)3Pd(C6H4C(H)=NPr1)] [BF4] (4)C


trans-PMe3


cis-PMe3

-qCaH3
aromatic


-C(H)=N


[(PMe3)3Pd(C6H4C(H)=NPh)][BF4] (5)c


trans-PMe3


cis-PMe3
aromatic


trans-(PMe3)2Pd(C6H4C(H)=NPr1)(NHPh) (9)b


trans-PMe3


CHCH3
-N-H
-CaCH3
aromatic


-C(H)=N


trans-(PMe3)2Pd(C6H4C(H)=NPh)(NHPh) (10)b


trans-PMe3


-N-H


aromatic


-C(D)=N


trans-(PMe3)2Pd(Ph)(NHPh)


(15)b


trans-PMe3


-N-H


aromatic









Table


Cont.


compound


haa~m


mulL


LIla


mIcae


'"sin't


trans-(PMe3)2Pd(p-OCH3-C6H4)(NHPh) (18)b


trans-PMe3


-N-H


Ph-pOCH3
aromatic


trans-(PMe3)2Pd(o-NH2-C6H4)(NHPh) (19)b


trans-PMe3


-N-H
-NH2
aromatic


trans-(PMe3)2Pd[CH=C(H)C6H5](NHPh) (21)b


trans-PMe3


aromatic

aromatic


Pd-C(II


trans-(PMe3)2Pd(CH3)(NHPh) (23)b


Pd-CH3


trans-PMe3
-N-H
aromatic


trans-(PMe3)2Pd(Ph)[N(Me)Ph]


trans-PMe3


NMe
aromatic


trans-(PMe3)2Pd(Ph)(NPh2) (27)b


trans-PMe3


aromatic


(26)b









Table


. Cont.


compound


rmnlt


fLt"O


uzsignx


trans-(PMe3)2Pd(Ph)
(NH-2,6-iPr2-C6H3) (28)b


trans-PMe3
-CHCH3


-N-H


CraCH3
aromatic


trans-(PMe3)2Pd(Ph)(NHPh-p-CH3) (29)b


trans-PMe3


Ph-pCH3
aromatic


trans-(PMe3)2Pd(C6H4C(H)=NPh)
(NHPh-p-CH3) (30)b


trans-PMe3
-N-H
Ph-pCH3
aromatic


trans-(PMe3)2Pd
(C6H4C(H) =NPh)(NC4H4) (31)b


trans-PMe3


aromatic


-C(H)=N


(PMe3)Pd(Ph)(Q-NHPh)]


PMe3


aromatic


[(PMe3)Pd(CH3)(p-NHPh)]


Pd-CH3
PMe3
-N-H
aromatic


6.DDm


-caD=N


(32~b


(34~b









Table 2.1.


Cont.


compound


iDam


nulls


L~z


minte


naglnit


-C(H)=N
-N-H
ICHCH3


trans-(PMe3)Pd(C6H4CH=NPri)I (37)b


PMe3


-CHCH3
aromatic
-C(H)=N


cis-(PMe3)2Pd(CH3)(NHPh) (38)b


Pd-CH3
PMe3
PMe3
-N-H
aromatic


[(PMe3)Pd(CH3)(vi-CH2PMe2)]2 (40)b


Pd-C!H3


PMe3
PMe2


-CH2PMe


trans-(PMe 3)2Pd(Ph)(OC(O)NHPh)


trans-PMe3


aromatic


trans-(PMe3)


Pd(Ph)


trans-PMe3
&=caC


[CO(O)CHCH(0)NH(Ph)] (43)b


aromatic


14.06


trans-(PMe3)2Pd(Ph)[N(Ph)C(O)CHPh2] (45)c


trans-PMe3


-C-H
aromatic


(42)"









Table


Cont.


comDound


A. DDII


rmulL


LJ~z


InLte


li t nu


aromatic


trans-(PMe3)2Pd(Ph)
([N(Ph)C(O)NH-2,6-iPr2-C6H 3] (48)b


trans-PMe3
-CH(CtH3)2
-CH(CH3)2
aromatic


trans-(PMe3)2Pd(Ph) [N(Ph)C(O)NHPh]


trans-PMe3


aromatic


trans-(PMe3)


Pd(Ph)


(CH302C)C=C(CO2CH3)NHPh) (50)c


trans-PMe3
-CO2CH3


-CO2CH3


aromatic


trans-(PMe3)2Pd(C6H4C(H)=NPh)
(CH302CC=C(CO2CH3)(NHPh) (51)cd


trans-PMe3
trans-PMe3
-Co2CH3
-co2CH3
-Co2CH3
-CO2CH3
-N-H


-N-H
aromatic


a.n


(49>b









Table 2.1.


Cont.


compound


inn~


nulL.


LJHz

5.0


'fIng


CcktD=N


trans-(PMe3)2Pd(o-NH


6H4)


(CH302CC=C(CO2CH3)NHPh) (52)bd


trans-PMe3
PhNH2
PhNH2
-CO2CH3
-Co2CH3
-CO2CH3
-N-H
-N-H
aromatic


rrans-(PMe3)2Pd(C6H4C(H)=NPh)
(CCCO2CH3) (54)b


trans-PMe3
-CO2CH3


aromatic


1-anilino-1


,2-dimethyl


arboxylate-


2-phenylethylene


-C(H)=N
-CO2CH3
-CO2CH3
aromatic


-N-H


N-pheny


1-anilino-3,4-dimethylcarboxylate-


1,2-dihydroisoquinoline


-CO2CH3
-Co2CH3
-N-H
-C-H
aromatic


assinnt


(55)b


(56)b









Table 2.1.


Cont.


comno und


DhILLL


Uk


awsn't


Cy3P=NPh (61)c


PCy3
aromatic


Me3P=NAr (62)b


PMe3


-CH(CH3)2
-Ct(CH3)2
aromatic


(PMe3)2Pd=NC6F5 (63)b


PMe3


Me3P=NC6F5 (64)b


PMe3


(PMe3)2Pd=N-3,5-(CF3)2-C6H3 (65)b


PMe3


aromatic


Me3P=N-3,5-(CF3)2-C6H3 (66)b


PMe3


aromatic


aAll spectroscopic data was collected at 23


The multiplicity double and triplet are


apparent


splitting


patterns


the true coupling constants.


when referring to
bC6D6. CCDC13.


the PMe3


ligands and do not necessarily reflect


dThe NMR data for all isomers.


6.DDm


mteg









Table


13C(1H) NMR Dataa


compound


mulL


LIiz


assint.


[(C6H4C(H)=NPr')Pd(PMe3)3] [BF4] (4)c


trans-PMe3
cis-PMe3
-CH&(H3)2
-CH(CH3)2
aromatic


[(PMe3)3Pd(C6N4C(H)=NPh)][BF4] (5)c


trans-PMe3


cis-PMe3
aromatic







-C=N


trans-(PMe3)2Pd(C6H4C(H)=NPri)(NHPh) (9)b


trans-PMe3
-CH(C1s3)2
-CH(CH3)2
aromatic


trans-(PMe3)2Pd(C6H4C(H)=NPh)(NHPh)


(10)b


trans-PMe3


6. DDm









Table


Cont.


compound


a. ..m


mnlt


J.It


ausiguL


142.3
153.1
161.9
165.1
165.4
166.1


trans-(PMe3)2Pd(Ph)(NHPh)


(15)b


trans-PMe3


aromatic


trans-(PMe3)2Pd(p-OCH3-C6H4)(NHPh) (18)b


trans-PMe3


-OCH3
aromatic


trans-(PMe3)2Pd(o-NH2-C6H4)(NHPh) (19)b


trans-PMe3


aromatic


Pd-C


trans-(PMe3)2Pd[CH=C(H)C6HS](NHPh) (21)b


trans-PMe3


108.7
115.1
124.5


-J;Z=N









Table


Cont.


compound


mulL


LkIz


assiant.


Pd-C=C


147.6
162.4


trans-(PMe3)2Pd(CH3)(NHPh) (23)b


Pd-CHI3


trans-PMe3


108.4
115.1
129.1
162.7


aromatic


trans- (PMe3)2Pd(Ph) [N(Me)Ph]


trans-PMe3


NCH3


trans-(PMe3)2Pd(Ph)(NPh2) (27)b


trans-PMe3


aromatic


trans-PMe3


trans-(PMe3)2Pd(Ph)
(NH-2,6-iPr2-C6H3) (28)b


trans-(PMe3)2Pd(Ph)(NHPh-p-CH3) (29)b


trans-PMe3


Ph-CH3


8, DDm


(26)b








Table


Cont.


compound


L. nm


mulL


UkI


assint.


157.5


trans-(PMe3)2Pd(C6H4C(H)=NPh)
(NHPh-p-CH3) (30)b


Pd-C

trans-PMe3
Ph-pCH3
aromatic


trans-(PMe3)2P d
(C6H4C(H)=NPh)(NC4H4) (31 )b


116.5
121.0
122.5
125.4
128.6
129.6
137.3
142.2
153.3
159.9
165.1
165.3

12.6
107.8
121.0
122.6
125.6
126.9
129.1
129.4
131.1
137.5
141.7
153.2
164.9


-I-fl


trans-PMe3


aromatic


-C=N


[(PMe3)Pd(CH3)(X-NHPh)]


Pd-II3
PMe3
aromatic


117.0
121.8
122.6
128.0


N-isopropyl-2-anilino


benzaldimine


61.4
112.8
116.9
118.7
121.5
122.6
129.3
i1n a


-CHCCH3)
-cHCirH3)2


(34)b


(35)b









Table


Cont.


compound


nudLt


LJIz


asint


114.6


cis-(PMe3)2Pd(CH3)(NHPh) (38)b


107.0
115.4
129.1
163.0


Pd-CH3
PMe3
PMe3
aromatic


trans-(PMe3)2Pd(Ph)[OC(0)NHPh] (42)c


trans-(PMe3)2Pd(Ph)
[OC(O)CHCH(0)NH(Ph)] (43)b


trans-PMe3


aromatic


116.9
119.8
122.2
127.2
128.3
135.7
142.0
148.4
158.9

12.2
119.6
122.9
123.1
127.6
128.9
133.4
134.5
135.9
140.5
149.1
163.3
171.6


-C=o

trans-PMe3
aromatic


-c=o
-C=O


trans-(PMe3)2Pd(Ph)[N(Ph)C(O)CHPh2] (45)c


trans-PMe3


62.8
120.6
122.8
123.9
126.0
127.2
127.7
128.0
128.3
128.7
128.8
129.3
136.6
1 ')


aromatic
aromatic


g~ DDm









Table


Cont.


compound


isoa


mulL


Lt~z


uzisinL


trans-(PMe3)2Pd(Ph)[N(Ph)C(O)NHBut] (47)b


trans-PMe3


-C(CH3)3
-C(CH3)3
aromatic


Pd-C
-C=O


trans-(PMe3)2Pd(Ph)
[N(Ph)C(O)NH-2,6-iPr2-C6H3] (48)b


trans-PMe3
-CH(CH3)2
-CH(CH3)2
aromatic


trans-(PMe3)2(Ph) [N(Ph)C(O)NHPh]


trans-PMe3


aromatic


Pd-C
-C=0


trans-(PMe3)2Pd(Ph)


trans-PMe3
-Co2CH3


(CH302CC=C(CO2CH3)NHPh) (50)c


-C02Q13
aromatic


(49)b









Table


Cont.


compound


Lp am


unait


J.Hz


ausignL


Pd-C
-C=O
Pd-C=C
-C=O


trans-(PMe3)2Pd(C6H4C(H) =NPh)
(CH302CC=C(CO2CH3)NHPh) (51)cd


trans-PMe3
trans-PMe3


-Co2CH3
-co c3
-C02CH3
-C 02CH3
-C02CH3
aromatic


Pd--=C
Pd-C=C
aromatic


Pd-C
Pd-C
-C=O
-C=O
-C=N
-C=N


42=0
42=0









Table


Cont.


cnfl1D.ohlfl.d


rmMlt


LHz


assient.


-C=O
-c~o
-c=o


trans-(PMe3)2Pd(C6H4C(H)=NPh)
(CCCO2CH3) (54)b


trans-PMe3
-C02 I3


-C=N
-C=O


1 -anilino- 1,2-dimethylcarboxylate-


2-phenylethylene


-C02C 3
-CO2CH3
aromatic


6. DDm


(55)b









Table


Cont.


compound


nmul


LJIz


lassiaL


N-phenyl- 1 -anilino-3,4-dimethylcarboxylate-


1,2-dihydroisoquinoline


73.3
108.9


-CO2SH3
-CO 2CH3
-C-H
aromatic


119.8
124.7
125.4
125.6
126.2
128.4
128.7
129.0
129.3
140.8
144.2
144.6
164.6
166.2


Me3P=NPh.H2NPh (58)b


C=C
aromatic
-C=O


PMe3


aromatic


114.7
116.7
118.0
122.5
122.8
129.1

11.0


(PMe3)2Pd=NC6FS (63)b


PMe3


(PMe3)2Pd=N-3


,5-(CF3)2-C6H3 (65)b


PMe3


102.5
113.7
159.6


aAll spectroscopic data was collected at


aromatic


The multiplicity doublet and triplet are


apparent


splitting


patterns


when


reflect the true coupling constants.


referring
bC6D6.


to the PMe3


CCDCl3.


ligands and


do not necessarily


dThe NMR data for all isomers.


8. DDm


(56)b









Table 2.3.


31p{IH) NMR Dataa


compound


mMIlt


Lilt


[(PMe3)3Pd(C6H4C(H)=NPrt)] [BF4] (4)C


[(PMe3)3Pd(C6H4C(H)=NPh)] [BF4] (5)c


trans-(PMe3)2Pd(C6H4C(H)=NPr')(NHPh) (9)b


-19.53
-28.06


-19.64
-27.46


-16.87


trans-(PMe3)2Pd(C6H4C(H)=NPh)(NHPh)


(10)b


trans-(PMe3)2Pd(Ph)(NHPh)


trans-(PMe3)2Pd(p-OCH3-C6H4)(NHPh) (18)b

trans-(PMe3)2Pd(o-NH2-C6H4)(NHPh) (19)b

trans-(PMe3)2Pd[CH=C(H)C6H5](NHPh) (21)b

trans-(PMe3)2Pd(CH3)(NHPh) (23)b


trans-(PMe3)2Pd(Ph)[N(Me)Ph]


trans-(PMe3)2Pd(Ph)(NPh2) (27)b


trans-(PMe3)2Pd(Ph)


(NH-2,6-'Pr


-16.77

-16.79


-16.28

-14.81

-16.26

-14.15


-15.06


-17.31


-18.43


-C6H3) (28)b


trans-(PMe3)2Pd(Ph)(NH-Ph-p-CH3) (29)b


trans-(PMe3)2Pd(C6H4C(H)=NPh)
(NHPh-p-CH3) (30)b


trans-(PMe3)2Pd(C6H4C(H)=NPh)
(NC4H4) (31)b


[(PMe3)Pd(Ph)(>-NHPh)]2 (32)bd


-16.37


-16.63


-16.55


-11.12
-12.12
-15.04


[(PMe3)Pd(CH3)(X-NHPh)]2 (34)b,d


(15)b


(26)b








Table 2.3.


Cont.


compound


La~m


milL.


L~Jz


[(PMe3)Pd(CH3)(X-CH2PMe2)]


trans-(PMe3)2Pd(Ph)(OC(O)NHPh) (42)c


trans-(PMe3)2Pd(Ph)
[CO(O)CHCH(0)NH(Ph)] (43)b


trans-(PMe3)2Pd(Ph)[N(Ph)C(O)CHPh2] (45)c

trans-(PMe3)2Pd(Ph)[N(Ph)C(O)NHBut] (47)b

trans-(PMe3)2Pd(Ph)
[(N(Ph)C(O)NH-2,6-iPr2-C6H 3] (48)b


trans-(PMe3)2Pd(Ph) [N(Ph)C(O)NHPh


trans-(PMe3)2Pd(Ph)


-14.04
-19.97


-16.22


-17.46


-18.40

-17.07

-17.66


-17.27


-16.67


(CH302CC=C(CO2CH3)NHPh) (50)c


trans-(PMe3)2Pd(C6H4C(H)=NPh)
(CH302CC=C(CO2CH 3)(NHPh) (51)cd


trans-(PMe3)2Pd(o-NH2-C6H4)
(CH302COC=C(CO2CH3)NHPh) (52)bd


trans-(PMe3)2Pd(C6H4C(H)=NPh)
(CCCO2CH3) (54)b


-16.76
-17.92


-15.75
-15.82


-17.31


Me3P=NPh-H2NPh (58)b


Cy3P=NPh (61)c


35.28


Me3P=NAr (62)b


-15.74


(PMe3)2Pd(NC6F5) (63)b


Me3P=NC6F5 (64)b


13.76


(PMe3)2Pd[N-3,5-(CF3)2-C6H3] (65)b


-9.16


Me3P=N-3,5-(CF3)2-C6H3 (66)b


(40)6


(49>b













CHAPTER 3
SYNTHESIS AND CHARACTERIZATION
OF PALLADIUM(II) AMIDE COMPLEXES


discussed


well-characterized


Chapter


palladium(II)


there


amide


are only


a limited


complexes.


number


Although


there


several


stable


nickel(II)


platinum(II)


complexes


that


have


been


isolated


preparation


stable


palladium(II)


amide


complexes


with


little


success.


Our


research


interests


have


been


directed


toward


synthesis


stable


monomeric


palladium(II)


amide


complexes.


first


section


Chapter


synthesis


characterization


variety


monomeric


palladium(II)


amide


complexes


presented.


The


ancillary


ligand


as well


substituent


effects


on the


amido


group


metal


center


will


discussed


with


regard


amide


stability.


The


second


third


sections


Chapter


3 focus


on the


thermal


stability


Pd-N


bond.


The


tendency


monomeric


palladium(II)


elimination


amide


amide


will


complex


understanding


final


complexes

emphasized.


investigated


thermal


section


dimerize


Thermoly


order


stability

Chapter 2


undergo

selected


gain


these


reductive


monomeric


a better


amide


synthesis


complexes.


and








stable


amide


complex


may


provide


further


information


regarding


thermal


stability


palladium(II)


amide


complexes.


The


reactivity


amide


complex


other


related


chemistry


will


also


discussed


greater


detail.


Synthesis


Characterization


Monomeric


Palladium(II)


Amide


Complexes


Addition


Nucleophiles


Cationic


Ortho-metalated


Palladium(II)


Complexes


Chapter


transition-metal


amido


variety


complex


methods


was


cussed.


preparation

Although


late-


methods


presented


Chapter


are the


most


common


, they


are not


only


means


to generate


new


M-N


bonds.


Indeed,


with


scarcity


late-transition-metal


amide


complexes


literature,


other


approach


preparation


these


complexes


must


investigated.

conventional


Our


research


approaches


interests


involve


synthesi


development


class


non-


compounds.


One


such


approach


seen


been


established


that


coordination


unsaturated


organic


ligands


transition


metal


actvates


ligand


toward


nucleophilic


attack.6 8


This


approach


to the


preparation


a variety


NLnM-N


LnM-N


C-Nu








complexes.


The


ortho-metalated


addition


ruthenium


a variety

complex ]


nucleophiles


resulted


to the


cationic


tereospecific


nucleophilic

ruthenium(II)


confirmed


attack


amide


that


imnme


complex


nucleophilic


carbon


(eq.


attack


generate


3.2).70


occur


The


neutral


crystal


at the


imine


structure


carbon,


'I \


CH3lI


NPh
N


(3.2)


with


formation


new


Ru-N


bond.


The


Ru-N


bond


distance


2.08(2)


was


consistent


with


M-N


bond


distances


other


monomeric


late-tran


ition-metal


amide


complexes.32b,35g


The


nucleophilic


successful


attack


generation

an imine


ruthenium


ligand


amide


coordinated


complexes


a cationic


metal


center


represented


prompted


to investigate


approach


with


other


late-transition


metal


The


facile


preparation


ortho-metalated


palladium(II)


comply


exes


literature


well


known.


The


addition


a nucleophile


to a


cationic


ortho-metalated


imine


complexes


palladium(II)


could


generate


new


Pd-N


bonds.


The


synthesis


first


cationic


complex


palladium(II)


~Jf: ,P








immediate


addition


precipitation


equivalents


AgBF4


chloride-bridged
to a solution of 2


dimer


The


in CH3 C N


afforded


3 as


a yellow-orange


Addition


three


equivalents


PMe3


to 3


CH2C12


resulted


quantitative


conversion


to the


five-


coordinate


solution


cation


at 25


Compound


The


4 is


compound


air-stable


was


solid


characterized


state


with


13C, and 31p


NMR


spectroscopy.


The


31p(1H)


NMR


spectrum


shows


a doublet


consistent


with


a triplet

pseudo-


a 2:


ratio


(2Jp..p


quare-pyramidal


= 42


and is


structure


compound


[(C6H4C(H)=NPh)Pd(PMe3)3][BF4](5)


was also prepared in


a manner


identical


to that


Figure


with


spectroscopic


data


consistent


with


that


compound


Nucleophilic


attack


on the


imine


carbon


was


next


investigated.


The


addition


CH3Li


to a solution


4 in


THF


at -60 C


subsequent


warming


room


temperature


afforded


palladium


methyl


complex


6 (eq.


3.3).


The


NMR


spectrum


revealed


a broad


singlet


at 0


ppm


protons


methyl


SNPr PMe3

P d --PMe3

Me3P


CH3Li


.SNPrPMe
PMe3

Pd-CH3

Me3P


group


bonded


to palladium.


Retention


imine


proton


singlet


(3.3)









NPr1


2 Pd(OAc) 2


d" OAc
Pd


AcOH


acetone
NaCl(aq)


IPr1 \
Pd


2
2


AgBF4
CH3CN


NPr1
Pd(NCCH 3)2


+BF4


3 PMe3
CHa-I,c


Figure


PMe3
Pd- PMe3


The synthesis of


+BF4








The


crystal


structure


may


explain


why


nucleophilic


attack


was


observed


consisted


at the


metal


well-separated


center.


anions


crystal

cations.


structure


The


thermal


ellipsoid


drawing


4 is


found


Figure


while


selected


bond


lengths


angles


found


Table


Table


Selected


bond


lengths


angles


-P(1)
-P(2)
-P(3)
-C(1)


N-C(7)
N-C(8)


2.324(3)
2.325(3)
2.360(3)
2.048(7)
1.238(13)
1.457(15)
2.779(3)


P(1)
P(1)
P(2)


P(1)-Pd


P(3)


-P(2)
-P(3)
-P(3)
-C(1)
-C(1)
-C(1)


.0(1)


96.3(1)
96.2(1)
83.0(2)


7(2)


174.6(2)


The


PMe3


cations


have


group


pseudo-:
: phenyl


quare-pyramidal


group


occupying


geometry


sites


with


basal


plane


imine


distance


nitrogen


2.78


occupying


is extremely


apical


long


position.


suggests


The


a very


Pd-N


weak


bond


Pd-N


interaction.


distance


typical


Pd-N


distances


related


five-


coordinate


compounds.


The


Pd-P


distances


show


strong


trans


influence


phenyl


group,


which


was


consistent


with


observed


chemistry.


The


-Pd-P2


angle


angle


165


was


bent


toward


less


sterically


demanding


phenyl


group.


The


remaining


bond


length


angle


within


expected


range


Pd-N


bond


length


in complex


suggested


imine





























O
r
C-)








value


differs


15-20


ppm


from


that


observed


other


ortho-


metalated


definitely


benzaldimine


bound


complexes


metal73


which


suggested


atom


that,


was


solution,


atom


may


not be


coordinated


, making


metal


center


most


likely


nucleophilic


attack.


The


use


bidentate


phosphine


ligands


will


generate


a four-


coordinate


complex,


therefore


forcing


imine


nitrogen


coordinate


to the


cationic


metal


center.


The


addition


of DMPE


[1,2-


bis(dimethylphosphino)ethane]

bis(diphenylphosphino)ethane]


DPPE


solution


[(C6H4CH=NPh)Pd(NCCH3)2][BF4] in CH2C12 afforded compounds 7


8 respectively.


addition


nucleophiles


CH3-


CH30-


to compounds


7 and 8


resulted


formation


intractable


products


3.4).*


One


possible


explanation


difference


reactivity


between


cationic


ruthenium


palladium


complexes


with


nucleophiles


may


involve


teric


hindrance.


The


metal


center


cationic


ruthenium


complex


in eq.


was


guarded


against


nucleophil

therefore


attack


rendering


PMe


imine


carbon


hexamethylbenzene


susceptible


ligands,


nucleophilic


attack.


The


metal


center


compounds


and


however


*Doufou, P.


Boncella, J.


unpublished


results.











intractable
products


R2
P



R2


(3.4)


= Me
=Ph


surrounded


bulky


ligands,


therefore


cationic


metal


center


was


exposed


susceptible


nucleophilic


attack.


Addition


Amide


Reagents


to Cationic


Neutral


Palladium(II)


Complexes


Preferential


attack


at the


metal


center


suggests


amide


addition


reagents


of KNHPh


employed

a solution


to generate


4 in


THF


new


at -60


Pd-N


bonds.


The


OC resulted in


nucleophilic


attack


metal


center


generation


amide


complex


9 (eq.


3.5).


Although


compound


9 is


air-sensitive,


,^ t PMe3

- Pd-PMe3

3P


KNHPh


/s11 PMe3

Pd NHPh

Me3P


-Pr'
=Ph


= Prh
- Ph


-U..-~ -


(3.5)


_...~~_lt


m


r


I


1








0.71


ppm


1.61


ppm


PMe3


N-H


protons


respectively


(Figure


3.3).


singlet


31p(1H}


NMR


spectrum


-16.87


ppm


confirmed


trans


stereochemistry


about


metal


center.


The


group


imine


nitrogen


was


restricted


to alkyl


substituents.


prepared


consistent


with


an identical


addition


procedure,


of KNHPh


formation


to 5 (eq.


with


amide


3.5).


a broad


complex

All NMR


singlet


was


data


at 1.53


was


ppm


for the


N-H


proton


NMR


spectrum.


The


provided


amido


reactions


addition


a convenient


complexes.


are a common


KNHPh


to cationic


method


was


discussed


route


palladium(II)


preparation
n Chapter 1

synthesis of


complexes
palladium


transmetallation


late-transition-


metal


amide


complexes.


The


majority


these


reactions


involve


addition


an amide


reagent


a metal


halide


complex,


with


chloride


ion as the


leaving


group.


order


to understand


limitations


transmetallation


reactions


addition


amide


reagents


neutral


palladium(II)


complexes


was


investigated.


preliminary


reaction


between


neutral


palladium(II)


complex


KNHPh


found


addition


of KNHPh


result


NPrPMe3

-Pd-GO

Me3P


formation


KNHPh


x


amide


complex


NPr PMe3


-4
Pd-NHPh


The


(3.6)
















































a)


rz


0a

z
I
'0
pi ___


--- I


-;i








lack


amide


formation


suggests


nature


leaving

recently


group


may


demonstrated


dictate


that


extent


addition


amide


formation.


NaNHPh


Trogler


(PEt3)2Pt(H)C1


not result


amide


formation,


however


when


leaving


group


was


nitrate


ion,


formation


a thermally


stable


platinum

chloride


amide


complex


was


was


observed


an appropriate


3.7).32b


leaving


group


Although


in eq.


3.6,


synthesi


NaNHPh


to the


palladium(II)

hydridochloro


amide


palladium


complexes


addition


complexes


was


trans-(PEt3)2Pt(H)Cl
+
NaNHPh


trans-(PEt3)2Pt(H)(NHPh )


(3.7)


trans-(PEt3)2Pt(H)N03
+
NaNHPh


recently


reported


3.8).30a


The


chloride


these


complexes


a better


leaving


group


to the


strong


trans


effect


hydride


molety

results


The


in a s


weaker


stronger


trans


Pd-C1


effect


bond


exerted


as compared


phenyl


group


to the


Pd-Cl


bond


hydridochloro


palladium


complexes


therefore


displacement


chloride


amide


reagent


may


possible.


The


lack


reactivity


prompted


us to investigate


to trans-


w


I











L
I
H-Pd-Cl


NaNHPh


H- P d -NHPh


(3.8)


L= PCy3, P'Pr3


compound

compound
complex 1

complex 1


allowed


was


was


generated


also


THF


to react


31%


generated


3.9).


The


with


KNHPh


isolated


yield.


addition


generation


THEFT


at -60


amide


KNHPh


compounds


to the


iodo


9 and 10


4NR PMe3

Sd d--I

Me3P


KNHPh


=Pr
= Ph


""a PMe3

Pd--- NHPh

Me3P


(3.9)


- Pr'
= Ph


from


neutral


cationic


palladium(II)


complexes


demonstrated


that


nature


leaving


group


control


extent


amide


formation.


The


addition


KNHPh


to cationic


palladium(II)


complexes


resulted


displacement


equivalent


PMe3


formation


Pd-N


bonds.


Phosphines


are generally


considered


good


leaving


groups;


however,


their


ability


behave








Synthesis


Characterization


Substituted


Phenvl.


Vinyl.


Alkvl


Palladium(II)


Amide


ComDlexes


Compounds


9 and


are stable


complexes


room


temperature
complexes


solid


state


unstable


solution


more


however


elevated


amide


temperatures.


high


examined


degree


what


stability


influence


9 and


substituent


was


intriguing,


trans


therefore


amido


group


overall


stability


palladium(II)


amide


complexes.


The


presence


mine


functionalities


9 and


may


enhance


stability


these


complex


The


crystal


structure


confirmed


that


there


was


a weak


interaction


between


metal


center


imine


nitrogen.


order


understand


what


effect


imine


prepare


functionality


palladium


amide


on amide


complexes


stability,

without 1


was n

imine


necessary


functionlity


The


compound


trans-(PMe3 )2Pd(Ph)I


(14)


was


conveniently


prepared


addition


to Pd(PMe3 )4 in


pentane.


The


addition


equivalents


of KNHPh


a solution


trans-


(PMe3)2Pd(Ph)I


THF


-78C


afforded


amido


complex


trans-


(PMe3)2Pd(Ph)(NHPh)(15)


as yellow


crystals


3.10).


NMR


PMe3


PMe3


Ph--Pd

Me3P


KNHPh


Ph-- Pd-NHPh


Me3P








a well


defined


phenyl


region


(Figure


3.4).


15N-enriched


sample


was


confirmed


prepared,
formation


a doublet


Pd-N


at 1.66


bond.


ppm


The


(1JN-H


presence


singlet at
a virtual
13C(1H)


-16.79


triplet


NMR


palladium


ppm


in the


157.1


spectrum


confirmed


31p(1H)


ppm


NMR


(apparent JP-C


ipso


trans


carbon


stereochemi


spectrum


as well as


= 12.2


phenyl

about 1


ring


bound


metal


center.


Crystallization


from


diethyl


ether


at 0


afforded


crystal


suitable


an X-ray


diffraction


study


The


thermal


ellipsoid


drawing


found


Figure


while


selected


bond


lengths


angles


found


Table


Pd-N


bond


distance


2.116


(13)


A was


consistent


with


Pt-N


Ir-N


bond


distances


Table


Selected


bond


lengths


angles


-P(1)
-P(2)


Pd-C(11)
N-C(21)


2.301(4)
2.300(4)
2.116(13)


2.03(


.32(2)


P(1)
P(1)


P(2)
P(1)


-P(2)


-C(11)
-C(11)


d-C(11)
1)-Pd-N


169.45(13)


95.3(3)
90.5(3)
87.9(4)
86.8(4)
176.5(4)
130.4(9)


previously


reported


amide


complex


xes.


29c.3


The


expected


trans


square-planar


geometry


about


palladium


was


observed


with


phosphine


ligands


bent


toward


sterically


demanding


phenyl


= 69
































































Ur)


I


J