Synthesis and reactivity of group 6 and 10 complexes of the bis(dialkylaminophosphanyl)imine iPrN = C[CH2P(NiPr2)2]2

Article abstract of DOI:10.1002/1099-0682(200203)2002:3<732::AID-EJIC732>3.0.CO;2-2

The coordination behaviour of the readily prepared, potentially ambidentate, bis(α,α′-phosphanyl)imine (iPr₂N)₂-PCH₂C (=NiPr)CH₂P(NiPr₂)₂ (1, PNP) has been investigated, Treatment of pallad

Full text of DOI:10.1002/1099-0682(200203)2002:3<732::AID-EJIC732>3.0.CO;2-2

FULL PAPER
Synthesis and Reactivity of Group 6 and 10 Complexes of the
Bis(dialkylaminophosphanyl)imine iPrN؍C[CH2P(NiPr2)2]2
Francoise Dahan,[a] Philip W. Dyer,*[b] Martin J. Hanton,[b] Matthew Jones,[b]
¸
D. Michael P. Mingos,[c,d] Andrew J. P. White,[c] David J. Williams,[c] and
Anna-Maria Williamson[c]
Keywords: P,N ligands / Chelates / Diaminophosphanes / Imines / Palladium
The coordination behaviour of the readily prepared, poten- fashion with a non-coordinating bis(diisopropylamino)phos-
tially ambidentate, bis(α,αЈ-phosphanyl)imine (iPr2N)2-
PCH2C(=NiPr)CH2P(NiPr2)2 (1, PNP) has been investigated.
Treatment of palladium(II), platinum(II), chromium(0), and
phanyl-substituted pendant arm. Ligand 1 and complexes
[PdCl2(PNP-κ2P,N)] (2) and [Mo(CO)4(PNP-κ2P,N)] (10) were
characterised in the solid state by X-ray crystallography. The
molybdenum(0) sources with ligand 1 afforded complexes in preparation of cationic PdII derivatives of PNP is discussed.
which 1 was coordinated solely in a bidentate P,N-chelating
Introduction
in part, to the ease with which phosphorusϪheteroatom
bonds can be formed, as exemplified by PϪO and PϪN
moieties. Diaminophosphanes have been targeted for study
as they exhibit enhanced σ-donor strength (basicity) when
compared with arylphosphanes and even triaminophos-
phanes, yet are often more easily prepared than strongly
basic alkylphosphanes.[2h]
As the number of stoichiometric and catalytic applica-
tions involving hetero-bifunctional ligands increases,[3,4]
simple, high-yielding syntheses of such species are of par-
ticular interest. Recently, we have reported the simple, ‘‘one-
pot’’ synthesis of the bis(α,αЈ-phosphanyl)-substituted im-
ines, e.g. PNP (1; Figure 1).[5] These compounds are rare
examples of a potentially chelating diaminophosphane-con-
taining ‘‘hybrid’’ ligand. However, the presence of one im-
ino- and two phosphanyl-donor sites permits 1 to poten-
tially adopt a number of different coordination modes, ex-
amples of which are outlined in Figure 1. Here we report
preliminary studies of the coordination chemistry of this
ligand, with particular emphasis placed on investigating its
mode of binding.
There is continued interest in hetero-bifunctional ‘‘hy-
brid’’ ligands, which possess two chemically distinct donor
sites that are each able to interact to a different extent with
a chelated metal centre (e.g. one soft and one hard
donor).[1] The asymmetry present in systems of this type
offers a degree of selectivity in reactions occurring at the
metal centre, due to the electronic and steric disparity be-
tween the two different donor groups. In addition, it has
been suggested that ligands of this type confer a ‘‘flexible’’
coordination environment at the metal centre, such that a
vacant coordination site can be generated reversibly, with-
out complete dissociation of the ligand (so-called ‘‘hemil-
ability’’). This feature is of considerable importance in cata-
lysis and, since phosphanes are essential components in nu-
merous industrially relevant catalytic processes, it is perhaps
not surprising that many of the best-studied ‘‘hybrid’’ sys-
tems contain a P-donor constituent.
Currently there is a considerable resurgence in the use of
heteroatom substituents at phosphorus to ‘‘tune’’ the steric
demands and basicity of phosphane ligands.[2] This is due,
Results and Discussion
[a]
Laboratoire de Chimie de Coordination,
205 route de Narbonne, 31077 Toulouse, Cedex 4, France
[b]
Department of Chemistry, University of Leicester,
Neutral Palladium(II) Derivatives
University Road, Leicester, LE1 7RH, UK
Fax: (internat.) ϩ 44-116/252-3789
E-mail: p.dyer@le.ac.uk
The dichloro complex [PdCl2(PNP-κ2P,N)] (2) is readily
prepared through addition of PNP (1), prepared as re-
ported previously,[5] to a dichloromethane solution of
[PdCl2(NCPh)2] at ambient temperature, the reaction reach-
ing completion within 1 h according to 31P{1H} NMR
spectroscopy (Scheme 1). Removal of volatile components
[c]
Department of Chemistry, Imperial College,
Exhibition Road, South Kensington, London, SW7 2AY, UK
[d]
Current address: St. Edmund Hall, University of Oxford,
Queens Lane, Oxford OX1 4AR, UK
Supporting information for this article is available on the
WWW under http://www.eurjic.com or from the author.
732
WILEY-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002 1434Ϫ1948/02/0303Ϫ0732 $ 17.50ϩ.50/0 Eur. J. Inorg. Chem. 2002, 732Ϫ742

Group 6 and 10 Complexes of iPrNϭC[CH2P(NiPr2)2]2
FULL PAPER
the free and bound phosphane components of 2 over the
temperature regime Ϫ80 to ϩ40 °C. The 1H NMR spectro-
scopic data for the PNP moiety are little changed following
its coordination to the palladium centre with the two
methylene resonances being obtained at δ ϭ 2.94 (s) and
2
δ ϭ 3.61 (d, JPH ϭ 11.6, endocyclic CH2), although the
latter clearly exhibits a coupling to the phosphorus atom;
1
both CH2 groups appear as singlets in the H NMR spec-
trum of 1.[5] Similarly, 13C NMR spectroscopy clearly dis-
tinguishes the two different CH2 environments: δ ϭ 54.4
1
3
1
(dd, JPC ϭ 35.6, JPC ϭ 10.8 Hz) and 38.5 (dd, JPC
ϭ
3
20.6, JPC ϭ 9.8 Hz). The former has been assigned to the
endocyclic methylene group based on its coordination
chemical shift change (∆δ ഠ 10 ppm). As expected, the im-
ine carbon atom appears as a doublet of doublets at δ ϭ
Figure 1. Ligand 1 and its potential binding modes
in vacuo, followed by washing with dry hexane affords 2 as
a yellow, air-stable, analytically pure powder in 90% yield,
176.6 (2JPC ϭ 16.5, 8.3 Hz), exhibiting a downfield shift
which exhibits
a
fragment ion at m/z
ϭ
702
2
compared with uncoordinated 1 [δ ϭ 166.0 (dd, JPC
ϭ
{[PdCl(PNP)]ϩ} by mass spectrometry.
15.0, 9.5 Hz)].
Table 1. 31P NMR spectroscopic data for PNP (1) and its com-
plexes
Compound
Solvent
CDCl3
31P{1H}
4
1
ϩ53.1 (d, JPP ϭ 14.5 Hz),
ϩ46.2 (d, JPP ϭ 14.5 Hz)[a]
4
2
3
4
5
6
CDCl3
CDCl3
CDCl3
CDCl3
CDCl3
ϩ100.9 (s), ϩ51.9 (s)[b]
ϩ112.6 (s), ϩ49.3 (s)[c]
ϩ114.5 (s), ϩ49.8 (s)[c]
ϩ113. 2 (s), ϩ48.9 (s)[b]
ϩ82.1 (1JPPt ϭ 6007.0), ϩ49.0 (s)
ϩ70.2 (1JPPt ϭ 4565.0), ϩ51.3 (s)
ϩ108.4 (s), ϩ52.8 (s),
7
CDCl3
1
Ϫ [c]
Ϫ143.4 (sept, JPF ϭ 706.5, PF6
)
8
9
10
11
CDCl3
CDCl3
C6D6
ϩ108.4 (s), ϩ52.8 (s)[c]
ϩ108.4 (s), ϩ52.9 (s)[c]
ϩ132.1 (s), ϩ51.4 (s)[d]
ϩ158.3 (s), ϩ50.3 (s)[d]
CDCl3
[a]
[b]
[c]
[d]
81.0 MHz. 122.0 MHz. 101.3 MHz. 109.4 MHz.
Preparation of 2 through reaction of 1 with [PdCl2(cod)]
(cod ϭ 1,5-cyclooctadiene) was considerably slower (ca. 2
d) than with [PdCl2(NCPh)2]. This observation is presumed
to reflect the higher barrier to dissociation of the chelating
cod ligand, compared with that for benzonitrile, and is con-
sistent with the observation that [PdCl2(tmeda)] does not
react with PNP.
Scheme 1. Reagents and conditions: i: trans-[PdCl2(NCPh)2],
CH2Cl2, room temp., 2 h; ii: [PdX(Me)(cod)] (X ϭ Cl, Br), CH2Cl2,
room temp., 1 h; iii: NaY {Y ϭ PF6, [B{3,5-(CF3)2C6H3}4]},
CH3CN, room temp., 3 d; iv: [PdMe2(tmeda)], CH2Cl2, room
temp., 2 d; v: [PtCl(Me)(cod)], CDCl3, room temp., 3 d; vi: cis-
[Mo(CO)4(pip)2], CH2Cl2, room temp., 18 h; vii: fac-
[Cr(CO)3(NCMe)3], toluene, room temp., 2 d
In contrast, 1 reacted rapidly at room temperature with
The 31P{1H} NMR spectrum of complex 2 exhibits two dichloromethane solutions of [PdX(Me)(cod)] to afford
sharp resonances at δ ϭ ϩ100.9 (s) and ϩ51.9 (s). The con- [PdX(Me)(PNP-κ2P, N )] [X ϭ Cl (3), Br (4)] quantitatively
siderable downfield shift of only one of the two resonances within 1 h, according to 31P NMR spectroscopy
associated with 1 (Table 1) upon coordination (∆δ ഠ (Scheme 1). Complexes 3 and 4 could be isolated as air-
50 ppm) suggests that in 2 the PNP ligand (1) is coordin- stable, cream solids in 85 and 72% yields, respectively. The
ated in a bidentate P,N-chelating bonding mode (I; Fig- 31P{1H} NMR spectra suggest that ligand 1 again adopts a
ure 1), with a pendant bis(diisopropylamino)phosphane P,N-chelating bonding mode (I; Figure 1), with the forma-
4
arm.[6] The lack of any detectable JPP coupling constant tion of a single isomer in each case [e.g. 3: δ: ϩ112.6 (s),
for 2 could result either from an alteration in the angle be- ϩ49.3 (s)] (Table 1). In contrast with 2, the endocyclic CH2
2
4
tween the two phosphorus centres or from the change in resonance from 3 now displays both JPH and JPH coup-
hybridization of the phosphorus atom upon coordination.[7] lings (overlapping resonances obscure the signal for 4). The
There is no evidence by NMR of any exchange between presence of one methyl ligand environment was confirmed
Eur. J. Inorg. Chem. 2002, 732Ϫ742
733

P. W. Dyer et al.
FULL PAPER
by both 1H [e.g. 3: δ ϭ 0.71 (s)] and 13C [e.g. 3: δ ϭ 0.8 (d)] ϩ55.7) with concomitant liberation of ligand 1, according
1
NMR spectroscopy. The H NMR chemical shifts associ- to 31P{1H} NMR spectroscopy.[12]
ated with the methyl ligand are comparable to those ob-
served for related [PdCl(Me)(PЈ,NЈ)] complexes (ca. 0.7
ppm).[8,9] Resonances corresponding to the exo- and endo-
cyclic CH2 groups are readily detected by 13C NMR spec-
troscopy for 3 and 4. Again, neither 3 nor 4 showed any
evidence for exchange of the free and bound phosphane
moieties.
Neutral Platinum(II) Derivatives
Attempts were made to prepare the analogous plat-
inum(II) complexes of PNP. Somewhat surprisingly, no re-
action was observed between either [PtCl2(cod)] or
[PtCl2(NCR)2] (R ϭ Me, Ph) and ligand 1 in chlorinated
solvents even at elevated temperatures (under rigorously dry
and anaerobic conditions). In each case, 1 could be reco-
vered unchanged. However, displacement of cod from un-
symmetrical [PtCl(Me)(cod)] by 1 proved more facile (vide
supra). After 3 d at room temp., [PtCl(Me)(PNP-κ2P,N)]
(6a,b) was obtained as a mixture of trans and cis isomers
according to 31P NMR spectroscopy (20:1) in CDCl3, the
product in which the phosphorus atom lies trans to the
2
The small magnitudes of the JPϪPdϪC coupling con-
stants associated with the methyl ligands (3: 7.3 Hz; 4:
9.0 Hz) suggest that both complexes 3 and 4 adopt a struc-
ture in which the strongly trans-influencing methyl group
lies trans to the weakly trans-influencing imine N-atom, i.e.
the thermodynamically favoured form.[10] This is consistent
with data from other palladium complexes possessing a
P,N-ligand.[11] However, Boersma has indicated that cau-
tion must be used when spectroscopic methods are em-
ployed to assign cis/trans configurations about Pd for these
types of complex.[8] The geometric assignment for complex
3 is strongly supported by a combination of COSY and
NOE NMR experiments.
chloride ion (6a) being the major species (1JPtP
6007.0 Hz). No interconversion of isomers was observed on
prolonged heating.
ϭ
Cationic Palladium(II) Derivatives
Attempts were made to prepare the corresponding di-
Part of our interest in group 10 complexes of the
methyl complex, [PdMe2(PNP-κ2P,N)], by methylation of sterically demanding ligand PNP, arises from their potential
complexes 2, 3, and 4 with Me2LiCu, MeLi, or MeMgBr to serve as precursors to the corresponding cationic PdII
at low temperatures by analogy with previous work.[12] In salts for application in olefin oligomerisation and poly-
each case, an inseparable mixture of products, including merisation.[14,15] Initial, unsuccessful attempts to prepare
some resulting from deprotonation of the coordinated PNP the desired alkyl cations focussed on halide abstraction
ligand methylene backbone, was obtained on warming to from acetonitrile solutions of the dichloro and chloro(me-
room temperature. There was no evidence for the genera- thyl) complexes 2 and 3, respectively, using a variety of sil-
tion of any PdϪMe species.
ver salts. In each case, oxidation and subsequent decom-
In contrast, treating a dichloromethane solution of the position of the P,N-ligand accompanied by precipitation of
known [PdMe2(tmeda)] complex with 1 equiv. of ligand 1 colloidal palladium was observed.
cleanly afforded a single new product, which has tentatively
In contrast, halide abstraction from 3 using 1 equiv. of
been assigned as [PdMe2(PNP-κ2P,N)] (5), according to NaY (Y ϭ PF6, [B{3,5-(CF3)2C6H3}4]) proceeded cleanly in
31P{1H} NMR spectroscopy [δ ϭ ϩ113.2 (s), ϩ48.9 (s)] in acetonitrile at room temperature to afford the monocationic
77% yield (Scheme 1).[9] Complete displacement of tmeda acetonitrile adducts [PdMe(NCCH3)(PNP-κ2P, N )]Y {Y ϭ
by PNP occurred within 2 d at room temperature. The ex- PF6 (7);
Y
ϭ
[B{3,5-(CF3)2C6H3}4] (8)} (Table 1,
change is presumably aided by the strong trans influence of Scheme 1), which could be isolated as moisture-sensitive,
the two methyl groups that facilitate dissociation of the di- yellow/brown solids. Elemental analyses and variable-tem-
1
amine.
perature H NMR spectroscopy confirmed the presence of
1
Problems were encountered, however, with the H and acetonitrile in both complexes. At 300 K complex 7 presents
13C NMR spectra associated with 5. In both cases, only a a broadened resonance at δ ϭ 2.33 (ν1/2 ϭ 11 Hz), which is
single resonance attributable to a palladium-bound methyl replaced by two singlets (δ ϭ 2.45 and 2.04) in a 50:1 ratio
ligand could be detected [1H: δ ϭ 0.73 (d, JPH 0.9 Hz); at 243 K, corresponding to bound and a trace of residual
3
13C: δ ϭ Ϫ0.6 (d, JPC 7.8 Hz)]. Variable-temperature, T1, free CH3CN, respectively. [Pure acetonitrile displays a single
2
and correlated H/13C NMR spectra were obtained but did resonance at
δ ϭ
2.04 by 1H NMR spectroscopy
1
not aid identification.
(400.1 MHz, CDCl3) at 243 K.] This behaviour has been
The correct formulation of 5 as [PdMe2(PNP-κ2P,N)] attributed to the CH3CN ligand of 7 undergoing slow ex-
was suggested by mass spectrometry, which exhibited ions change with any residual CH3CN at 300 K, a process that
at m/z ϭ 681 and 695 corresponding to the species no longer occurs at lower temperatures. Similarly, complex
[PdH(Me)(PNP)]ϩ and [PdMe2(PNP)]ϩ, respectively. Ele- 8 exhibits a single resonance at δ ϭ 2.23 (300 K), which
mental analyses were irreproducible and inconclusive, pos- is resolved into two signals at 243 K (δ ϭ 2.30 and 2.04)
sibly as a result of the lack of long-term thermal stability corresponding to bound and free CH3CN, respectively.
of the dimethyl complex. However, further support for the
Surprisingly, treatment of 3 with NaBPh4 under identical
formation of the desired species was obtained by treating a reaction conditions resulted in the formation of the aceton-
sample of 5 with 1 equiv. of dppe in dichloromethane. This itrile-free salt [PdMe(NCCH3)(PNP-κ2P,N)][BPh4] (9), as
cleanly afforded the known [PdMe2(dppe)] complex (δ ϭ confirmed by both elemental analyses and variable-temper-
734
Eur. J. Inorg. Chem. 2002, 732Ϫ742

Group 6 and 10 Complexes of iPrNϭC[CH2P(NiPr2)2]2
FULL PAPER
ature 1H NMR spectroscopy. Indeed, the room-temperature city of the chelating ligand 1, although some caution must
1H NMR spectrum of a freshly prepared CDCl3 solution be observed when comparing carbonyl stretching frequen-
of 9 shows no evidence of free or bound acetonitrile. On cies of unsymmetrical chelate complexes.[2c,2h]
lowering the temperature to 243 K, a small resonance cor-
Treating a dichloromethane solution of [Mo(CO)4(pip)2]
responding to a trace of residual unbound CH3CN was de- (pip ϭ piperidine) with an equimolar amount of chelate
tected (δ ϭ 2.04), despite extended drying of the solid 1 cleanly afforded the six-coordinate carbonylmolybdenum
sample of 9 under high vacuum. There was no indication complex [cis-Mo(CO)4(PNP-κ2P,N)] (10) in 64% yield after
of bound acetonitrile. Addition of 1.1 equiv. of CH3CN to 18 h at room temperature. The complex was isolated, after
this sample, followed by cooling to 243 K, merely increased workup, as an air-stable crystalline solid. Data from both
the intensity of the signal corresponding to unbound 31P{1H} NMR and infrared spectroscopy are consistent
CH3CN.
with ligand 1 being coordinated in a bidentate, P,N fashion
The coordination of the tetraphenylborate anion to elec- [δ ϭ ϩ132.1 (s), ϩ51.4 (s)] (mode I; Figure 1). A compound
tron-deficient metal centres is now well documented.[16] which possesses identical spectroscopic data to those ob-
Thus, it seems reasonable to suggest that the formation of tained for 10 was isolated in low yield (28%) from the reac-
complex 9 as a base-free species has to be attributed to the tion of 1 with [Mo(CO)3(cht)] (cht ϭ η6-cycloheptatriene).
presence of the [BPh4]Ϫ anion presumably as a result of ion In the latter case, the formation of 10 is believed to result
1
pairing. However, variable-temperature H NMR spectro- from carbon monoxide scrambling.
scopy, over the temperature regime 243Ϫ300 K, could not
As was observed for the palladiumϪPNP derivatives,
establish the nature of the cationϪanion interaction for 9. complex 10 is rigid on the NMR timescale, with no in-
The possibility of intermolecular coordination of the pen- terconversion of the free and bound phosphane compon-
dant diaminophosphane arm or a monomer/dimer equilib- ents being detectable. The infrared spectroscopic data from
rium was, however, clearly ruled out by 31P NMR spectro- complex 10 reveal that the presence of the diisopropylam-
scopy (243Ϫ300 K).
ino substituents on the phosphane component does render
Salts 7 and 8 are stable in acetonitrile solution and in the ligand 1 slightly more basic when compared with the values
solid state under nitrogen (months). Complex 8 is also of the range of carbonyl stretching frequencies observed for
stable in CDCl3 solution, but both 7 and 9 decompose similar P,N-ligands bearing a diphenylphosphane moiety
slowly in dry chlorinated solvents (24 h at room temp.). bound to the Mo(CO)4 fragment (Table 2). However, ligand
Despite the differences in structure, complexes 7؊9 exhibit 1 remains considerably less basic than the strongly σ-donat-
virtually identical 31P NMR spectra, in both CD3CN and ing
bis(pyrrolyl)-substituted
diphosphane,
(pyrro-
CDCl3. As for the neutral PdII derivatives, 13C NMR spec- lyl)2P(CH2)2P(pyrrolyl)2 [νCO ϭ 2044, 1970, 1916 cmϪ1],
troscopy readily distinguishes two CH2 environments for which possesses related diaminophosphane components, as
the cationic derivatives 7؊9. Just as was observed for 3 the a result of aromatic delocalisation of the nitrogen lone pair
1H NMR spectra of these complexes display both 2JPH and in the latter.[2b]
˜
4JPH couplings to the endocyclic CH2 resonance.
In the olefin polymerisation arena, high catalytic activit-
ies have been achieved by combining sterically encumbered
metal alkyl cations with a noncoordinating anion such as
the perfluorinated analogue of BPh4, [B(C6F5)4]Ϫ.[17]
Hence, a number of attempts were made to prepare the pal-
ladium PNP salts of this anion. Both halide elimination
from 3, using Li[B(C6F5)4], and alkyl abstraction from the
proposed dimethyl complex 5 by [Ph3C][B(C6F5)4], led to
intractable mixtures of largely unidentifiable but similar
products according to NMR spectroscopy, when performed
under rigorously dry and anaerobic conditions. However,
for the latter reaction, the formation of Ph3CH was evident
presumably as a result of hydride abstraction by the trityl
cation. There was no evidence of C6F5-group transfer to the
metal centre.
Table 2. Representative metalϪcarbonyl stretching frequencies ob-
served for [Mo(CO)4(κ2P,N)] complexes
Carbonylmetal Coordination Chemistry
The potential for ligand 1 to adopt a number of different
coordination modes is readily apparent (Figure 1). Thus, in
order to probe the coordination behaviour of PNP (1), sub-
Treatment
of
a
toluene
solution
of
fac-
stitution reactions between 1 and a number of group 6 car- [Cr(CO)3(NCCH3)3] with 1 mol-equiv. of 1 afforded a single
bonyl complexes were undertaken. Subsequently, examina- phosphorus-containing product according to 31P{1H}
tion of the metalϪcarbonyl stretching frequencies from the NMR spectroscopy [δ ϭ ϩ158.3 (s) and ϩ50.3 (s)] after 2
resulting complexes can be used to assess the relative basi- d at room temp. Cooling (Ϫ30 °C, 12 h) of a concentrated
Eur. J. Inorg. Chem. 2002, 732Ϫ742
735

P. W. Dyer et al.
FULL PAPER
toluene/pentane solution of the crude mixture produced were observed by 31P{1H} NMR spectroscopy. Similar re-
yellow/orange microcrystals in a low yield (23%).
activity is observed when the oxidative addition of alkyl
1
The 31P, H, and 13C NMR spectroscopic data are con- halides is attempted with 1.
sistent with the formulation of this product as the
Molecular Structure Determinations
mono(acetonitrile) adduct, fac-[Cr(CO)3(NCCH3)(PNP-
κ2P,N)] (11), with 1 again adopting a mode I coordination
(Figure 1).
Surprisingly few metal complexes of chelating ligands
bearing a diaminophosphane unit rather than a dialkyl- or
diarylphosphane
have
been
structurally
charac-
In the IR spectrum of 11, recorded under rigorously dry,
anaerobic conditions (KBr, Nujol), no CϪN absorption
corresponding to bound CH3CN could be detected. For
comparison, an IR spectrum of an authentic sample of fac-
[Cr(CO)3(NCMe)3] [C9H9N3O3Cr (259.18): calcd. C 41.71,
H 3.50, N 16.21; found C 41.79, H 3.39, N 16.09] was re-
corded under identical conditions. In contrast to the ori-
ginal work,[40] no CN absorption was detectable at 2280
cmϪ1, despite the carbonyl regions being identical [experi-
mentally observed IR (Nujol): ν˜ ϭ 1915, 1782 cmϪ1]. Nei-
ther decomposition nor the appearance of free CH3CN was
observed over a period of approximately 30 min.
terised.[2c,26,27] This prompted an investigation of the mo-
lecular structures of ligand 1 and complexes 2 and 10 in the
solid state.
The crystal structure of 1 revealed that the geometric
parameters associated with the imine moiety [CϭN 1.268(4)
˚
A, C(3)ϪN(1)ϪC(4) 122.8(2)°, sum of angles about C(3) ϭ
360.0°] are typical of this functionality (Figure 2,
Table 3).[2c] A staggered conformation is adopted such that
the lone pair of phosphorus atom P(1) is directed away from
those on both the imine nitrogen N(1) and the second phos-
phorus atom P(2). As is observed for many aminophos-
phanes, the four PϪN bond lengths are significantly shorter
than that associated with a true PϪN single bond, the sums
of angles about nitrogen atoms N(2) to N(5) [358.4, 359.9,
360.0, 360.0°, respectively] indicating significant sp2 charac-
ter;[28] together this suggests there is a degree of lone pair
donation from the nitrogen atom to the phosphorus atoms.
The isolation of an octahedral group 6, tricarbonyl/
mono(acetonitrile) complex bearing a bidentate ligand is
not without precedent.[23] The formation of a bridged spe-
cies of the type [{Cr(CO)5}2(PNP-κ2P, P )], resulting from
CO scrambling, is clearly ruled out by 31P NMR spectro-
1
scopy.[24] Both the H and 13C NMR spectra show some
line broadening, which appears temperature-independent
(Ϫ45 to ϩ40 °C). This suggests the presence of traces of a
paramagnetic chromium species rather than any flux-
ionality associated with 11. Such an explanation is rein-
forced by the broadened signals observed for the residual
protio impurities of the deuterated NMR solvents. All at-
tempts to further purify 11 were unsuccessful and resulted
in decomposition. Prolonged cooling of the reaction mix-
ture containing 11 eventually yielded inseparable mixtures
of Cr(CO)6 and 11. Simply heating a toluene solution con-
taining equimolar amounts of 1 and hexacarbonylchrom-
ium resulted in the formation of an intractable mixture of
unidentified products with no evidence consistent with the
formation of 11.
Investigation of the Reactivity of the Pendant
Diaminophosphane Arm
Since complexes 2؊11 all possess a pendant, non-coordi-
nating diaminophosphane moiety, it was of interest to in-
vestigate the reactivity of this group. Preliminary studies
employing [PdCl2(PNP-κ2P, N )] (2) are somewhat surpris-
ing. In dry dichloromethane solution, no reaction was ob-
served at either of the two phosphorus centres with molecu-
lar oxygen, sulfur, BH3(THF), Me3SiN3, or [Mo(C-
O)5(THF)]. In contrast, 1 reacted rapidly with elemental
sulfur.[5] A similar lack of reactivity towards boranes or
chalcogens was noted for the free phosphane arm of 10.
Figure 2. Molecular structure of PNP (1)
˚
Table 3. Selected bond lengths [A] and angles [°] for ligand PNP (1)
P(1)ϪN(3)
P(1)ϪC(1)
P(2)ϪN(4)
N(1)ϪC(3)
C(2)ϪC(3)
1.691(2)
1.870(3)
1.687(2)
1.268(4)
1.509(4)
P(1)ϪN(2)
P(2)ϪN(5)
P(2)ϪC(2)
C(1)ϪC(3)
1.698(2)
1.703(2)
1.857(3)
1.502(4)
It is noteworthy that despite the well-documented reactiv- N(3)ϪP(1)ϪN(2)
110.0(1)
99.5(1)
100.7(1)
122.8(2)
117.1(2)
117.0(2)
N(3)ϪP(1)ϪC(1)
N(5)ϪP(2)ϪN(4)
N(4)ϪP(2)ϪC(2)
C(3)ϪC(1)ϪP(1)
N(1)ϪC(3)ϪC(2)
C(2)ϪC(3)ϪC(1)
102.6(1)
109.7(1)
102.3(1)
114.8(2)
126.9(2)
116.1(2)
N(2)ϪP(1)ϪC(1)
ity of PϪN bonds towards protic reagents, complexes 2, 3,
N(5)ϪP(2)ϪC(2)
and 4 were found stable to alcoholysis, even in neat anhyd-
C(3)ϪN(1)ϪC(4)
rous methanol.[25] However, when solutions of complex 2
C(3)ϪC(2)ϪP(2)
were treated with 1 equiv. of either methyl iodide or benzyl
N(1)ϪC(3)ϪC(1)
bromide (CH2Cl2, Ϫ30 °C), many unidentifiable products
736
Eur. J. Inorg. Chem. 2002, 732Ϫ742

Group 6 and 10 Complexes of iPrNϭC[CH2P(NiPr2)2]2
FULL PAPER
The molecular structure determination of complex 2 bond lengths PdϪCl(1) and PdϪCl(2) of 2.412(2) and
˚
(Figure 3, Table 4) revealed a near square-planar geometry, 2.306(3) A, respectively, reflects the larger trans influence of
the palladium centre and its four coordinated atoms being phosphorus compared to nitrogen.[30]
˚
co-planar to within 0.049 A, with a cis-PdCl2 arrangement.
Following its complexation to the PdCl2 fragment, ligand
No inter- or intramolecular interaction of the pendant pho- 1 adopts a folded envelope conformation with C(3) and
˚
sphane P(2) was observed, the closest intermolecular con- C(1) lying 0.37 and 0.88 A, respectively, ‘‘above’’ the coor-
˚
tact being 4.93 A to Cl(2). The P(1)ϪPd and N(1)ϪPd dination plane a geometry that results from the presence of
˚
bond lengths of 2.197(2) and 2.112(7) A, respectively, and the planar CϭN moiety. There is little perturbation of the
the P(1)ϪPdϪN(1) angle of 81.7(2)° are entirely consistent metrical parameters for the imine fragment [C(3)ϪN(1)
with those reported for similar PdII complexes.[11,29] The 1.293(11) A, C(3)ϪN(1)ϪC(4) 119.2(7)°, sums of angles at
˚
non-equivalence observed for the two palladiumϪchlorine C(3) and N(1) 360.0 and 359.9°, respectively]. Similarly, the
geometry around each of the four amino nitrogen atoms
N(2) to N(5) remains essentially planar (sum of angles
359.4, 359.9, 359.5, and 359.3°, respectively). The PϪN
bond lengths in the non-coordinated aminophosphane moi-
˚
ety [P(2)ϪN(4) 1.697(8); P(2)ϪN(5) 1.690(8) A] are both
marginally longer than their counterparts [P(1)ϪN(2)
˚
1.669(6), P(1)ϪN(3) 1.647(7) A] in the metal-bound com-
ponent. As in the free ligand 1, these distances are signific-
antly shorter than the values quoted for a PϪN single
bond,[28] but are in line with those of other structurally
characterised coordinated aminophosphanes.[2c,26,27,31]
For comparison, the crystal structure of 10 was also de-
termined and is presented in Figure 4 with selected bond
lengths and angles given in Table 5. The comparatively
small PϪN ‘‘bite angle’’ [P(1)ϪMoϪN(1) 75.96(9)°] of li-
gand 1 results in a distorted octahedral geometry about the
˚
molybdenum centre. The metal atom lies only 0.011 A from
the equatorial plane formed by atoms P(1), N(1), and the
two carbonyl ligands C(31) and C(32), which are coplanar
˚
to within 0.042 A. The contracted geometry at the molyb-
denum centre caused by the small bite angle of the chelating
ligand is compensated in the equatorial plane by an increase
in both the adjacent angles P(1)ϪMoϪC(32) and
Figure 3. Molecular structure of [PdCl2(PNP-κ2P,N)] (2)
N(1)ϪMoϪC(31) to 95.8(2) and 100.4(2)°, respectively. The
two pseudo-axial carbonyl ligands bend slightly away from
the chelating ligand [C(33)ϪMoϪC(34) 171.8(2)°]. As was
observed for the palladium complex 2, the PϪN-metallacy-
cle adopts a folded envelope conformation with C(3) and
C(1) lying 0.25 and 0.77 A, respectively, ‘‘above’’ the coor-
˚
Table 4. Selected bond lengths [A] and angles [°] for complex 2
˚
dination plane. Again the metric parameters of the imine
fragment [N(1)ϪC(3) of 1.287(5) A, C(3)ϪN(1)ϪC(4)
PdϪN(1)
2.112(7)
2.306(3)
1.647(7)
1.838(8)
1.697(8)
1.293(11)
1.504(12)
PdϪP(1)
2.197(2)
2.412(2)
1.669(6)
1.690(8)
1.880(8)
1.518(10)
˚
PdϪCl(2)
P(1)ϪN(3)
P(1)ϪC(1)
P(2)ϪN(4)
N(1)ϪC(3)
C(2)ϪC(3)
PdϪCl(1)
P(1)ϪN(2)
P(2)ϪN(5)
P(2)ϪC(2)
C(1)ϪC(3)
117.9(4)°] differ little from those for the free ligand 1, with
both N(1) and C(3) remaining essentially planar (sums of
angles around both atoms 360°). Similarly, the P(1)ϪN
bond lengths, and the geometries about N(2) and N(3),
show little alteration from those of the free ligand. The
˚
MoϪN(1) bond length [2.356(4) A] is comparable with
N(1)ϪPdϪP(1)
P(1)ϪPdϪCl(2)
P(1)ϪPdϪCl(1)
N(3)ϪP(1)ϪN(2)
N(2)ϪP(1)ϪC(1)
N(2)ϪP(1)ϪPd
N(5)ϪP(2)ϪN(4)
N(4)ϪP(2)ϪC(2)
C(3)ϪN(1)ϪPd
C(3)ϪC(1)ϪP(1)
N(1)ϪC(3)ϪC(2)
C(2)ϪC(3)ϪC(1)
81.7(2)
N(1)ϪPdϪCl(2)
N(1)ϪPdϪCl(1)
Cl(2)ϪPdϪCl(1)
N(3)ϪP(1)ϪC(1)
N(3)ϪP(1)ϪPd
C(1)ϪP(1)ϪPd
N(5)ϪP(2)ϪC(2)
C(3)ϪN(1)ϪC(4)
C(4)ϪN(1)ϪPd
C(3)ϪC(2)ϪP(2)
N(1)ϪC(3)ϪC(1)
171.4(2)
100.8(2)
87.51(9)
109.0(4)
111.7(3)
99.4(3)
102.8(4)
119.2(7)
121.1(5)
113.1(6)
117.9(7)
other MoϪN σ-donor bonds.[29,31] The greater trans influ-
ence of phosphorus over nitrogen is reflected in the
molybdenumϪcarbonyl bond lengths of the equatorial car-
bonyl ligands with that to C(31) being significantly longer
90.12(9)
176.86(8)
109.5(4)
104.1(4)
121.7(3)
111.3(4)
98.2(4)
119.6(5)
107.5(6)
127.0(7)
115.1(7)
˚
than that to C(32) [MoϪC(31) 1.987(6) A, MoϪC(32)
˚
1.940(6) A]. The molybdenumϪphosphorus bond length of
[22,29,33]
˚
2.5367(11) A [P(1)ϪMo] is unremarkable.
There are
no short inter- or intramolecular interactions involving the
pendant phosphane P(2), the closest intermolecular contact
˚
being 5.46 A to O(32).
Eur. J. Inorg. Chem. 2002, 732Ϫ742
737

P. W. Dyer et al.
FULL PAPER
chemistry of PNP-containing complexes. The incorporation
of amino rather than alkyl or aryl groups at the phosphorus
atoms considerably facilitates greater variation of the steric
and electronic properties of the ligand. X-ray crystallo-
graphy clearly demonstrates the considerable steric de-
mands of ligand 1, the isopropyl substituents dominating
the molecular structures of complexes 2 and 10. Further-
more, the amino substituents at the phosphorus atoms that
are simultaneously σ-electron-withdrawing but π-electron-
donating, render the phosphane comparatively electron-
rich. This is something that is likely to have a profound
effect on the nature of the metalϪphosphorus interaction
and hence on the chemistry of the metal complexes.[2c][2h]
The apparent lack of reactivity of the pendant, non-co-
ordinated, diaminophosphane unit warrants additional
study. If the reactions at this site can be controlled, then
this ‘‘arm’’ could be exploited as a means of ‘‘immobilis-
ing’’ these complexes on insoluble support materials such
as silica or cross-linked polystyrenes. Further coordination
chemistry and catalysis studies are on-going.
Figure 4. Molecular structure of [Mo(CO)4(PNP-κ2P,N)] (10)
Experimental Section
˚
Table 5. Selected bond lengths [A] and angles [°] for complex 10
All manipulations were performed under nitrogen using standard
Schlenk and cannula techniques or in a conventional nitrogen-filled
glove box. Solvents were freshly distilled under nitrogen from so-
dium/benzophenone (tetrahydrofuran, diethyl ether, toluene), from
calcium hydride (dichloromethane, acetonitrile), from sodium (hex-
ane, pentane), or from P2O5 (C6D6, CD3CN, and CDCl3) and de-
gassed prior to use. Elemental analyses were performed by the mic-
roanalytical services of Imperial College or by S. Boyer at the Uni-
versity of North London. NMR spectra were recorded with a
Bruker AC200, AM 250, AMX 300, AMX 400, or JEOL 270;
chemical shifts were referenced to residual protio impurities in the
deuterated solvent (1H), to the deuterated solvent (13C), external
CFCl3 (19F), or to external aqueous 85% H3PO4 (31P). All spectra
were obtained at ambient probe temperatures unless stated other-
wise. Infrared spectra were recorded [Nujol mulls (KBr windows),
KBr discs, or in solution (KBr windows)] with either
PerkinϪElmer 1600 or Mattson Research Series 1 spectrophoto-
meters; Nujol was dried over sodium wire. Mass spectra were re-
corded with either Kratos Concept 1H or AutospecQ instruments
and are reported in (m/z). PNP (1),[5] cis-[Mo(CO)4(pip)2],[34] fac-
[Cr(CO)3(NCCH3)3],[35] trans-[PdCl2(NCPh)2],[36] [PdCl2(cod)],[37]
[PdCl2(tmeda)], [PdMe2(tmeda)],[9] [PdCl(Me)(cod)],[38] [PtCl(Me)-
(cod)],[11b] and Na[B{3,5-(CF3)2C6H3}4][39] were prepared accord-
ing to literature procedures. [PdBr(Me)(cod)] was prepared using a
procedure based on that used for the preparation of [PdCl(Me)-
(cod)] but starting with [PdBr2(cod)]. All other chemicals were ob-
tained commercially and used as received. Melting points were ob-
tained in sealed glass tubes under nitrogen, using a Gallenkamp
melting point apparatus and are uncorrected. A variable-temper-
ature 1H NMR study of the various cationic palladium systems
reported is recorded in the electronic Supporting Information in
addition to ORTEP views for each of the molecular structures de-
termined by X-ray crystallography.
MoϪC(32)
MoϪC(34)
MoϪN(1)
P(1)ϪN(2)
P(1)ϪC(1)
P(2)ϪN(4)
N(1)ϪC(3)
C(2)ϪC(3)
1.940(6)
2.026(5)
2.356(4)
1.687(4)
1.843(4)
1.694(4)
1.287(5)
1.516(5)
MoϪC(31)
MoϪC(33)
MoϪP(1)
P(1)ϪN(3)
P(2)ϪN(5)
P(2)ϪC(2)
C(1)ϪC(3)
1.987(6)
2.052(5)
2.5367(11)
1.692(3)
1.680(4)
1.890(4)
1.497(5)
C(32)ϪMoϪC(31) 87.9(3)
C(31)ϪMoϪC(34) 84.0(3)
C(31)ϪMoϪC(33) 88.4(3)
C(32)ϪMoϪC(34) 84.4(3)
C(32)ϪMoϪC(33) 92.3(2)
C(34)ϪMoϪC(33) 171.8(2)
C(31)ϪMoϪN(1)
C(33)ϪMoϪN(1)
C(31)ϪMoϪP(1)
C(33)ϪMoϪP(1)
N(2)ϪP(1)ϪN(3)
N(3)ϪP(1)ϪC(1)
N(3)ϪP(1)ϪMo
C(32)ϪMoϪN(1)
C(34)ϪMoϪN(1)
C(32)ϪMoϪP(1)
C(34)ϪMoϪP(1)
N(1)ϪMoϪP(1)
N(2)ϪP(1)ϪC(1)
N(2)ϪP(1)ϪMo
C(1)ϪP(1)ϪMo
N(5)ϪP(2)ϪC(2)
C(3)ϪN(1)ϪC(4)
C(4)ϪN(1)ϪMo
C(3)ϪC(2)ϪP(2)
N(1)ϪC(3)ϪC(2)
171.3(2)
93.8(2)
95.8(2)
97.8(2)
75.96(9)
104.0(2)
121.6(2)
100.4(2)
90.5(2)
176.1(2)
90.1(2)
108.2(2)
104.8(2)
118.20(14)
111.7(2)
98.3(2)
121.2(3)
113.5(3)
118.6(3)
115.6(3)
96.70(13) N(5)ϪP(2)ϪN(4)
101.7(2)
117.9(4)
120.9(3)
112.7(2)
125.8(4)
N(4)ϪP(2)ϪC(2)
C(3)ϪN(1)ϪMo
C(3)ϪC(1)ϪP(1)
N(1)ϪC(3)ϪC(1)
C(1)ϪC(3)ϪC(2)
Conclusion
Together, these observations suggest that the easily pre-
pared, chelating P,N-ligand 1 makes an interesting partner
for a range of metals. The straightforward synthesis and
now predictable coordination geometry of bis(phosphanyl)-
Synthesis of [PdCl2(PNP-κ2P,N)] (2): A dichloromethane (10 mL)
solution of 1 (0.32 g, 0.57 mmol) was added to a solution of
[PdCl2(NCPh)2] (0.22 g, 0.57 mmol) in dichloromethane (10 mL)
imine 1 offers considerable scope for further ‘‘tuning’’ the at Ϫ30 °C. The mixture was allowed to warm to room temp. and
738 Eur. J. Inorg. Chem. 2002, 732Ϫ742

Group 6 and 10 Complexes of iPrNϭC[CH2P(NiPr2)2]2
FULL PAPER
3
stirred for 2 h, affording a red-orange solution. Removal of solvent
under reduced pressure gave a yellow-orange solid that was washed
with Et2O (3 ϫ 10 mL) yielding a pale yellow analytically pure
CH2), 3.90 (m, 4 H, PNCH), 4.08 (sept, 1 H, JH,H ϭ 6.4, Cϭ
NCH). 13C {1H} NMR (75.8 MHz, CDCl3): δ ϭ Ϫ1.7 (d, PdCH3,
3JPC ϭ 9.0), 21.9 [s, CϭNCH(CH3)2], 23.0 [d, JPC ϭ 6.6,
3
3
sample of 2 (0.38 g, 90% yield). Single crystals suitable for study PNCH(CH3)2], 23.2 (d, JPC
ϭ
3.0), 23.5 [d, JPC
ϭ
7.2,
3
by X-ray diffraction were obtained following prolonged cooling PNCH(CH3)2], 24.5 [d, JPC ϭ 3.0, PNCH(CH3)2], 36.4 (dd,
3
2
(Ϫ30 °C) of a concentrated CH2Cl2/Et2O solution, m.p. Ͼ 225 °C
1JPC ϭ 19.2, JPC ϭ 4.5, exocyclic PCH2), 46.1 (d, JPC ϭ 10.8,
2
2
(dec.). C30H67Cl2N5P2Pd (737.16): calcd. C 48.88, H 9.18, N 9.50; PNCH), 47.0 (d, JPC ϭ 9.0, PNCH), 49.2 (dd, JPC ϭ 25.9, 7.2,
found C 49.02, H 9.02, N 9.48. MS (FABϩ, NBA matrix): m/z ϭ
endocyclic PCH2), 54.7 (s, CϭNCH), 170.4 (m, CϭN).
1
702 [M Ϫ Cl]. H NMR (270.1 MHz, CDCl3): δ ϭ 1.08 [d, 12 H,
[PdMe2(PNP-κ2P,N)] (5): To a mixture of [PdMe2(tmeda)] (0.48 g,
1.9 mmol) and 1 (1.07 g, 1.9 mmol) was added dichloromethane (30
mL) at room temp. The yellow reaction mixture was stirred for 48 h
at room temp. before volatile components were removed in vacuo.
The resulting off white solid was washed with Et2O (3 ϫ 10 mL).
Complex 5 was dried under vacuum (1.02 g, 77% yield), m.p. Ͼ
180 °C (dec.). C32H73N5P2Pd (696.46): calcd. C 55.18, H 10.59, N
10.06; found C 49.27, H 10.67, N 10.18. MS (FABϩ, NBA matrix):
m/z ϭ 696 [Mϩ], 682 [Mϩ Ϫ CH2]. 1H NMR (301.5 MHz, CDCl3):
3
3JH,H
ϭ
6.7, PNCH(CH3)2], 1.16 [d, 12 H, JH,H
ϭ
6.7,
3
PNCH(CH3)2], 1.28 [d, 12 H, JH,H ϭ 6.9, PNCH(CH3)2], 1.45 [d,
12 H, JH,H ϭ 6.9, PNCH(CH3)2], 1.65 [d, 6 H, JH,H ϭ 6.7, Cϭ
NCH(CH3)2], 2.94 (s, 2 H, CH2), 3.35 (m, 4 H, PNCH), 3.61 (d, 2
3
3
2
3
H, JPH ϭ 11.6, CH2), 4.07 (sept, 4 H, JH,H ϭ 6.9, PNCH), 4.28
(sept, 1 H, JH,H ϭ 6.7, CϭNCH). 13C {1H} NMR (68.0 MHz,
3
3
CDCl3): δ ϭ 23.1 [s, CϭNCH(CH3)2], 24.4 [d, JCP ϭ 6.2,
3
PNCH(CH3)2], 25.2 [d, JCP ϭ 7.2, PNCH(CH3)2], 25.7 [s,
PNCH(CH3)2], 38.5 (dd, 1JCP ϭ 20.6, 3JCP ϭ 9.8, exocyclic PCH2),
3
3
δ ϭ 0.73 (d, 3 H, JPH ϭ 0.9, PdϪCH3), 1.12 [d, 12 H, JH,H
ϭ
2
2
47.7 (d, JCP ϭ 10.3, PNCH), 50.0 (d, JCP ϭ 7.2, PNCH), 54.4
(dd, JCP ϭ 35.6, JPC ϭ 10.8, endocyclic PCH2), 59.0 (s, Cϭ
6.4, PNCH(CH3)2], 1.22 [d, 12 H, 3JH,H ϭ 6.4, PNCH(CH3)2], 1.31
1
3
3
3
[d, 12 H, JH,H ϭ 6.9, PNCH(CH3)2], 1.34 [d, 12 H, JH,H ϭ 7.1,
PNCH(CH3)2], 1.61 [d, 6 H, 3JH,H ϭ 6.5, CϭNCH(CH3)2], 2.87 (s,
2 H, CH2), 3.33 (dd, 2 H, JPH ϭ 13.7, JPH ϭ 3.8, CH2), 3.40
2
NCH), 176.6 (dd, JCP ϭ 8.3, 16.5, CϭN).
2
4
Synthesis of [PdCl(Me)(PNP-κ2P,N)] (3): A dichloromethane solu-
tion (10 mL) of 1 (0.72 g, 1.28 mmol) was added to a solution of
[PdCl(Me)(cod)] (0.34 g, 1.28 mmol) in dichloromethane (10 mL)
at Ϫ30 °C. The mixture was allowed to warm to room temp. and
stirred for 1 h, affording a red solution. Removal of solvent under
reduced pressure gave a yellow-orange solid that was washed with
Et2O (3 ϫ 10 mL) yielding 3 as a cream powder that was used
without further purification (0.78 g, 85% yield), m.p. Ͼ 200 °C
(dec.). C31H70ClN5P2Pd (716.74): calcd. C 54.64, H 10.38, N 10.28;
found C 55.01, H 10.10, N 10.20. MS (FABϩ, NBA matrix): m/z ϭ
717 [Mϩ], 702 [Mϩ Ϫ Me], 681 [Mϩ Ϫ Cl]. 1H NMR (400.1 MHz,
3
3
(sept, 4 H, JH,H ϭ 6.7, PNCH), 3.94 (sept, 4 H, JH,H ϭ 6.7,
PNCH), 4.12 (sept, 1 H, JH,H ϭ 6.5, CϭNCH). 13C {1H} NMR
3
2
(62.9 MHz, CDCl3): δ ϭ Ϫ0.6 (d, JPC ϭ 7.8, Pd-CH3), 22.7 [s,
3
CϭNCH(CH3)2], 24.3 [d, JPC ϭ 6.6, PNCH(CH3)2], 24.4 [d,
3JPC ϭ 3.0, PNCH(CH3)2], 24.7 [d, 3JPC ϭ 7.2, PNCH(CH3)2], 25.9
3
1
3
[d, JPC ϭ 2.4, PNCH(CH3)2], 37.4 (dd, JPC 19.0, JPC ϭ 5.7,
exocyclic PCH2), 47.3 (d, 2JPC ϭ 11.4, PNCH), 48.1 (d, 2JPC ϭ 9.0,
PNCH), 50.6 (dd, 1JPC ϭ 27.1, 3JPC 8.4, endocyclic PCH2), 55.8 (s,
2
2
CϭNCH), 171.3 (dd, JPC ϭ 16.0, JPC ϭ 5.7, CϭN).
[PtCl(Me)(PNP-κ2P,N)] (6): An NMR tube fitted with a J. Young’s
valve was charged with 1 (71 mg, 0.13 mmol), [PtCl(Me)(cod)]
(45 mg, 0.13 mmol) and CDCl3 (0.5 mL) under nitrogen. After 3 d
3
CDCl3): δ ϭ 0.71 (s, 3 H, PdϪCH3), 1.11 [d, 12 H, JH,H ϭ 6.6,
PNCH(CH3)2], 1.20 [d, 12 H, 3JH,H ϭ 6.7, PNCH(CH3)2], 1.30 [24
H, overlapping d, 3JH,H ϭ 6.7, PNCH(CH3)2], 1.60 [d, 6 H, 3JH,H ϭ
at room temp., no further evolution was observed according to 31
P
2
6.5, CϭNCH(CH3)2], 2.85 (s, 2 H, CH2), 3.31 (dd, 2 H, JPH
ϭ
NMR spectroscopy. Removal of volatile components in vacuo, fol-
lowed by washing with Et2O (2 ϫ 2 mL) afforded a mixture of
both cis and trans isomers of 6 as a white powder (0.10 g, 98%
yield), m.p. Ͼ 230 °C (dec.). C31H70ClN5P2Pt (805.53) calcd. C
46.22, H 8.78, N 8.71; found C 46.24, H 8.73, N 8.68. MS (FABϩ,
NBA matrix): m/z ϭ 805 [Mϩ], 790 [Mϩ Ϫ Me], 770 [Mϩ Ϫ Cl].
1H NMR (301.5 MHz, CDCl3), major isomer 6a only: δ ϭ 0.77 (d,
10.0, 4JPH ϭ 1.5, CH2), 3.39 (septd, 4 H, 3JH,H ϭ 6.7, 3JPH ϭ 11.1,
3
PNCH), 3.92 (sept, 4 H, JH,H ϭ 6.7, PNCH), 4.10 (sept, 1 H,
3JH,H ϭ 6.5, CϭNCH). 13C {1H} NMR (100.6 MHz, CDCl3): δ ϭ
2
0.75 (d, JCP ϭ 7.3, Pd-CH3), 22.9 [s, CϭNCH(CH3)2], 24.9 [d,
3JCP ϭ 7.1, PNCH(CH3)2], 24.4 [d, 3JCP ϭ 6.4, PNCH(CH3)2], 24.6
3
3
[d, JCP ϭ 2.4, PNCH(CH3)2], 26.1 [d, JCP ϭ 2.1, PNCH(CH3)2],
37.3 (dd, 1JCP ϭ 19.7, 3JCP ϭ 5.7, exocyclic PCH2), 46.9 (d, 2JCP ϭ
3
3
3 H, JPH ϭ 2.0, PtϪCH3), 1.12 [d, 12 H, JH,H ϭ 6.7,
PNCH(CH3)2], 1.22 [d, 12 H, JH,H ϭ 6.7, PNCH(CH3)2], 1.31 [d,
2
1
10.9, PNCH), 47.8 (d, JCP ϭ 9.3, PNCH), 50.6 (dd, JCP ϭ 26.5,
3JCP ϭ 7.3, endocyclic PCH2), 56.0 (s, CϭNCH), 171.2 (dd, 2JCP ϭ
5.7, 16.1, CϭN).
3
3
3
12 H, JH,H ϭ 7.0, PNCH(CH3)2], 1.32 [d, 12 H, JH,H ϭ 7.0,
PNCH(CH3)2], 1.64 [d, 6 H, 3JH,H ϭ 6.4, CϭNCH(CH3)2], 2.85 (s,
2
4
2 H, CH2), 3.22 (dd, 2 H, JPH ϭ 12.6, JPH ϭ 1.5, CH2), 3.40
Synthesis of [PdBr(Me)(PNP-κ2P,N)] (4): In a similar manner to
the above, reaction of 1 (0.132 g, 0.24 mmol) in dichloromethane
(25 mL) with a solution of [PdBrMe(cod)] (0.073 g, 0.24 mmol) in
dichloromethane (15 mL) at Ϫ30 °C afforded 4. Recrystallisation
from a mixture of ether and dichloromethane (1:1) and prolonged
cooling to Ϫ30 °C afforded 4 as yellow-orange microcrystals
(0.14 g, 72% yield). A small (50 mg) sample of 4 was recrystallised
a second time using the same combination to afford a microcrystal-
line material that afforded correct elemental analyses, m.p. Ͼ 195
°C (dec.). C31H70BrN5P2Pd (761.32): calcd. C 48.92, H 9.27, N
9.20; found C 48.95, H 9.20, N 9.19. MS (FABϩ, NBA matrix): m/
3
3
(sept, 4 H, JH,H ϭ 6.7, PNCH), 4.03 (sept, 4 H, JH,H ϭ 6.7,
PNCH), 4.63 (sept, 1 H, JH,H ϭ 6.7, CϭNCH). 13C {1H} NMR
3
2
(75. 8 MHz, CDCl3), major isomer 6a only: δ ϭ Ϫ15.4 (d, JPH
ϭ
3
4.8, PtϪCH3), 22.5 [s, CϭNCH(CH3)2], 24.2 [d, JPC ϭ 6.0,
PNCH(CH3)2], 24.5 [d, 3JPC ϭ 3.0, PNCH(CH3)2], 24.7 [d, 3JPC
ϭ
3
7.2, PNCH(CH3)2], 25.7 [d, JPC ϭ 2.4, PNCH(CH3)2], 38.0 (dd,
1JPC ϭ 18.9, JPC ϭ 6.6, exocyclic PCH2), 47.3 (d, JPC ϭ 10.8,
3
2
PNCH), 47.8 (d, 2JPC ϭ 8.4, PNCH), 51.0 (dd, 1JPC ϭ 41.8, 3JPC ϭ
2
9.3, endocyclic PCH2), 57.2 (s, CϭNCH), 173.6 (dd, JPC ϭ 15.1
and 3.6, CϭN).
z ϭ 761 [Mϩ], 747 [Mϩ Ϫ CH2], 681 [Mϩ Ϫ Br]. 1H NMR Synthesis of [PdMe(NCCH3)(PNP-κ2P,N)][PF6] (7): A Schlenk
(301.5 MHz, CDCl3): δ ϭ 0.71 (s, 3 H, PdϪCH3), 1.08 [d, 12 H, tube was charged with 3 (108 mg, 0.15 mmol), NaPF6 (28 mg,
3JH,H ϭ 6.7 Hz, PNCH(CH3)2], 1.18 [d, 12 H, JH,H ϭ 6.7, 0.17 mmol), and CH3CN (15 mL) under nitrogen. After stirring at
3
PNCH(CH3)2], 1.28 [m, 24 H, PNCH(CH3)2], 1.60 [d, 6 H, 3JH,H ϭ room temp. for 3 d, the reaction mixture was filtered and all volatile
6.4, CϭNCH(CH3)2], 2.84 (s, 2 H, CH2), 3.35 (m, 6 H, PNCH and components removed in vacuo to afford 7 as a yellow solid, which
Eur. J. Inorg. Chem. 2002, 732Ϫ742
739

P. W. Dyer et al.
FULL PAPER
3
was dried under high vacuum overnight (115 mg, 91% yield), m.p.
6.91 (4 H, pseudo-t, JH,H ϭ 7.3, p-C6H5), 7.07 (8 H, pseudo-t,
Ͼ 109Ϫ110 °C (dec.). C33H73F6N6P3Pd (867.31) calcd. C 45.70, H 3JH,H ϭ 7.3, m-C6H5), 7.48 (8 H, br. s, o-C6H5). 13C NMR
8.48, N 9.69; found C 45.78, H 8.32, N 9.56. MS (FABϩ, NBA (62.9 MHz, CD3CN): δ ϭ 0.4 (s, PdCH3), 23.9 [d, JPC ϭ 4.1, Cϭ
4
matrix): m/z ϭ 681 [Mϩ Ϫ CH3CN]. IR (KBr disc): ν˜ ϭ 2287 NCH(CH3)2], 24.6 [d, JPC ϭ 3.6, PNCH(CH3)2], 24.9 [d, JPC
ϭ
3
3
1
3
(CϵN), 2313 (CϵN). H NMR (400.1 MHz, CDCl3): δ ϭ 0.50 (s,
6.6, PNCH(CH3)2], 25.3 [d, JPC ϭ 6.6, PNCH(CH3)2], 26.1 [d,
3 H, PdϪCH3), 1.12 [d, 12 H, 3JH,H ϭ 6.6, PNCH(CH3)2], 1.23 [d, 3JPC ϭ 3.1, PNCH(CH3)2], 38.4 (dd, JPC ϭ 20.7, JPC ϭ 6.3, ex-
1
3
12 H, JH,H ϭ 6.8, PNCH(CH3)2], 1.32 [m, 30 H, PNCH(CH3)2 ocyclic PCH2), 48.2 [d, 2JPC ϭ 11.7, PNCH(CH3)2], 49.5 [d, 2JPC ϭ
3
1
3
and CϭNCH(CH3)2], 2.33 (br. s, ν1/2 11 Hz, CH3CN), 2.93 (s, 2 H, 8.6, PNCH(CH3)2], 52.6 (d, JPC ϭ 32.4, JPC ϭ 4.7, endocyclic
2
3
CH2), 3.37 (d, 2 H, JPH ϭ 11.5, CH2), 3.43 (sept, 4 H, JH,H
ϭ
PCH2), 123.2 (s, p-C6H5), 127.0 (m, m-C6H5), 137.1 (s, o-C6H5),
6.6, 4JPH ϭ 1.6, PNCH), 3.86 (sept, 4 H, 3JH,H ϭ 6.8, PNCH), 4.09 165.2 (q, JBC ϭ 49.4, ipso-C6H5).
1
(sept, 1 H, 3JH,H ϭ 6.6, CϭNCH). 13C NMR (62.9 MHz, CD3CN):
Synthesis of [Mo(CO)4(PNP-κ2P,N)] (10): To a cold (Ϫ30 °C) solu-
tion of [Mo(CO)4(pip)2] (0.15 g, 0.41 mmol) in CH2Cl2 (10 mL)
was added dropwise a CH2Cl2 solution (10 mL) of 1 (0.23 g,
0.41 mmol). The solution became brown on warming to room
temp. After stirring for 18 h, the volatile components were removed
under reduced pressure. The resulting solid was dissolved in a min-
imum of CH2Cl2 (ca. 2 mL) and pentane added dropwise until
the solution became turbid. Subsequent recrystallisation at Ϫ30 °C
afforded 10 as yellow-orange single crystals (0.20 g, 64% yield) that
were isolated by filtration, m.p. 172Ϫ174 °C. C34H67N5O4P2Mo
(767.81): calcd. C 53.18, H 8.81, N 9.12; found C 53.23, H 8.53, N
9.12. MS (EI): m/z ϭ 740 [Mϩ Ϫ CO], 712 [Mϩ Ϫ 2 CO]. IR
2
3
δ ϭ 0.3 (d, JPC ϭ 6.6, Pd-CH3), 23.9 [d, JPC ϭ 3.6, Cϭ
3
3
NCH(CH3)2], 24.5 [d, JPC ϭ 3.6, PNCH(CH3)2], 24.9 [d, JPC
ϭ
3
6.6, PNCH(CH3)2], 25.2 [d, JPC ϭ 7.1, PNCH(CH3)2], 26.1 [d,
3JPC ϭ 3.1, PNCH(CH3)2], 39.2 (dd, JPC ϭ 20.3, JPC ϭ 6.6, ex-
1
3
2
2
ocyclic PCH2), 48.2 (d, JPC ϭ 11.7, PNCH), 49.5 (d, JPC ϭ 8.1,
PNCH), 53.4 (dd, JPC ϭ 32.0, JPC 5.1, endocyclic PCH2), 56.1
1
3
3
2
2
(d, JPC ϭ 3.0, CϭNCH), 176.3 (dd, JPC ϭ 13.5, JPC ϭ 4.8, Cϭ
N). 19F (235.3 MHz, CD3CN): δ ϭ Ϫ73.3 (d, JPF ϭ 706.5).
1
Synthesis of [PdMe(NCCH3)(PNP-κ2P,N)][B{3,5-(CF3)2C6H3}4]
(8): To a mixture of 3 (125 mg, 0.14 mmol) and Na[B{3,5-
(CF3)2C6H3}4] (100 mg, 0.14 mmol) was added acetonitrile (20 mL)
at room temp. After 3 d at room temp., the solution was filtered to
eliminate NaCl and the solvent subsequently removed under re-
duced pressure to afford a yellow solid of 8, which was dried under
high vacuum overnight (194 mg, 91% yield), m.p. 57Ϫ60 °C.
C65H85BF24N6P2Pd (1585.35): calcd. C 49.24, H 5.42, N 5.30;
found C 49.16, H 5.50, N 5.26. MS (FABϩ, NBA matrix): m/z ϭ
(Nujol): ν ϭ 2009 (CO), 1897 (CO), 1882 (CO), 1822 (CO). 1H
˜
3
NMR (270.1 MHz, C6D6): δ ϭ 1.01 [d, 12 H, JH,H ϭ 6.4,
PNCH(CH3)2], 1.08 [d, 12 H, 3JH,H ϭ 6.4, PNCH(CH3)2], 1.27 (24
3
H, overlapping d, measurable coupling constants JH,H ϭ 8.2 and
3
7.9 Hz), 1.48 [d, 6 H, JH,H ϭ 6.2, CϭNCH(CH3)2], 2.94 (s, 2 H,
br, CH2), 3.14 (m, 4 H, PNCH), 3.59 (s, 2 H, br, CH2), 4.07 (m, 4
H, PNCH), 4.13 (sept, 1 H, JH,H ϭ 6.4, CϭNCH). 13C NMR
3
681 (Mϩ Ϫ CH3CN). IR (KBr disc): ν ϭ 2288 (CϵN), 2316
˜
3
(100.6 MHz, C6D6): δ ϭ 24.0 [d, JPC ϭ 6.2, PNCH(CH3)2], 24.4
(CϵN). 1H NMR (400.1 MHz, CDCl3): δ ϭ 0.50 (s, 3 H, PdCH3),
3
[d, JPC ϭ 7.0, PNCH(CH3)2], 24.6 (br), 26.1 (s, br), 39.9 (dd,
3
3
1.11 [d, 12 H, JH,H ϭ 6.6, PNCH(CH3)2], 1.23 [d, 12 H, JH,H
ϭ
3JPC ϭ 3.2, JPC ϭ 18.8, exocyclic CH2), 47.3 (d, JPC ϭ 11.1,
1
2
6.6, PNCH(CH3)2], 1.30Ϫ1.37 [m, 30 H, CϭNCH(CH3)2 and
PNCH(CH3)2], 2.23 (s, 3 H, CH3CN), 2.90 (s, 2 H, CH2),
3.39Ϫ3.48 [m, 6 H, PNCH(CH3)2 and CH2], 3.82 [sept, 4 H,
PNCH), 50.3 (d, JPC ϭ 10.7, PNCH), 51.5 (dd, 3JPC ϭ 12.0, JPC
2
1
21.6, endocyclic CH2), 56.2 (s, CϭNCH), 176.1 (overlapping dd,
measurable coupling constants JCP ϭ 10.9 and 11.7 Hz, CϭN),
210.1 (d, JPC ϭ 8.4, CO), 218.5 (d, JPC ϭ 42.9, CO), 221.8 (d,
2
3
3JH,H ϭ 6.6, PNCH(CH3)2], 4.08 [sept, 1 H, JH,H ϭ 6.6, Cϭ
2
2
NCH(CH3)2], 7.54 (s, 4 H, p-C6H3), 7.71 (8 H, o-C6H3). 13C NMR
2JPC ϭ 9.1, CO).
2
(62.9 MHz, CD3CN): δ ϭ 0.3 (d, JPC ϭ 6.2, PdCH3), 23.8 [d,
3
4JPC ϭ 3.5, CϭNCH(CH3)2], 24.5 [d, JPC ϭ 3.5, PNCH(CH3)2],
Preparation of 10 from [Mo(cht)(CO)3]: Toluene (10 mL) was added
to a mixture of 1 (0.20 g, 0.36 mmol) and [Mo(cht)(CO)3] (0.08 g,
0.36 mmol) at room temp. After stirring at room temp. for 2 d, the
reaction mixture was heated to 70 °C for a further 3 d. Complex
3
3
24.8 [d, JPC
ϭ
6.9, PNCH(CH3)2], 25.2 [d, JPC
ϭ
7.6,
3
PNCH(CH3)2], 26.1 [d, JPC ϭ 2.8, PNCH(CH3)2], 39.1 (dd,
1JPC ϭ 20.5, JPC ϭ 6.6 exocyclic PCH2), 48.2 [d, JPC ϭ 11.8,
3
2
2
PNCH(CH3)2], 49.4 [d, JPC ϭ 8.3, PNCH(CH3)2], 53.3 (dd,
10 was observed as the only phosphorus-containing product by 31
P
1JPC ϭ 32.5, JPC ϭ 4.8, endocyclic PCH2), 56.0 [d, JPC ϭ 2.8,
3
3
NMR spectroscopy. Subsequent removal of all volatile components
under reduced pressure afforded a brown waxy solid. Washing with
ether (3 ϫ 10 mL) afforded 10 as an orange-brown solid (0.08 g,
28% yield).
CϭNCH(CH3)2], 124.0 (s, p-C6H3), 127.6 (s, m-C6H3), 130.3 (m,
1
CF3), 136.0 (s, o-C6H3), 163.0 (q, JBC ϭ 49.8, ipso-C6H3), 176.2
2
2
(dd, JPC ϭ 12.9, JPC ϭ 3.8, CϭN). 19F NMR (235.3 MHz,
CD3CN): δ ϭ Ϫ63.8 (s, CF3).
Synthesis of fac-[Cr(CO)3(NCMe)(PNP-κ2P,N)] (11): To a solution
of fac-[Cr(CO)3(NCMe)3] (0.2 g, 0.8 mmol) in toluene (10 mL) was
Synthesis of [PdMe(PNP-κ2P,N)][BPh4] (9): A Schlenk tube was
charged with 3 (0.60 g, 0.84 mmol), NaBPh4 (0.32 g, 0.93 mmol), added a toluene (10 mL) solution of 1 (0.44 g, 0.8 mmol) at Ϫ30
and CH3CN (80 mL) under nitrogen. The resulting suspension was
stirred at room temp. for 3 d and subsequently filtered under nitro-
°C. The solution slowly darkened from yellow to orange/brown
upon stirring at room temp. for 2 d. Removal of solvent in vacuo
gen to give a clear yellow solution. Removal of solvent in vacuo afforded a dark brown waxy solid. The product was extracted into
afforded 9 as a brown/orange solid that was dried under high va- toluene (3 mL) and pentane (ca. 2 mL) added. After cooling at
cuum overnight (0.77 g, 92%), m.p. 100Ϫ102 °C. C55H90BN5P2Pd Ϫ30 °C for 12 h, yellow-orange microcrystals of 11 were isolated
(1000.52): calcd. C 66.02, H 9.07, N 7.00; found C 66.84, H 9.06,
by filtration and dried in vacuo for 4 d, at room temp. (0.12 g, 23%
yield). No reliable analyses could be obtained presumably due to
N 6.75. MS (FABϩ, NBA matrix): m/z ϭ 681 [Mϩ]. 1H NMR
(400.1 MHz, CDCl3): δ ϭ 0.51 (s, 3 H, PdCH3), 1.14 [d, 12 H, subsequent decomposition. MS (FABϩ, NBA matrix): m/z ϭ 639
3
3JH,H
ϭ
6.6, PNCH(CH3)2], 1.25 [d, 12 H, JH,H
ϭ
6.6, [Mϩ Ϫ CH3CN Ϫ 2 CO], 611 [Mϩ Ϫ CH3CN Ϫ 3 CO]. IR (Nujol):
PNCH(CH3)2], 1.33 [m, 30 H, PNCH(CH3)2 and CϭNCH(CH3)2], ν ϭ 1941 (w, CO), 1885 (s, CO), 1821 (s, CO). 1H NMR
˜
2
2.90 (s, 2 H, CH2), 3.36 (d, 2 H, JPH ϭ 11.7, CH2), 3.42 [sept, 4
(270.1 MHz, CDCl3): δ ϭ 1.25 (54H br. m), 2.28 (3 H, br. s,
H, 3JH,H ϭ 6.6, 4JPH ϭ 1.8, PNCH(CH3)2], 3.85 [4 H, sept, 3JH,H ϭ CH3CN), 2.90 (2 H, br. s, CH2), 3.39 (9 H, br. m, PNCH, CH2,
3
6.6, PNCH(CH3)2], 4.07 [sept, 1 H, JH,H ϭ 6.7, CϭNCH(CH3)2];
and CH3CN), 3.97 (4 H, br. m, PNCH), 4.22 (1 H, br. m, Cϭ
Eur. J. Inorg. Chem. 2002, 732Ϫ742
740

Group 6 and 10 Complexes of iPrNϭC[CH2P(NiPr2)2]2
FULL PAPER
[2c]
NCH). 13C NMR (75.8 MHz, CDCl3): δ ϭ 22.6 (br, s, CH3CN),
J. L. Petersen, J. Am. Chem. Soc. 1995, 117, 7696Ϫ7710.
3
A. Huang, J. E. Marcone, K. L. Mason, W. J. Marshall, K. G.
24.0 [br, CϭNCH(CH3)2], 24.2 [br. d, JPC ϭ 6.6, PNCH(CH3)2],
[2d]
Moloy, Organometallics 1997, 16, 3377Ϫ3380.
S. M. Auc-
24.6 [br. d, 3JPC ϭ 6.6, PNCH(CH3)2], 24.9 (br. s), 25.9 (br. s), 39.6
ott, A. M. Z. Slawin, J. D. Woollins, J. Chem. Soc., Dalton
1
2
(br. d, JPC ϭ 21.1, exocyclic CH2), 47.3 (br. d, JPC ϭ 10.8,
[2e]
Trans. 2000, 2559Ϫ2575.
H. Tye, D. Smyth, C. Eldred, M.
2
PNCH), 49.4 (br. d, JPC ϭ 9.0, PNCH), 52.8 (br. m, endocyclic
[2f]
Wills, Chem. Commun. 1997, 1053Ϫ1054.
D. E. C. Cor-
PCH2), 57.3 (br. s, CϭNCH), 127.8 (br. s, CH3CN), 176.3 (br. m,
bridge, Phosphorus: An Outline of Its Chemistry, Biochemistry
and Technology, 5th ed., Elsevier, Amsterdam, 1995, p. 51.
J. M. Brunel, A. Heumann, G. Buono, Angew. Chem. Int. Ed.
2
[2g]
CϭNiPr), 219.5 (br. d, JPC ϭ 14.5, CO), 227.9 (br. s, CO), 229.0
2
(br. d, JPC ϭ 18.1, CO).
[2h]
2000, 39, 1946Ϫ1949.
M. L. Clarke, D. J. Cole-Hamilton,
Reaction of [PdMe2(PNP-κ2P,N)] (5) with dppe: An NMR tube was
charged under nitrogen with 5 (0.01 g, 0.01 mmol), dppe (0.005 g,
0.01 mmol), and dry CDCl3 (0.5 mL). The reaction mixture was
shaken and left to stand at room temp. for 30 min. 31P NMR
(101.3 MHz, CDCl3): δ ϭ ϩ55.7 (PdMe2{dppe}), ϩ53.1 (d, 4JPP ϭ
A. M. Z. Slawin, J. D. Woollins, Chem. Commun. 2000,
[2i]
2065Ϫ2066.
M. R. I. Zubiri, M. L. Clarke, D. F. Foster, D.
J. Cole-Hamilton, A. M. Z. Slawin, J. D. Woollins, J. Chem.
Soc., Dalton Trans. 2001, 969Ϫ971.
[3a] A. M. Z. Slawin, M. B. Smith, J. D. Woollins, J. Chem. Soc.,
[3]
[3b]
4
Dalton Trans. 1996, 1283Ϫ1293.
E. Valls, J. Suades, R.
14.5 Hz, [PNP]), ϩ46.2 (d, JPP ϭ 14.5 Hz, [PNP]).
Mathieu, Organometallics 1999, 18, 5475Ϫ5483. [3c] J. Andrieu,
X-ray Crystallographic Study: Crystal Data for 1: C30H67N5P2,
P. Braunstein, Y. Dusausoy, N. Germani, Inorg. Chem. 1996,
[3d]
35, 7174Ϫ7180. Ϫ
M. J. Baker, M. F. Giles, A. G. Orpen,
M ϭ 559.8, orthorhombic, Pbca (no. 61), a ϭ 17.888(1), b ϭ
3
˚
˚
M. J. Taylor, R. J. Watt, J. Chem. Soc., Chem. Commun. 1995,
197Ϫ198. [3e] M. A. Jalil, S. Fujinami, H. Nishikawa, J. Chem.
Soc., Dalton Trans. 2001, 1091Ϫ1098.
P. Braunstein, M. D. Fryzuk, M. Le Dall, F. Naud, S. J. Rettig,
F. Speiser, J. Chem. Soc., Dalton Trans. 2000, 1067Ϫ1074.
A. Baceiredo, G. Bertand, P. W. Dyer, J. Fawcett, N. Griep-
Raming, O. Guerret, M. J. Hanton, D. R. Russell, A. M. Willi-
amson, New J. Chem. 2001, 25, 591Ϫ596.
E. Lindner, H. A. Mayer, A. Möckel, in: Phosphorus-31NMR
Spectral Properties in Compound Characterization and Struc-
tural Analysis (Eds.: L. D. Quin, J. G. Verkade), VCH, New
York, 1994, p. 215.
A. L. Crumbliss, R. J. Topping, in: Phosphorus-31 NMR Spec-
troscopy in Stereochemical Analysis (Eds.: J. G. Verkade, L. D.
Quin), VCH, Florida, 1987, chapter 15.
18.586(2), c ϭ 21.924(2) A, V ϭ 7289(1) A , Z ϭ 8, Dc
ϭ
1.020 g·cmϪ3, µ(Mo-Kα) ϭ 1.40 cmϪ1, T ϭ 293 K, yellow/white
blocks; 6404 independent measured reflections, F refinement, R1 ϭ
0.028, Rw ϭ 0.029, 2743 independent observed absorption cor-
rected reflections [|Fo| Ͼ 4σ(|Fo|), 2θ Յ 50°], 334 parameters. Crystal
Data for 2: C30H67Cl2N5P2Pd, M ϭ 737.1, monoclinic, P21/c (no.
[4]
[5]
˚
14), a ϭ 14.617(1), b ϭ 15.998(3), c ϭ 18.323(3) A, β ϭ 109.44(1)°,
3
V ϭ 4040(1) A , Z ϭ 4, Dc ϭ 1.212 g·cmϪ3, µ(Cu-Kα) ϭ 58.5 cmϪ1
,
˚
[6]
[7]
T ϭ 293 K, yellow platy needles; 5989 independent reflections, F2
refinement, R1 ϭ 0.066, wR2 ϭ 0.164, 4241 independent observed
absorption corrected reflections [|Fo| Ͼ 4σ(|Fo|), 2θ Յ 120°], 362
parameters. Crystal Data for 10: C34H67MoN5O4P2, M ϭ 767.8,
monoclinic, P21/n (no. 14), a ϭ 13.722(1), b ϭ 17.284(1), c ϭ
3
˚
˚
19.098(2) A, β ϭ 109.19(1)°, V ϭ 4278.0(6) A , Z ϭ 4, Dc
ϭ
[8]
[9]
W. de Graaf, S. Harder, J. Boersma, G. van Koten, J. A. Kan-
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The Nuffield Foundation (Award to Newly Appointed Science Lec-
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