Synthesis of palladium and platinum complexes containing the multidentate ligands PPh2CH2(tBu)=N-N=C(R)Q (R = H, Me; Q = 2-pyridine, 2-thiophene, o-BrC6H4). Crystal structure of [PtMe{PPh2CHC(tBu)NNCMe(2-py)-κ 3N,N′,P}] and [PdBr{PPh2CH2C(tBu)=N-N=CHC6

Article abstract of DOI:10.1016/S0022-328X(99)00290-9

The reaction of PPh₂CH₂C(^tBu)=NN=CMe(NC₅H ₄) (1) with [Pt₂Me₄(μ-SMe₂)₂] gave the six-membered metallacycle [PtMe₂{PPh₂CHC(^tBu)NNCMe(2-py)-κ ²N,P}] (4) which was converted into [PtMe{PPh₂CHC(^tBu)NNCMe(2-py)-κ ³N,N′,P}] (5) at elevated temperature. Treatment of the methyl platinum complex 5 with an excess of MeI gave [PtMe₂I{PPh₂CHC-(^tBu)NNCMe(2-py)-κ ³N,N′,P}]. A similar reaction of PtMe₂(cod) with [PPh₂CH₂C(^tBu)=NN=C(HSC₄H ₃] (2) also afforded PtMe₂{PPh₂CH₂C(^tBu)NNC(H)SC ₄H₃-κ²N,P} (7). The prolonged heating of 7 led to decomposition rather than the cycloplatination product. The treatment of 2 with PtCl₂(cod) in the presence of NEt₃ gave the deprotonated platinum(II) complex [Pt{PPh₂CH=C(^tBu)N-N=C(H)SC₄H ₃-κ²N,P}₂] (8) containing an ene-hydrazone backbone. The cyclopalladated metallacycle [PdBr{PPh₂CH₂C(^tBu)=N-N=CHC₆H ₄}-κ³C,N,P] (9) has been prepared by the oxidative addition of the o-halo-substituted phosphino hydrazone derived from PPh₂CH₂C(^tBu)=N-N=C(H)(o-BrC₆H ₄) (3) to Pd₂(dba)₃. These new complexes have been characterized by ¹H-, ¹³C-, and ³¹P-NMR, and elemental analyses. The molecular structures of 4, 5 and 9 have been determined by a single-crystal X-ray diffraction study.

Full text of DOI:10.1016/S0022-328X(99)00290-9

www.elsevier.nl/locate/jorganchem
Journal of Organometallic Chemistry 587 (1999) 165–175
Synthesis of palladium and platinum complexes containing the
multidentate ligands PPh2CH2(tBu)ꢀNꢁNꢀC(R)Q (R=H, Me;
Q=2-pyridine, 2-thiophene, o-BrC6H4). Crystal structure of
[PtMe{PPh2CHC(tBu)NNCMe(2-py)-k3N,N%,P}] and
[PdBr{PPh2CH2C(tBu)ꢀNꢁNꢀCHC6H4}-k3C,N,P]
Chunghun Lee a, Youngjin Kang a, Sang Ook Kang a,1, Jaejung Ko a,*,
Jung Whan Yoo a, Moon Hwan Cho b
a Department of Chemistry, Korea Uni6ersity, Chochiwon, Chungnam 339-700, South Korea
b Department of Chemistry, Kangwon National Uni6ersity, Chuncheon 200-701, South Korea
Received 9 February 1999; received in revised form 20 May 1999
Abstract
The reaction of PPh2CH2C(tBu)ꢀNNꢀCMe(NC5H4) (1) with [Pt2Me4(m-SMe2)2] gave the six-membered metallacycle
[PtMe2{PPh2CHC(tBu)NNCMe(2-py)-k2N,P}] (4) which was converted into [PtMe{PPh2CHC(tBu)NNCMe(2-py)-k3N,N%,P}] (5)
at elevated temperature. Treatment of the methyl platinum complex 5 with an excess of MeI gave [PtMe2I{PPh2CHC-
(tBu)NNCMe(2-py)-k3N,N%,P}]. A similar reaction of PtMe2(cod) with [PPh2CH2C(tBu)ꢀNNꢀC(HSC4H3] (2) also afforded
PtMe2{PPh2CH2C(tBu)NNC(H)SC4H3-k2N,P} (7). The prolonged heating of 7 led to decomposition rather than the cycloplatina-
tion product. The treatment of 2 with PtCl2(cod) in the presence of NEt3 gave the deprotonated platinum(II) complex
[Pt{PPh2CHꢀC(tBu)NꢁNꢀC(H)SC4H3-k2N,P}2] (8) containing an ene-hydrazone backbone. The cyclopalladated metallacycle
[PdBr{PPh2CH2C(tBu)ꢀNꢁNꢀCHC6H4}-k3C,N,P] (9) has been prepared by the oxidative addition of the o-halo-substituted
phosphino hydrazone derived from PPh2CH2C(tBu)ꢀNꢁNꢀC(H)(o-BrC6H4) (3) to Pd2(dba)3. These new complexes have been
1
characterized by H-, 13C-, and 31P-NMR, and elemental analyses. The molecular structures of 4, 5 and 9 have been determined
by a single-crystal X-ray diffraction study. © 1999 Elsevier Science S.A. All rights reserved.
Keywords: Phosphino hydrazone; Palladium; Platinum; Crystal structure; Cyclization
Moreover, there is an increasing interest in the palladium-
(II) and platinum(II) complexes with terdentate ligands
such as PNN [6], PNC [7], SNC [8], and PNP [9].
Recently, Shaw and co-workers have described the
synthesis of the phosphino hydrazone Z-Ph2-
PCH2C(tBu)ꢀNNH2 (L) [10] and its extensive chemistry
[11]. Compound L easily undergoes condensation with
aldehydes and ketones to give azines. We reasoned
that the condensation of 2-acetylpyridine or 2-thio-
phenecarbaldehyde with L ought to give a new ligand
that can coordinate to the palladium or platinum as a
terdentate ligand. This proved to be the case. These
ligands attracted our attention because they contain the
two tautomeric forms such as an azinelene-hydra-
zone, i.e. a 1,3-proton shift and the intrinsic flexibility
1. Introduction
In recent years, cyclometalated compounds with mul-
tidentate ligands have been extensively studied because
of their potential utility in organic synthesis [1], and a
number of their synthetic approaches have been investi-
gated [2]. Among these, the palladium and platinum
complexes with multidentate ligands are especially in-
teresting because of their catalytic activity [3]. It has
recently been found that PꢁN ligands, in particular, are
suitable ligands for palladium or platinum-catalyzed
cross-coupling reactions [4] and allylic alkylation [5].
* Corresponding author. Fax: +82-415-8675396.
1 Also corresponding author.
0022-328X/99/$ - see front matter © 1999 Elsevier Science S.A. All rights reserved.
PII: S0022-328X(99)00290-9

166
C. Lee et al. / Journal of Organometallic Chemistry 587 (1999) 165–175
of the ligands facilitates the adaptation of the bite
angles between the metal and the donor atoms. In
addition, we are interested in conducting a systematic
study of the use of terdentate ligands obtained by
replacing the pyridine moiety with 2-bromobenzene. As
part of our continuing studies on the synthetic utility
and understanding of the uncommon coordination ge-
ometry of multidentate ligands [12], we attempted to
synthesize a variety of palladium and platinum com-
plexes. We now report the synthesis, reactivity, and
characterization of the palladium and platinum com-
plexes of the multidentate ligand and the single-crystal
X-ray structures of three such compounds.
methylene carbon appears as a doublet with coupling
2J(PC)=26.1 Hz in the 13C-NMR spectrum. We sug-
gest that ligands 1–3 have the anti configuration
around the CꢀN bond as do the several complexes
derived from them.
2.2. Synthesis and characterization of complexes from
the ligand 1
The reaction of [Pt2Me4(m-SMe2)2] with ligand 1 in
toluene afforded a greenish–yellow solid 4 which
showed the common pattern for a ‘PtMe2’ cis arrange-
ment with the corresponding loss of SMe2. The product
4 was also prepared by the reaction of PtMe2(cod) and
ligand 1 in high yield. However, the product could not
be isolated in pure form, since a further reaction oc-
curred to give the cyclization product even at room
temperature (r.t.). When the reaction was carried out at
elevated temperature, it gave rise to the nitrogen coor-
dination product PtMe{PPh2CHC(tBu)NNCMe(2-py)-
k3N,N%,P} (5) (Scheme 1).
These reactions are expected to proceed by ligand
substitution to give the corresponding dimethyl(PN)-
platinum(II) complex followed by elimination of
methane from PtꢁMe and an NꢁH bond formed by the
involvement of an azinelene-hydrazone tautomerism.
The isostructural complex, PtCl{PPh2CHC(tBu)-
NNCMe(2-py)-k3N,N%,P} (6) has been synthesized
from the reaction of PtCl2(cod) with 1 in toluene (Eq.
(1)).
2. Results and discussion
2.1. Synthesis and characterization of the ligands
The phosphino-N-acetylpyridine hydrazone PPh2-
CH2C(tBu)ꢀNNꢀCMe(NC5H4) (1) was prepared by the
condensation of hydrazone phosphine PPh2CH2C-
(tBu)ꢀNNH2 with 2-acetylpyridine in hot methanol.
The azine ligands PPh2CH2C(tBu)ꢀNNꢀCHQ (Q=2-
thiophenecarboxaldehyde 2; 2-bromobenzaldehyde 3)
were similarly prepared. Ligands 1–3 were character-
ized by 1H-, 13C- and 31P-NMR, IR and elemental
analysis. The 31P{1H}-NMR spectrum of 1 showed a
singlet at l −10.78, which is in agreement with similar
diarylphosphine ligands. The resonance of the
(1)
Scheme 1.

C. Lee et al. / Journal of Organometallic Chemistry 587 (1999) 165–175
167
1
Compounds 4–6 were characterized by H-, 13C- and
2.3. Description of the molecular structures of 4 and 5
31P-NMR, mass spectrometry and elemental analysis.
The structures of 4 and 5 were determined by single-
crystal X-ray diffraction. The NMR spectroscopic data
for 4 and 5 are consistent with the solid-state structure
as determined by X-ray crystallography. In the
1H-NMR spectrum of 4, the resonances of the methyl
groups bound to platinum gave rise to two signals at l
0.62 and −0.06 with 2J(PtH) values in the range 70–90
Hz, as reported for analogous compounds [13]. The
coupling constant values with 2J(PtH)=90.4 and
2J(PtH)=69.6 Hz are assigned to the methylplatinum
trans to the imine and phosphorus, respectively, since
phosphorus has the stronger trans influence. These are
typical values for methylplatinum(II) complexes [14].
The presence of two PtꢁCH3 bonds was further proved
by the observation of two resonances in the 13C-NMR
spectrum at 7.62 and 1.22 ppm, which couple with 31P
and 195Pt. The methylene CH2P protons gave two peaks
Suitable crystals of 4 and 5 were grown in toluene–
hexane solution. Details of the X-ray data collection
and structure refinement for complexes 4 and 5 are
presented in Table 1. The molecular structure and
atom-numbering schemes for 4 and 5 are given in Fig.
1 and Fig. 2, respectively. Selected bond distances and
angles are given in Table 2. The crystal structure of 4
consists of discrete molecules separated by van der
Waals distances. The platinum atom of 4 is in a slightly
distorted square-planar environment coordinated to
phosphorus, two carbons, and iminic nitrogen atom.
The iminic nitrogen and the phosphorus adopt a cis
arrangement. The ligandꢁplatinum distances are close
to other platinum complexes containing six-membered
phosphinoꢁimino chelates [15]. The PtꢁC(30) distance
,
of 2.061(10) A is relatively short, probably due to the
better p-accepting capacity of the trans-situated imino
nitrogen N9.
2
3
at l 3.55 and 2.51 with J(PH)=2.1 and J(PtH)=
21.6 Hz, demonstrating that the methylene protons are
diastereotopic. The complex showed a single resonance
in its 31P{1H}-NMR spectrum with satellites due to
platinum-195, and the large value of 1J(PtP) of 3773 Hz
is consistent with a phosphorus trans to a methyl group
[15]. Complex 4 slowly decomposed in solution to give
5, together with methane. This is an example of the
well-known cyclometallation reaction [16]. This could
involve an azinelene-hydrazone tautomerism, i.e. a
1,3-proton shift. The equilibrium between the
azinelene forms of organic molecules, containing the
CH2CꢀNꢁN fragment, is well-known [17], and it has
been shown that the presence of a metal fragment and
a specific organic fragment may shift the equilibrium by
imposing coordination to the metal center. In the
1H-NMR data for complex 5, the single plati-
num-methyl resonance, coupled with 195Pt, appears at l
Several points are noteworthy regarding the structure
in 4. The pyridyl group of the ligand in 4 is rotated
away from the phosphorus atom giving an anti configu-
ration. The six-membered ring chelate of the PN ligand
causes a twisted conformation of the ligand. In particu-
lar, the methylene group is puckered, resulting in the
diastereotopic behavior in the 1H-NMR of 4. The
molecular structure of 5 comprises the expected square
planar arrangement of the three donor atoms of PNN
and the methyl ligand around the platinum atom. The
bond angles between Pt and two neighboring donor
atoms lie in the range 85.16(19)–95.3(3)°, the smallest
angles corresponding to the terdentate ligand. The lig-
andꢁpalladium distances are close to those of other
palladium complexes containing five- and six-membered
phosphino-imino chelates [9c]. The most striking fea-
tures of 5 are the configurations around the CꢀN
bonds. The ‘ene’ carbons, C(12) and C(17), are sepa-
2
0.67 with J(PtH)=68.2 Hz. Compared to the complex
,
rated by 1.38(2) A, consistent with a CꢀC double bond.
2
4, the coupling constant J(PtH) is smaller. However,
,
The imine N(11)ꢁC(12) distance (1.36(2) A) is slightly
this value is still within the range expected for a plati-
num(II) complex [18], and the difference may be at-
tributed to the geometric changes during ortho metala-
tion. The methine CHꢀC proton gave a peak at l 4.23
longer than that of 4. A significant change in bond
length is observed for the N(11)ꢁN(10) distance (1.33(2)
A), consistent with an NꢀN double bond. The bond
,
lengths of the ligand indicate that 5 exists in the
azinelene-hydrazone tautomerism, leading to the de-
localization through five atoms, C(17)ꢁC(12)ꢁ
N(11)ꢁN(10)ꢁC(8).
4
ppm with J(PtH)=39.2 Hz. Additionally, 195Pt cou-
plings are present in the 1H-, 13C{1H}- and
31P{1H}-NMR spectra of the platinum compound 5;
the large PtꢁP coupling constant of 3786 Hz, and PtꢁC
coupling constant of 786 Hz on the methyl group of 5
indicate that the methyl resides cis with respect to the
phosphorus. Although all the spectra of 4 and 5 are
consistent with the proposed formulation, the bonding
mode and configuration of 4 and 5 are still unclear.
Accordingly, the monomeric nature for 4 and 5 were
confirmed through a single-crystal X-ray diffraction
analysis.
2.4. Oxidati6e addition to PtMe{PPh2CHC(tBu)-
NNCMe(2-Py)-s3N,N%,P}
The addition of iodomethane to a solution of 5 in
CH2Cl2 at 50–60°C led to the immediate formation of
a dimethylplatinum(IV) complex PtMe2I{PPh2CHC-
(tBu)NNCMe(2-py)-k3N,N%,P} (10) (Eq. (2)). Oxidative
addition of the alkyl halides to platinum(II) substrates

168
C. Lee et al. / Journal of Organometallic Chemistry 587 (1999) 165–175
Table 1
Crystallographic data for 4, 5 and 9
Formula
C
626.6
Monoclinic
P21/n
27H34N3PPt
C26H30N3PPt
610.6
Triclinic
P1
C25H26BrN2PPd
571.8
Monoclinic
P21/c
Formula weight
Crystal system
Space group
,
a (A)
11.693(7)
15.661(19)
14.613(6)
8.808
9.867
11.990(7)
13.132(9)
19.349(11)
,
b (A)
,
c (A)
16.145
103.50
96.69
112.96
1221.9
2
h (°)
i (°)
k (°)
93.018(4)
97.605(5)
3
,
V (A )
2672.0(4)
4
3020.0(3)
4
Z
F(000)
1240
1.558
5.329
0.3×0.2×0.2
ꢀ/2q
600
1.660
5.825
0.4×0.2×0.4
ꢀ/2q
1332
1.454
2.013
0.2×0.2×0.3
ꢀ/2q
Dcalc (g cm−3
)
Absorption coefficient (mm−1
Crystal dimensions (mm)
Scan type
)
Data set (hkl)
q Range (°)
T (K)
−14:14, 0:19, 0:18
1.91–25.97
293
−10:10, −11:11, 0:19
1.33–25.97
293
0:14, 0:16, −23:23
1.71–25.97
293
No. of data collected
No. of unique reflections
No. of parameters refined
Goodness-of-fit
5559
5238
289
0.853
0.036
0.103
4950
4770
280
0.564
0.073
0.164
6237
5909
320
0.910
0.057
0.114
a
R
b
Rw
a R=SꢀꢀFoꢀ−ꢀFcꢀꢀ/SꢀFoꢀ.
b Rw=Sw(ꢀFoꢀ−ꢀFcꢀ)2/SwꢀFoꢀ2]1/2, w=1/[|2(Fc)+0.001(Fo)2].
is well documented and experimental evidence points to
a trans stereochemistry in the resulting platinum com-
pounds [19].
2.5. Synthesis and characterization of complexes from
the ligand 2
The six-membered metallacycle PtMe2{PPh2CH2C-
(tBu)ꢀNꢁNꢀC(H)SC4H3-k2N,P} (7) was prepared by
the reaction of PtMe2(cod) with 2 in toluene (Scheme
(2)
Compound 10 was characterized by NMR spec-
troscopy and elemental analysis. The complex 10 gave
1
two PtMe resonances in the H-NMR spectrum. The
coupling constant 2J(PtH) was 65 Hz for the PtMe
group trans with the iodide and 62 Hz for the PtMe
group trans to the imine nitrogen. As reported for
analogous compounds [20], the methyl trans to the io-
dide appears at higher fields as compared with the
methyl groups trans to the nitrogen atoms and has a
2
somewhat higher value of J(PtH) due to the low trans
influence of the iodide [13]. Our results are consistent
with previous observations. The reduced coupling con-
2
stants J(PtH) for 10 compared to 5 are typical of plat-
inum(IV) compared to platinum(II) [21]. Two resonances
in the 13C-NMR spectrum appear at l 3.6 and −0.9
ppm with platinum satellites (J(PtC)=ca. 730–780 Hz).
1
The small value of J(PtꢁP) (1692 Hz) in the 31P{1H}-
Fig. 1. Molecular structure of PtMe2{PPh2CH2C(tBu)ꢀNꢁNꢀCMe(2-
py)-k2N,P} (4). The thermal ellipsoids are drawn at the 30% level.
NMR spectrum is also typical for platinum(IV) [22].

C. Lee et al. / Journal of Organometallic Chemistry 587 (1999) 165–175
169
t
3
´
Fig. 2. Molecular structure of PtMe{PPh2CH···C( Bu)···N···N···CMe(2-py)-s N,N,P} (5). The thermal ellipsoids are drawn at the 30% level.
Hz, typical of an enamine carbon in a six-membered
ring. This resonance is shifted almost 55 ppm downfield
as compared with the methylene carbon of 7. The
observation of a CH carbon at l 178 coupled with the
phosphorus atom is also consistent with the neutral
structure for 8.
2). The compound 7 is a yellow solid which was charac-
1
terized by H-, 13C- and 31P-NMR spectra and elemen-
tal analysis. In the 1H-NMR spectrum, the resonance of
the methyl group bound to platinum appears as two
doublets at l 0.71 and 0.57 due to coupling with the
phosphorus atom and coupling constant values
(2J(PtH)=ca. 70–90 Hz) are characteristic for a platin-
um(II) compound with the methyl trans to N and P.
The resonance due to the iminic proton is also coupled
with 195Pt(3J(PtH)=ca. 41 Hz), thus showing the coor-
dination of the ligand to platinum through the nitro-
gen. The methylene resonance appears as an AB
quartet. The 13C-NMR spectrum of 7 showed two
separated doublet resonances for the two PtꢁCH3
groups. The value of l 24.3 for the chemical shift of the
methylene carbon is as expected in a six-membered
chelate ring, whereas in a five-membered chelate ring,
a higher value of l ca. 40 is found [15]. The
31P{1H}-NMR spectrum of 7 consisted of a singlet at l
31.6 with satellites due to 195Pt[J(PtP)=2144 Hz].
Treatment of the ligand 2 with PtCl2(cod) in hot
toluene in the presence of triethylamine gave the neu-
tral deprotonated platinum(II) complex 8 in 75% yield.
The initial indication of the mononuclear formulation
for 8 stemmed from the observation of a parent ion in
2.6. Synthesis and characterization of complexes from
ligand 3
The metallacycle [PdBr{PPh2CH2C(tBu)ꢀNꢁNꢀCH-
(C6H4)-k3C,N,P}] (9) was prepared by the reaction of
Pd2(dba)3(dba=dibenzylideneacetone) with the poten-
tially terdentate P,N,C ligand PPh2CH2C(tBu)ꢀNꢁNꢀ
CH(C6H4Br) (3) by oxidative addition of one of the
ortho CꢁBr bonds in toluene (Eq. (3)).
(3)
1
the mass spectrum at m/z 929. In the H-NMR spec-
trum, the PCH proton appeared as a doublet at l 4.17
The resulting yellow product 9 was isolated as a moder-
ately air-sensitive, crystalline solid in high yield. This
compound is readily soluble in benzene, toluene, and
THF. Compound 9 was characterized by its 1H-,
13C- and 31P-NMR spectra, elemental analysis and the
crystal structure determination of 9. The mass spectra of
with a satellite due to coupling to 195Pt(3J(PtH)=48.2
2
Hz) and with J(PH)=8.8 Hz. The values are com-
parable to those observed for the deprotonated six-
membered metal complexes [23]. The 13C{1H}-NMR
1
spectrum shows a doublet at l 79.1 with J(PC)=48.8

170
C. Lee et al. / Journal of Organometallic Chemistry 587 (1999) 165–175
Accordingly, the nature of the metal center for 9 was
confirmed through a single-crystal X-ray diffraction
analysis.
the compounds were also recorded. The iminic proton
resonance was present at l 8.70 with J(PH)=2.8 Hz,
4
and its coupling constant with phosphorus shows a
coordination of the nitrogen atom to the palladium.
The methylene group gives rise to one signal in the
1H-NMR spectrum (l 3.07). The 13C data are also
consistent with the assigned structure. In particular, the
low value of l 21.2 for the methylene carbon is in
agreement with the observed low value of l 24.0 for the
2.7. Description of the molecular structure of 9
A crystal of 9 suitable for an X-ray diffraction study
was grown from hexane at −15°C. A summary of the
data collection and crystallographic parameters for 9 is
given in Table 1. The relevant bond lengths and angles
are shown in Table 2. The crystal structure is composed
of discrete molecules separated by van der Waals dis-
tances. The molecular structure of 9 is given in Fig. 2.
The molecule contains one PdC3N five-membered ring
and one PdN2C2P six-membered ring. The palladium
six-membered
[Mo(CO)4(PPh2CH2C(tBu)ꢀNNMe2)]
complex [24]. This value is comparable to those of 6. In
the IR spectrum of 9, the peaks at 1615 and 1574 cm−1
are assigned to the stretching mode of w(CꢀN). Al-
though all the spectra are consistent with the proposed
formulation, the bonding mode in 9 is still unclear.
Table 2
,
Selected bond lengths (A) and bond angles (°) for 4, 5 and 9
Bond lengths
Compound 4
Pt(1)ꢁC(30)
Pt(1)ꢁP(17)
N(10)ꢁC(11)
2.061(10)
2.249(2)
1.269(11)
Pt(1)ꢁC(31)
C(7)ꢁN(9)
C(11)ꢁC(16)
2.088(10)
1.293(11)
1.498(11)
Pt(1)ꢁN(9)
N(9)ꢁN(10)
C(16)ꢁP(17)
2.123(7)
1.413(9)
1.876(7)
Compound 5
Pt(1)ꢁN(2)
Pt(1)ꢁP(18)
C(8)ꢁN(10)
C(12)ꢁC(17)
2.053(17)
2.175(5)
1.36(2)
Pt(1)ꢁC(31)
N(2)ꢁC(7)
N(10)ꢁN(11)
C(17)ꢁP(18)
2.10(2)
1.37(2)
1.33(2)
1.78(2)
Pt(1)ꢁN(10)
C(7)ꢁC(8)
N(11)ꢁC(12)
2.127(14)
1.37(3)
1.36(2)
1.38(2)
Compound 9
Pd(1)ꢁC(1)
Pd(1)ꢁBr
N(1)ꢁN(2)
C(6)ꢁC(7)
2.044(8)
2.424(11)
1.402(9)
1.449(11)
Pd(1)ꢁN(1)
PꢁC(13)
N(2)ꢁC(8)
C(8)ꢁC(13)
2.054(6)
1.835(8)
1.276(10)
1.510(11)
Pd(1)ꢁP
N(1)ꢁC(7)
C(1)ꢁC(6)
2.318(2)
1.298(10)
1.391(11)
Bond angles
Compound 4
C(30)ꢁPt(1)ꢁC(31)
C(31)ꢁPt(1)ꢁN(9)
N(9)ꢁPt(1)ꢁP(17)
N(10)ꢁN(9)ꢁPt(1)
N(10)ꢁC(11)ꢁC(16)
C(24)ꢁP(17)ꢁC(16)
C(16)ꢁP(17)ꢁPt(1)
86.7(4)
92.9(3)
C(30)ꢁPt(1)ꢁN(9)
C(30)ꢁPt(1)ꢁP(17)
C(7)ꢁN(9)ꢁPt(1)
C(11)ꢁN(10)ꢁN(9)
C(11)ꢁN(10)ꢁN(9)
C(18)ꢁP(17)ꢁPt(1)
179.3(4)
95.3(3)
130.5(6)
116.0(7)
111.7(5)
119.0(3)
85.16(19)
114.2(5)
124.7(7)
101.0(3)
109.1(3)
Compound 5
N(2)ꢁPt(1)ꢁC(31)
C(31)ꢁPt(1)ꢁN(10)
C(31)ꢁPt(1)ꢁP(18)
N(2)ꢁC(7)ꢁC(8)
N(11)ꢁN(10)ꢁC(8)
C(8)ꢁN(10)ꢁPt(1)
N(11)ꢁC(12)ꢁC(17)
91.7(9)
171.4(9)
94.0(7)
117.9(17)
119.8(16)
109.8(13)
131.9(19)
N(2)ꢁPt(1)ꢁN(10)
N(2)ꢁPt(1)ꢁP(18)
N(10)ꢁPt(1)ꢁP(18)
N(10)ꢁC(8)ꢁC(7)
N(11)ꢁN(10)ꢁPt(1)
N(10)ꢁN(11)ꢁC(12)
79.9(7)
174.3(6)
94.4(5)
119.4(18)
130.5(12)
124.6(16)
Compound 9
C(1)ꢁPd(1)ꢁN(1)
N(1)ꢁPd(1)ꢁP
81.3(3)
C(1)ꢁPd(1)ꢁP
C(1)ꢁPd(1)ꢁBr
PꢁPd(1)ꢁBr
C(7)ꢁN(1)ꢁN(2)
N(2)ꢁN(1)ꢁPd(1)
C(6)ꢁC(1)ꢁPd(1)
N(1)ꢁC(7)ꢁC(6)
169.6(2)
93.1(2)
89.88(18)
170.07(18)
103.4(3)
113.4(5)
120.2(7)
116.0(7)
126.0(7)
N(1)ꢁPd(1)ꢁBr
C(13)ꢁPꢁPd(1)
C(7)ꢁN(1)ꢁPd(1)
C(8)ꢁN(2)ꢁN(1)
C(1)ꢁC(6)ꢁC(7)
N(2)ꢁC(8)ꢁC(13)
96.42(6)
110.8(6)
134.7(5)
111.3(6)
117.9(8)

C. Lee et al. / Journal of Organometallic Chemistry 587 (1999) 165–175
171
Scheme 2.
atom is in a slightly distorted square-planar environ-
ment, coordinated to carbon, bromine, nitrogen, and
the phosphorus atoms. The metallacycle is approxi-
mately planar; the largest deviation from the mean
six-membered palladacycle [PdBr{PPh2-CH2C(tBu)ꢀ
NꢁNꢀCHC6H4-k3C,N,P}] was prepared by the reaction
of Pd2(dba)3 with the potentially terdentate PNC ligand
PPh2CH2C(tBu)ꢀNꢁNꢀCH(o-BrC6H4) by oxidative ad-
dition of the ortho CꢁBr bond. However, the reaction
of Ni(cod)2 or Pt(cod)2 led to intractable products. The
stability and isolation of the palladium complex 9 may
have catalytic applications. We are currently in the
process of using this complex to synthesize allylic alky-
lation reactions.
,
plane determined by the five atoms is 0.0135 A for
N(1). The angles between adjacent atoms in the coordi-
nation sphere lie in the range 96.42(6) (PꢁPdꢁBr) to
81.3(3)° (C(1)ꢁPdꢁN(1)), the smallest angles corre-
sponding to the terdentate ligand. The distances be-
tween the palladium and the coordinated atoms are
well within the range of values obtained for other
analogous compounds [25].
4. Experimental
3. Conclusions
4.1. General procedures
We have shown that the potentially terdentate lig-
ands 1, 2, and 3 can coordinate to palladium and
platinum in bi- and terdentate coordination modes. The
reaction of 1 with [Pt2Me4(m-SMe2)2] or PtMe2(cod)
gave the unstable six-membered metallacycle [PtMe2-
{PPh2CH2C(tBu)ꢀNNꢀCMe(2-py)-k2P,N}] which was
slowly converted into the cyclization product [PtMe-
{PPh2CHC(CtBu)NNCMe(2-py)-k3N,N%,P}] (5). Ac-
cordingly, 1 stabilizes a series of organoplatinum com-
plexes with a strong tendency to terdentate coordina-
tion. Oxidative addition of methyl iodide to 5 led to the
immediate formation of a Pt(IV) complex. However,
carbonylation of 5 under 23 bar of CO at r.t. proceeds
very slowly. The six-membered metallacycle PtMe2-
{PPh2CHC(tBu)NNC(H)SC4H3-k2N,P} (7) was pre-
pared by the reaction of PtMe2(cod) with 2. The pro-
longed heating 7 led to decomposition rather than the
cycloplatination product with a PNS coordination fash-
ion. Therefore, bidentate coordination is preferred in
the platinum compound with the ligand 2. The five- and
All manipulations were performed under a dry, oxy-
gen-free, dinitrogen or argon atmosphere using stan-
dard Schlenk techniques or in a Vacuum Atmosphere
HE-493 dry box. Toluene and hexane were freshly
distilled over sodium benzophenone prior to use. All
1H-, 13C- and 31P-NMR spectra were recorded on a
Gemini 200 spectrometer operating at 200.1, 50.3, and
80.9 MHz, respectively. Chemical shifts were referenced
relative to either TMS (1H) or benzene-d6 (1H, l 7.156;
13C{1H}, l 128.00), while 31P-NMR spectra were refer-
enced relative to 85% phosphoric acid. IR spectra were
recorded on a Biorad FTS-165 spectrometer. Mass
spectra were recorded on a high-resolution VG 70-
VSEG instrument and elemental analyses were per-
formed with a Carlo Erba Instruments CHNS-O EA
1108 analyzer. The ligand Z-Ph2PCH2C(tBu)ꢀNNH2
was prepared according to the literature method.
[Me2PtSMe2]2 [26] and Pt(cod)2 [27] were prepared by
published methods. K2PtCl4, MeC(O)tBu, and Pd2-
(dba)3 were used as received from Strem Chemicals.

172
C. Lee et al. / Journal of Organometallic Chemistry 587 (1999) 165–175
4.1.1. PPh2CH2C(tBu)ꢀNꢁNꢀC(Me)NC5H4 (1)
toluene solution of PPh2CH2C(tBu)ꢀNꢁNꢀCMe(py) (2)
(0.140 g, 0.348 mmol) dropwise at −20°C. The solu-
tion was warmed to r.t., and the solution was stirred for
1 h. The solvent was removed in vacuo. The resulting
residue was recrystallized by dissolving in toluene (6 ml)
and placing a layer of hexane, and greenish–yellow
crystals were obtained in 35% yield.
A mixture of phosphino hydrazone L (1.0 g, 3.35
mmol) and 2-acetylpyridine (0.375 ml, 3.35 mmol) was
refluxed in benzene (10 ml) for 1.5 h. The solution was
evaporated to dryness under reduced pressure. The
solids were washed with cold methanol. The crude solid
was crystallized by dissolving in methanol and placing a
layer of hexane above it in a Schlenk tube, and white
crystals were obtained in 52% yield. M.p. 68–70°C.
1H-NMR (CDCl3): l 8.62 (d, 1H, JHH=3.48 Hz,
Method (ii). Compound 4 was also prepared accord-
ing to Method (i), except that PtMe2(cod) was used
instead of [PtMe2(m-SMe2)]2 in 80% yield. M.p. 159–
1
NC5H4), 7.82 (d, 1H,
J
HH=5.44 Hz, NC5H4),
161°C. H-NMR (C6D6): l 8.68 (d, 1H, J(HH)=7.6
7.58–7.05 (m, 12H, pyridyl and phenyl groups), 3.10 (d,
2H, JHꢁP=3.60 Hz, CH2), 2.22 (s, 3H, CH3), 1.22 (s,
9H, CMe3). 13C{1H}-NMR (CDCl3): l 168.55 (s, 1C,
CꢀN), 155.52 (s, 1C, CꢀN), 146.17, 139.11, 136.77,
135.62, 133.05, 131.16, 128.53, 123.44, 121.08, 38.87 (s,
1C, CMe3), 29.25 (s, 3C, CMe), 28.42 (d, 1C, J(PC)=
26.1 Hz, CH2), 13.77 (s, 1C, CH3). 31P{1H}-NMR
(CDCl3): l −10.78. IR (KBr pellet, cm−1): 1652
(w(CꢀN)), 1616 (w(CꢀN)).
Hz, CH), 7.57 (d, 1H, J(HH)=3.2 Hz, CH), 7.92–7.24
2
(m, 12H, Ph and pyridyl), 3.55 (dd, 1H, J(PH)=2.1,
2
3J(PtH)=21.6 Hz, CH2P), 2.51 (dd, 1H, J(PH)=2.1,
3J(PtH)=21.6 Hz, CH2P), 2.30 (s, 3H, CH3), 0.88 (s,
t
3
2
9H, Bu), 0.62 (d, 3H, J(PH)=7.6, J(PtH)=90.4 Hz,
3
2
PtꢁCH3), −0.06 (d, 3H, J(PH)=8.1, J(PtH)=69.6
Hz, PtꢁCH3). 13C{1H}-NMR (CDCl3): l 181.64 (s, 1C,
CꢀN), 170.10 (s, 1C, CꢀN), 148.37, 135.05, 134.76,
132.81, 132.01, 131.78, 130.80, 130.07, 128.78, 128.60,
128.22, 128.01, 30.50 (s, 1C, CMe3), 27.51 (s, 3C,
4.1.2. PPh2CH2C(tBu)ꢀNꢁNꢀC(H)SC4H3 (2)
CMe3), 24.99 (d, 1C, J(PC)=8.48 Hz, CH2) 7.62 (d,
1
2
1
A mixture of phosphino hydrazone L (0.67 g, 2.25
mmol) and 2-thiophenecarbaldehyde (0.22 ml, 2.25
mmol) was refluxed in benzene (5 ml) for 3 h. The
solvents were removed in vacuo. The yellow powders
were washed with cold MeOH. Recrystallization from a
solution of MeOH layered by hexane produced crystals
1C, J(PC)=16.8, J(PtC)=778 Hz, PtꢁCH3), 1.22 (d,
1C, 2J(PC)=11.7, 1J(PtC)=748 Hz, PtꢁCH3).
31P{1H}-NMR (CDCl3): l −1.31 (d, J(PtP)=3772.7
Hz). IR (KBr pellet, cm−1): 1604, 1587 (w(CꢀN)). MS
(EI): m/z 626 [M+]. Anal. Calc. for C27H34N3PPt: C,
51.71; H, 5.43. Found: C, 51.22; H, 5.21%.
1
in 55% yield. M.p. 82–84°C. H-NMR (CDCl3): l 8.20
(s, 1H, CH), 7.58–6.95 (m, 13H, Ph and SC4H3), 3.58
(d, 2H, J(PH)=2.64 Hz, CH2), 1.24 (s, 9H, CMe3).
13C{1H}-NMR (CDCl3): l 175.71 (s, 1C, CꢀN), 155.78
(s, 1C, CꢀN), 151.31, 140.02, 139.04, 133.36, 132.95,
130.95, 129.05, 128.66, 127.23, 38.52 (s, 1C, CMe3),
29.33 (d, 1C, J(PC)=31.2 Hz, CH2), 28.74 (s, 3C,
CMe3). 31P{1H}-NMR (CDCl3): l −8.16. IR (KBr
pellet, cm−1): 1606.9 (w(CꢀN)).
4.1.5. PtMe{PPh2CH ···C(tBu) ···N ···N ···CMe(2-py)-
s3N,N%,P} (5)
PPh2CH2C(tBu)ꢀNꢁNꢀCMe(py) (2) (0.140 g, 0.348
mmol) was added to a solution of [PtMe2(m-SMe2)]2
(0.100 g, 0.174 mmol) in 10 ml of toluene, and this
mixture was heated at 55°C for 2 h. The solvent and the
liberated SMe2 were removed under vacuum, and the
resulting oily blue solid was washed with pentane to
give a blue solid. The crude solid was recrystallized by
dissolving in toluene and placing a layer of hexane
above it, and deep blue crystals were obtained in 45%
yield. M.p. 132–136°C (dec.). 1H-NMR (C6D6):
l 7.82–6.86 (m, 14H, Ph and pyridyl), 4.23 (d, 1H,
2J(HP)=2.4, 3J(HPt)=39.2 Hz, CH), 2.17 (s, 3H,
4.1.3. PPh2CH2C(tBu)ꢀNꢁNꢀC(H)Q (Q=2-bromo-
benzyl) (3)
Compound 3 was prepared according to the same
method used for 2, except that 2-bromobenzaldehyde
was used instead of 2-acetylpyridine. Yield: 54%. M.p.
88–90°C. 1H-NMR (CDCl3): l 8.36 (s, 1H, CH), 7.65–
7.04 (m, 14H, Ph and NC5H4), 3.51 (d, 2H, J(PH)=2.4
Hz, CH2), 1.27 (s, 9H, CMe3). 13C{1H}-NMR (CDCl3):
l 175.92 (s, 1C, CꢀN), 155.74 (s, 1C, CꢀN), 139.05,
138.71, 133.16, 132.90, 132.76, 131.25, 128.69, 127.10,
125.17, 38.72 (s, 1C, CMe3), 29.14 (s, 3C, CMe3), 28.66
(d, 1C, J(PC)=22.6 Hz). IR (KBr pellet, cm−1):
1607.2 (w(CꢀN)).
t
CH3), 1.26 (s, 9H, Bu), 0.67 (d, 3H, 3J(HP)=3.1,
2J(HPt)=49.6 Hz, CH3). 13C{1H}-NMR (CDCl3): l
182.4 (d, 1C, 2J(PC)=18.8 Hz, CꢀN), 158.2 (s, 1C,
2J(PtC)=35.6 Hz, CꢀN), 144.5, 142.8, 138.8, 136.7,
133.00, 132.8, 129.8, 128.2, 121.4, 77.4 (d, 1C, 1J(PC)=
51.2 Hz, CHP), 38.8 (s, 1C, CMe3), 30.5 (s, 3C, CMe3),
22.6 (s, 1C, CH3), −0.68 (d, 1C, 2J(PC)=12.8,
1J(PtC)=786 Hz, PtꢁCH3). 31P{1H}-NMR (C6D6): l
−1.31 (d, J(PtP)=3786.1 Hz). IR (KBr pellet, cm−1):
1593 (w(CꢀN)). MS (EI): m/z 611 [M+]. Anal. Calc. for
C26H30N3PPt: C, 51.11; H, 4.91. Found: C, 50.84; H,
4.82%.
4.1.4. PtMe2{PPh2CH2C(tBu)ꢀNꢁNꢀCMe(2-py)-
s2N,P} (4)
Method (i). To a stirred toluene (10 ml) solution of
[PtMe2(m-SMe2)]2 (0.100 g, 0.174 mmol) was added a

C. Lee et al. / Journal of Organometallic Chemistry 587 (1999) 165–175
173
4.1.6. Oxidati6e addition reaction
and 10 ml of toluene. The reaction mixture was stirred
at r.t. for 1 h. The volume was reduced to ca. 4 ml and
the solution was layered with hexane (4 ml). The yellow
product was filtered and dried in vacuo, yielding 94 mg
To a stirred solution of 5 (0.035 g, 0.057 mmol) in
dichloromethane (5 ml) was added MeI (0.15 ml). The
solution was heated to 50–60°C. After 4 h the violet
solution was evaporated to dryness. The product was
extracted with toluene (6 ml). The volume was reduced
to ca. 3 ml and the product layered with hexane (4 ml)
and the violet product was filtered. The product was
dried in vacuo, yielding 35 mg of a violet product
1
of a yellow product (85%). M.p. 202–204°C. H-NMR
4
3
(CDCl3): l 8.66 (d, 1H, J(PH)=2.2 Hz, J(PtH)=
40.8 Hz, CH), 7.83–6.94 (m, 13H, Ph and thiophene),
3.44 (dd, 1H, 2J(PH)=2.2 Hz, 3J(PtH)=23.8 Hz,
2
3
CH2P), 2.49 (dd, 1H, J(PH)=1.6 Hz, J(PtH)=22.4
1
t
3
(82%). M.p. 143°C (dec.). H-NMR (CDCl3): l 8.08–
Hz, CH2P), 0.86 (s, 9H, Bu), 0.71 (d, 3H, J(PH)=7.4
Hz, 2J(PtH)=91.2 Hz, PtꢁCH3), 0.57 (d, 3H,
3J(PH)=7.6 Hz, 2J(PtH)=70.2 Hz, PtꢁCH3).
13C{1H}-NMR (CDCl3): l 178.4 (s, 1C, CꢀN), 174.3 (s,
1C, CꢀN), 147.1, 134.9, 134.7, 132.2, 131.9, 130.7,
129.8, 128.5, 128.2, 126.4, 38.9 (s, 1C, CMe3). 27.3
2
7.17 (m, 14H, Ph and Py), 4.28 (d, 1H, J(HP)=4.8,
3J(HPt)=30.8 Hz, CH), 2.54 (s, 3H, CH3), 1.48 (d, 3H,
3J(HP)=1.5, 2J(PtH=61.53 Hz, CH3), 1.36 (s, 9H,
tBu), 0.58 (d, 3H, 3J(HP)=3.4, 2J(HPt)=64.84 Hz,
CH3). 13C{1H}-NMR (CDCl3):
l 183.9 (d, 1C,
2J(PC)=16.6 Hz, CꢀN), 160.3 (s, 1C, J(PtC)=33.8
Hz, CꢀN), 148.6, 145.3, 142.2, 137.2, 134.7, 133.6,
129.2, 128.6, 123.2, 76.8 (d, 1C, 1J(PC)=48.4 Hz,
CHP), 39.4 (s, 1C, CMe3), 29.2 (s, 3C, CMe3), 23.4 (s,
(s, 3C, CMe3), 24.3 (d, 1C, J(PC)=8.9 Hz, CH2), 7.9
2
1
2
1
(d, 1C, J(PC)=14.4 Hz, J(PtC)=788 Hz, PtꢁCH3),
−0.8 (d, 1C, 2J(PC)=10.8 Hz, 1J(PtC)=754 Hz,
PtꢁCH3). 31P{1H}-NMR (CDCl3): l 31.6 (s, J(PtP)=
2143.7 Hz). IR (KBr pellet, cm−1): 1602, 1585
(w(CꢀN)). Anal. Calc. for C25H31N2PSPt: C, 48.48; H,
5.01. Found: C, 48.73; H, 5.26%.
2
1
1C, CH3), 3.6 (d, 1C, J(PC)=11.6, J(PtC)=734 Hz,
PtꢁCH3), −0.9 (d, 1C, 2J(PC)=12.2, 1J(PtC)=778
Hz, PtꢁCH3). 31P{1H}-NMR (CDCl3): l −12.84 (d,
J(PtP)=1691.8 Hz). Anal. Calc. for C27H33IN3PPt: C,
43.06; H, 4.39. Found: C, 43.46; H, 4.51%.
4.1.9. Pt{PPh2CHꢀC(tBu)-NꢁNꢀC(H)SC4H3-s2N,P}2
(8)
4.1.7. PtCl{PPh2CH ···C(tBu) ···N ···N ···CMe(2-py)-
s3N,N%,P} (6)
A 100 ml Schlenk tube was charged with 0.2 g (0.51
mmol) of PPh2CH2C(tBu)ꢀNꢁNꢀC(H)SC4H3, 0.19 g
(0.51 mmol) of PtCl2(cod), and 15 ml of toluene. The
reaction mixture was stirred at r.t. for 0.5 h, and 0.17
ml of NEt3 was added. This mixture was heated at 60°C
for 2 h. The white precipitate was removed by filtration,
and the solvent was removed by vacuum. The purifica-
tion was achieved by preparative TLC using a solvent
mixture of CH2Cl2 and diethyl ether (20:1). An analyti-
cal sample of the new compound was obtained by
recrystallization from a 2:1 mixture of CH2Cl2 and
hexane in 75% yield. M.p. 156–158°C. 1H-NMR
(CDCl3): l 8.20 (s, 1H, CH), 7.62–6.64 (m, 13H, Ph
and thiophene), 4.17 (d, 1H, 2J(PH)=8.8 Hz,
PPh2CH2C(tBu)ꢀNꢁNꢀCMe(py) (2) (0.1 g, 0.25
mmol) and PtCl2(cod) (0.093 g, 0.25 mmol) were put
into a 100 ml Schlenk flask. This flask was evacuated
and refilled with dinitrogen before 10 ml of toluene and
0.2 ml of NEt3 were added to the flask via syringe with
stirring. The mixture was refluxed for 3 h, and the
solvent was removed in vacuo. The resulting blue solid
was extracted with toluene and filtered through a 2 cm
filter of Celite, and the toluene was removed under
vacuum. Recrystallization from a solution of toluene
layered with hexane gave rise to deep blue crystals in
1
68% yield. M.p. 156–158°C. H-NMR (CDCl3): l 8.92
t
(d, 1H, J(HH)=6.8 Hz, CH), 7.84–7.12 (m, 13H, Ph
and py), 3.99 (d, 1H, J(PH)=4.4, J(PtH)=11.4 Hz,
CHP), 2.26 (s, 3H, J(PtH)=9.6 Hz, CꢁCH3), 1.27 (s,
9H, tBu). 13C{1H}-NMR (CDCl3): l 184.8 (d, 1C,
3J(PtH)=48.2 Hz, CHP), 1.44 (s, 9H, Bu). 13C{1H}-
2
NMR (CDCl3): 178.4 (d, 1C, J(PC)=6.4 Hz, CꢁN),
154.7 (s, 1C, CꢀN), 144.3; 132.8, 132.7, 132.4, 130.4,
129.7, 128.8, 127.9, 126.5, 123.7, 123.0, 79.1 (d, 1C,
1J(PC)=48.8 Hz, CHP), 37.7 (s, 1C, CMe3), 30.9
2J(PC)=18.2 Hz, CꢁN), 161.6 (s, 1C, J(PtC)=37.1
2
Hz, CꢀN), 147.3, 144.6, 139.6, 138.2, 133.3, 133.1,
130.3, 128.3, 118.9, 79.2 (d, 1C, 1J(PC)=54.2 Hz,
CHP), 38.4 (s, 1C, CMe3), 30.35 (s, 3C, CMe3), 19.3
(s, 1C, CCH3). 31P{1H}-NMR (C6D6): l −9.22
(d, J(PtP)=3668.7 Hz). IR (KBr pellet, cm−1): 1592
(w(CꢀN)). Anal. Calc. for C25H27ClN3PPt: C, 47.61; H,
4.28. Found: C, 47.33; H, 4.12%.
(s, 3C, CMe3). 31P{1H}-NMR (CDCl3):
l 22.5
(d, J(PtP)=3155.2 Hz). IR (KBr pellet, cm−1): 1570
(w(CꢀN)). MS (EI): m/z 929 [M+]. Anal. Calc. for
C42H48N4P2S2Pt: C, 54.25; H, 5.17. Found: C, 54.03; H,
5.02%.
4.1.10. PdBr{PPh2CH2C(tBu)ꢀNꢁNꢀCH(C6H4)-
s3C,N,P} (9)
To a solution of Pd2(dba)3 (0.197 g, 0.22 mmol) in
CH2Cl2 (5 ml) was added a solution of PPh2CH2-
C(tBu)ꢀNꢁNꢀCH(C6H4Br) (3) (0.2 g, 0.43 mmol)
in CH2Cl2 (5 ml) with stirring. The mixture was
4.1.8. PtMe2{PPh2CH2C(tBu)ꢀNꢁNꢀC(H)SC4H3-
s2N,P} (7)
A 100 ml Schlenk tube was charged with 0.07 g
(0.178 mmol) of 2, 0.067 g (0.195 mmol) of PtMe2(cod),

174
C. Lee et al. / Journal of Organometallic Chemistry 587 (1999) 165–175
Fig. 3. Molecular structure of PdBr{PPh2CH2C(tBu)ꢀNꢁNꢀCH(C6H4)-k3C,N,P} (9). The thermal ellipsoids are drawn at the 30% level.
,
refluxed for 1 h, and the solvent was removed in
vacuum. The yellow residue was extracted with hexane
(15 ml). The solution was reduced to small volume and
after cooling to −15°C overnight, yellow microcrystals
were obtained in 42% yield. M.p. 108–110°C. 1H-NMR
(CDCl3): l 8.70 (d, 1H, 4J(PH)=2.8 Hz, CH),
7.82–7.02 (m, 14H, Ph), 3.07 (d, 2H, J(PH)=10.2 Hz,
mated diffractometer. Mo–Ka radiation (u=0.7107 A)
was used for all structures. Each structure was solved
by the application of direct methods using the SHELXL
86 program and least-squares refinement using SHELXL
-
-
93. Non-hydrogen atoms of 4, 5, and
9 were
anisotropically refined, and hydrogen atoms were
isotropically refined. The hydrogen atoms were in-
cluded as constant contributions to the structure fac-
tors. Selected bond distances and angles for 4, 5, and
9 are given in Table 2. The molecular structure of
compounds 4, 5, and 9 are given in Figs. 1–3, respec-
tively.
t
CH2P), 0.85 (s, 9H, Bu). 13C{1H}-NMR (CDCl3): l
179.1 (d, 1C, 2J(PC)=4.15 Hz, CꢀN), 171.2 (s, 1C,
CꢀN), 142.4, 136.2, 133.9, 132.3, 131.2, 130.2, 129.5,
128.9, 128.7, 125.6, 40.7 (s, 1C, CMe3), 27.3 (s, 3C,
CMe3), 21.2 (d, 1C, 1J(PC)=13.7 Hz, CH2P).
31P{1H}-NMR (CDCl3): l 18.13. IR (KBr pellet,
cm−1): 1615, 1574 (w(CꢀN)). Anal. Calc. for
C25H26N2PBrPd: C, 52.52; H, 4.58. Found: C, 52.21; H,
4.42%.
5. Supplementary material
Tables of bond distances and angles, atomic coordi-
nates, fractional coordinates for hydrogen atom, ther-
mal parameters, and X-ray data for 4, 5, and 9 (24
pages) are available. Ordering information is given on
any current masthead page.
4.2. X-ray crystallography
Details of the crystal data and a summary of inten-
sity data collection parameters for 4, 5, and 9 are given
in Table 1. The crystals of 4 and 5 were grown from a
toluene–hexane solution at −15°C. The crystal of 9
was grown from hexane solutions stored at −20°C.
The crystals of 4, 5, and 9 were mounted in thin-wall
glass capillaries and sealed under argon. The data sets
4, 5, and 9 were collected on an Enraf CAD4 auto-
Acknowledgements
We appreciate the financial support of the Basic
Science Research Institute Program, Ministry of Educa-
tion 1998, Project no. 3426.

C. Lee et al. / Journal of Organometallic Chemistry 587 (1999) 165–175
175
[10] K.K. Hii, S.D. Perera, B.L. Shaw, M. Thornton-Pett, J. Chem.
Soc. Dalton Trans. (1992) 2361.
References
[11] (a) S.D. Perera, B.L. Shaw, M. Thornton-Pett, J. Chem. Soc.
Dalton Trans. (1991) 1183. (b) S.D. Perera, B.L. Shaw, M.
Thornton-Pett, J. Chem. Soc. Dalton Trans. (1994) 713. (c) S.D.
Perera, B.L. Shaw, J. Chem. Soc. Chem. Commun. (1994) 1201.
(d) S.D. Perera, B.L. Shaw, M. Thornton-Pett, J. Chem. Soc.
Dalton Trans. (1992) 999. (e) S.D. Perera, B.L. Shaw, M.
Thornton-Pett, J. Organomet. Chem. 428 (1992) 59.
[12] (a) D. You, S.O. Kang, J. Ko, M. Choi, Bull. Kor. Chem. Soc.
18 (1997) 305. (b) C. Paek, S.O. Kang, J. Ko, P.J. Carroll,
Organometallics 16 (1997) 2110. (c) C. Paek, S.O. Kang, J. Ko,
P.J. Carroll, Organometallics 16 (1997) 1503.
[13] (a) M. Crespo, Polyhedron 15 (1996) 1981. (b) P.K. Monaghan,
R.J. Puddephatt, Organometallics 4 (1985) 1406. (c) C.R. Baar,
H.A. Jenkins, J.J. Bittal, G.P.A. Yap, R.J. Puddephatt, G.
Ferguson, A.J. Lough, J. Chem. Soc. Chem. Commun. (1989)
1297.
[1] (a) I. Omae, Chem. Rev. 79 (1979) 287. (b) I. Omae, Coord.
Chem. Rev. 83 (1988) 137.
[2] (a) J. Albert, A. Gonzalez, J. Granell, R. Moragas, C. Puerta,
P. Valerga, Organometallics 16 (1977) 3775. (b) G. van Koten,
Pure Appl. Chem. 61 (1989) 1681. (c) P.L. Alsters, P.F. Engel,
M.P. Hogerheide, M. Copijn, A.L. Spek, G. van Koten,
Organometallics 12 (1993) 1831. (d) C. Chan, D.M.P. Mingos,
A.J.P. White, D.J. Williams, J. Chem. Soc. Chem. Commun.
(1996) 81. (e) H. Kraatz, D. Milstein, J. Organomet. Chem. 488
(1995) 223.
[3] (a) P. Wehman, L. Borst, P.C.J. Kamer, P.W.N.M. van
Leeuwen, J. Chem. Soc. Chem. Commun. (1996) 217 (b) R. van
Asselt, C.J. Elsevier, Organometallics 11 (1992) 1999. (c) P.
Wehman, G.C. Dol, E.R. Moorman, P.C.J. Kamer, P.W.N.M.
van Leeuwen, J. Fraanje, K. Goubitz, Organometallics 13 (1994)
4856.
[14] J.D. Ruddick, B.L. Shaw, J. Chem. Soc. A (1969) 2801.
[15] K.K. Hii, S.D. Perera, B.L. Shaw, M. Thornton-Pett, J. Chem.
Soc. Dalton Trans. (1994) 103.
[4] B. Jedlicka, C. Kratky, W. Weissensteiner, M.J. Widhalm,
Chem. Soc. Chem. Commun. (1993) 1329
[5] (a) B.M. Trost, T.R. Verhoeven, J. Am. Chem. Soc. 100 (1978)
3435. (b) P. von Matt, A. Pfaltz, Angew. Chem. Int. Ed. Engl. 32
(1993) 566. (c) J. Sprinz, G. Helmchen, Tetrahedron Lett. 34
(1993) 1769. (d) J. Sprinz, M. Kiefer, G. Helmchen, M. Reggelin,
G. Huttner, O. Walter, L. Zsolnai, Tetrahedron Lett. 35 (1994)
1523.
[6] (a) R.E. Rulke, V.E. Kaasjager, P. Wehman, C.J. Elsevier,
P.W.N.M. van Leeuwen, K. Vrieze, J. Fraanje, K. Goubitz, A.L.
Spek, Organometallics 15 (1996) 3022. (b) P. Wehman, R.E.
Rulke, V.E. Kaasjager, C.J. Elsevier, H. Kooijman, A.L. Spek,
K. Vrieze, R.W.N.M. van Leeuwen, J. Chem. Soc. Chem. Com-
mun. (1995) 331. (c) T.B. Rauchfuss, P.A. Tucker, Inorg. Chem.
19 (1980) 3306.
[7] (a) D. Hedden, D.M. Roundhill, W.C. Fultz, A.L. Rheingold,
Organometallics 5 (1986) 336. (b) D. Hedden, D.M. Roundhill,
Inorg. Chem. 24 (1985) 4152.
[8] (a) C.R. Sinha, D. Bandyopadhyay, A. Chakravorty, J. Chem.
Soc. Chem. Commun. (1988) 468. (b) T. Kawamoto, L. Na-
gasaw, H. Kuma, Y. Kushi, Inorg. Chem. 35 (1996) 2427. (c) S.
Chattopadhyay, C. Sinha, P. Basu, A. Chakravorty,
Organometallics 10 (1991) 1135. (d) A.K. Mahapatra, D. Bandy-
opadhyay, P. Bandyopadhyay, A. Chakravorty, Inorg. Chem. 25
(1986) 2214
[16] (a) A.D. Ryabov, Chem. Rev. 90 (1990) 403. (b) J.Y. Saillard, R.
Hoffmann, J. Am. Chem. Soc. 106 (1984) 2006.
[17] S.D. Perera, B.L. Shaw, J. Chem. Soc. Chem. Commun. (1995)
865.
[18] (a) C.M. Anderson, M. Crespo, M.C. Jennings, A.J. Lough, G.
Ferguson, R.J. Puddephatt, Organometallics 10 (1991) 2672. (b)
C.M. Anderson, M. Crespo, G. Ferguson, A.J. Lough, R.J.
Puddephatt, Organometallics 11 (1992) 1177.
[19] (a) J.D. Scott, R.J. Puddephatt, Organometallics 5 (1986) 1538.
(b) M. Crespo, R.J. Puddephatt, Organometallics 6 (1987) 2548.
[20] D. Lopez, M. Crespo, M. Font-Bardia, X. Solans, Organometal-
lics 16 (1997) 1233.
[21] (a) J.D. Scott, R.J. Puddephatt, Organometallics 2 (1983) 1643.
(b) C.M. Anderson, R.J. Puddephatt, G. Ferguson, A.J. Lough,
J. Chem. Soc. Chem. Commun. (1989) 1297.
[22] J.D. Kennedy, W. McFarlane, R.J. Puddephatt, P.J. Thompson,
J. Chem. Soc. Dalton Trans. (1976) 874.
[23] S.D. Perera, B.L. Shaw, M. Thornton-Pett, J. Chem. Soc. Dal-
ton Trans. (1993) 3653.
[24] S.D. Perera, B.L. Shaw, M. Thornton-Pett, J. Organomet.
Chem. 428 (1992) 59.
[25] (a) A.M. Aarif, F. Esfevan, A. Garcia-Bernabe, P. Lahuerta, M.
Sanau, M.A. Vbeda, Inorg. Chem. 36 (1997) 6472. (b) H.
Mimoun, R. Charpentier, A. Mitschler, J. Fischer, R. Weiss, J.
Am. Chem. Soc. 103 (1980) 1047. (c) C. King, D.M. Roundhill,
F.R. Fronczek, Inorg. Chem. 26 (1987) 4288.
[9] (a) S.D. Perera, B.L. Shaw, M. Thornton-Pett, J. Chem. Soc.
Dalton Trans. (1992) 1469. (b) S.D. Perera, B.L. Shaw, M.
Thornton-Pett, J. Chem. Soc. Dalton Trans. (1993) 3653. (c)
S.D. Perera, B.L. Shaw, M. Thornton-Pett, J. Chem. Soc. Dal-
ton Trans. (1994) 3311.
[26] J.D. Scott, R.J. Puddephatt, Organometallics 2 (1983) 1643.
[27] J.L. Spencer, Inorg. Synth. XIX (1979) 213.
.
.