Group 10 Metal Complexes of SPS-Based Pincer Ligands: Syntheses, X-ray Structures, and DFT Calculations

FULL PAPER

Group 10 Metal Complexes of SPS-Based Pincer Ligands: Syntheses, X-ray

Structures, and DFT Calculations

[a]

´

Marjolaine Doux, Nicolas Mezailles, Louis Ricard, and Pascal Le Floch*

Keywords: Phosphorus / S ligands / Donor-acceptor systems / Density functional calculations / Group 10 elements

The 2,6-bis(diphenylphosphanylsulfide)phosphinine (1) re-

acts with water to afford a 1,2-dihydrophosphinine oxide 5

and chloroplatinum 19 complexes of the SPS ligand, featur-

ing a P−Br or P−Cl bond, have also been prepared by re-

featuring a P−H bond. Reaction of 5 with one equivalent of acting 1 with [NiBr₂(DME)] and [Pt(COD)Cl₂], respectively.

[Pd(COD)Cl₂] yields the SPS pincer-based complex 6 with a

P(OH) λ⁵-phosphinine central ligand. Complex 6 has been

Like their palladium congener, both species react with eth-

anol to afford the corresponding P−OEt derivatives 20 [M =

structurally characterized. Two possible mechanisms account Ni] and 21 [M = Pt]. nButyl derivatives of these SPS ligands

for the formation of 5: an intramolecular P−H to P−Pd meta-

thesis or one based on the P=O to POH equilibrium. Meth-

anol, ethanol or diethylamine also react with 1 to afford the

corresponding P(H)(OMe) 7, P(H)(OEt) 8, and P(H)(NEt₂) 9

λ⁵-phosphinines. No definitive mechanism for the formation

of 7−9 can be proposed since no intermediates were detected

also bind to Ni−Br (complex 22) and Pt−Cl (complex 23) frag-

ments. Both complexes were straightforwardly prepared by

reacting anion 3, resulting from the reaction of nBuLi with

1, with the [NiBr₂(DME)] and [Pt(COD)Cl₂] precursors. The

chloride ligand is readily substituted by acetonitrile in com-

plexes 4, 11, 20, and 21 upon treatment with AgBF₄in dichlo-

in situ by ³¹P NMR spectroscopy. However, DFT calculations romethane. Reaction of AgOTf with the palladium complex

(at the B3LYP 6-311+G(d,p) level of theory) suggest that the

conversion of 1,2-dihydrophosphinines into λ⁵-phosphinines

is not viable because it involves a high activation energy.

Like 5, λ⁵-phosphinines 7 and 8 react with [Pd(COD)Cl₂] to

afford the expected palladium complexes 10 and 11. An al-

ternative method relies on the reactivity of nucleophiles with

a SPS pincer-based complex 2 featuring a P−Cl bond. (−)-

Menthol and lithium diethylamide react with 2 to yield the

4 affords complex 28 via substitution of the chloride ligand

by TfO⁻. The X-ray crystal structures of the dimethyl-λ⁵de-

rivative 29 of 1, and that of its P-OMe anion 30, have been

recorded. Anion 30 can be regarded as a phosphanyl-substi-

tuted pentadienyl anion. DFT calculations and a charge de-

composition analysis (CDA) show that the phosphorus atom

in these SPS-pincer structures is a classical tertiary phos-

phane ligand in terms of donation and acceptance.

expected P-OMen 13 and P-NEt₂14 complexes. Both com- ( Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,

plexes have been structurally characterized. Bromonickel 18 Germany, 2003)

Introduction

fur-based ligands are particularly appealing since they can

also be employed in the elaboration of synthetic models of

enzymes.^[8]Mainly, four types of sulfur ligands are used:

classical thioethers,^[9Ϫ12]thiolates,^[13,14]sulfoxides,^[15]in

which coordination occurs through the remaining lone pair

at sulfur, and phosphane sulfides.^[16,17]The latter, though

not yet employed in pincer type structures, have found an

interesting application in the rhodium-catalyzed car-

bonylation of methanol when incorporated in a mixed

PϪPϭS bidentate ligand.^[18,19]

The last decade has seen considerable interest in the syn-

thesis and use of pincer ligands in coordination chemistry

and catalysis, largely due to their particular backbone that

allows not only the meridional encapsulation of transition

metals but also the fine tuning of their coordination be-

havior and electronic capacity by varying the central or an-

cillary ligands. This area, pioneered by Shaw,^[1]has been

thoroughly reviewed recently.^[2Ϫ4]Though early studies

mainly focused on the ubiquitous PCP systems, polyhet-

eroatomic-based pincer ligands featuring N, O, P, and S

atoms have attracted increasing attention because multiple

combinations can be used to build mixed systems.^[5Ϫ7]Sul-

Conversely, phosphane derivatives (probably the most

studied ligands) have essentially been used as peripheral

binding sites in pincer systems. This clearly results from

their tetrahedral geometry that precludes the elaboration of

planar rigid-backbones when the phosphorus atom is the

central ligand. Therefore, the building of pincer systems in-

corporating a planar phosphorus atom as central binding

site is an interesting challenge. Besides their structural inter-

est, such systems exhibit very peculiar electronic properties

that markedly differ from those of classical phosphanes and

[a]

´ ´ ´ ´

Laboratoire ‘‘Heteroelements et Coordination’’, UMR CNRS

´

7653 (DCPH), Departement de Chimie, Ecole Polytechnique,

´

92128 Palaiseau Cedex, France

Fax: (internat.) ϩ33-1-69333990

E-mail: lefloch@poly.polytechnique.fr

Supporting information for this article is available on the

WWW under http://ww w .eurjic.org or from the author.

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DOI: 10.1002/ejic.200300303

Eur. J. Inorg. Chem. 2003, 3878Ϫ3894

Group 10 Metal Complexes of SPS-Based Pincer Ligands

FULL PAPER

nitrogen analogs. Indeed, phosphorus in multiple bonds es- Results and Discussion

sentially behaves as a relatively poor σ-donor ligand but

displays a powerful π-accepting capacity.^[20]Very different

systems, incorporating phosphaalkene (P analogs of al-

kenes) or heterocycles, can be anticipated but, in practice,

only aromatic phosphorus heterocycles are sufficiently

stable.

Two routes that exploit the high electrophilicity of the

phosphorus atom in 1 have already been designed for the

synthesis of these SPS palladium complexes. In exploring

the reactivity of 1 toward nucleophiles, we found that reac-

tion with water readily afforded the 1,2-dihydrophosphinine

oxide 5 (Scheme 2). This is a common transformation for

non-kinetically stabilized phosphaalkenes, but not, usually,

for λ³-phosphinines in which the PϭC double bond is

thermodynamically stabilized.^[23,24]However, the presence

of strong acceptor groups at the α position of phosphorus

(C2 and C6) sometimes provokes a significant dearomatiz-

ation of the ring.^[25]Interestingly, only one diastereomer of

5 was formed. The mechanism leading to 5 is discussed be-

low.

We thus recently launched a program aimed at incorpor-

ating phosphinines (phosphorus analogs of pyridines) in

pincer-type structures. Our initial work focused on the syn-

thesis of mixed S-P-S ligands featuring a phosphinine as

central unit and two phosphane sulfides as ancillary li-

gands. Such systems proved to be easily available in large

amounts by sulfurization of the corresponding 2,6-bis(di-

phenylphosphanyl)-λ³-phosphinines. However, the highly

electropositive phosphorus atoms are particularly reactive

towards nucleophilic attack. Thus the reaction of ligand 1

with [Pd(COD)Cl₂] afforded a complex 2 featuring a central

(λ⁵-σ⁴) pentavalent tetracoordinate phosphorus atom.^[21]

This new type of palladium complex, which can be derivat-

ized by nucleophilic displacement of the chlorine atom at

phosphorus, is particularly stable. Recently, we devised a

much more rational approach to these complexes through

the reaction of 1-R-1-P-phosphahexadienyl anions with

[Pd(COD)Cl₂]. Thus, anion 3, which is readily obtained by

reacting nBuLi with phosphinine 1, reacted with

[Pd(COD)Cl₂] to afford complex 4 (Scheme 1). The latter

proved to be particularly active (TON up to 10000) in the

Miyaura-catalyzed cross-coupling process that allows the

synthesis of aromatic boronic esters from halo aromatic

and dialkoxyboranes.^[22]

Scheme 2

The structure of 5, fully characterized by NMR spec-

troscopy and elemental analysis, was confirmed by an X-

ray crystal structure study. It shows no particular features

and is not presented here.^[26]Interestingly, 5 could also be

used as

a source of [Pd(SPSOH)Cl] (6) [SPS ϭ

C₅H(Ph₂PS)₂P] upon reaction with [Pd(COD)Cl₂]

(Scheme 3).

Scheme 3

1

Complex 6 was characterized by ³¹P and H NMR as

well as by elemental data but was too insoluble to be

characterized by ¹³C NMR spectroscopy. Fortunately, suit-

able crystals for an X-ray crystal analysis could be grown

by diffusing hexanes into a chloroform solution of the com-

plex. A view of one molecule of 6 and the most significant

metric parameters (Figure 1), and crystal data and struc-

tural refinement details (Table 6), are presented here. Com-

plex 6 adopts a distorted planar geometry around the pal-

ladium atom and the two sulfides act as ancillary ligands.

The most interesting data are the internal metric param-

eters within the SPS ligand. As previously noted for the nBu

Scheme 1

As this chemistry might be extended to other metal cen- derivative 4, the phosphorus atom and the C3 carbon atom

ters, we aimed to expand the synthesis of this new type of escape from the plane defined by the C1ϪC2ϪC4 and C5

phosphorus ligand and their applications in coordination atoms by 19.0° and 4.8°, respectively, to yield a boat-like

chemistry and catalysis. We report here the synthesis of conformation. Though the pyramidality of the phosphorus

group 10 metal complexes. Different synthetic methodolog- atom (316.5°) compares with that of classical tertiary phos-

˚

ies, the X-ray structures of some complexes as well as a phanes, the PϪC1 [1.757(4) A] and PϪC5 [1.767(4) A] bond

preliminary theoretical study of their electronic properties lengths are very short. At first sight, these data suggest that

are reported.

the ylidic character of the λ⁵-phosphinine has been pre-

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FULL PAPER

served upon coordination. Another intriguing piece of data

is the bond lengths within the two ancillary PϭS ligands.

Indeed, whereas the two external PϪC bond lengths [e.g.

˚

P3ϪC5 ϭ 1.776(4) A] are also very short compared to

classical PϪC single bonds, the two PϭS bonds are length-

˚

ened [e.g. P2ϪS1 ϭ 2.039(2) A] compared with classical

uncoordinated and coordinated phosphane sulfides. For ex-

ample, in [Pd(R₃PϭS)] complexes the PϭS bond length

usually falls between 1.9823(17), 2.0089(18) and 2.0237(9)

[27Ϫ29]

˚

A.

The concomitant lengthening of this PϪS bond

with the shortening of the external PϪC bond suggests

there is delocalization within the unsaturated ligand back-

bone. Theoretical calculations to clarify this point will be

presented below. The structure of 6 shows no other particu-

lar features.

Scheme 4

Compound 1 also reacted with primary alcohols and sec-

ondary amines to afford the corresponding λ⁵-phosphinines

that formally result from the insertion of the phosphorus

atom lone pair into the AϪH bond (A ϭ RO or R₂N).

Whereas the reactions with methanol and ethanol to give 7

and 8 are rather slow and need excess ROH to go to com-

pletion, diethylamine readily reacts with 1 to form com-

pound 9. These derivatives are the first examples of λ⁵-pho-

sphinines featuring a PϪH bond.^[22,33]Both compounds

were fully characterized by NMR and mass spectroscopy,

as well as by elemental analysis for 7 (Scheme 5). Only pri-

mary alcohols react with 1 and additional experiments with

menthol and phenol led to the recovery of 1, even under

forcing conditions (heating, high concentration of reagents).

In ³¹P NMR, the formation of 7, 8, and 9 was evidenced

by the presence of two magnetically equivalent PPh₂S

groups. The presence of a PϪH bond was definitively estab-

Figure 1. ORTEP view of complex 6. Atoms are drawn as 50%

thermal ellipsoids. Phenyl groups are omitted for clarity. The num-

bering is arbitrary and different from that used in the NMR spec-

˚

troscopic data. Selected bond lengths [A]: P1ϪC1 1.757(4), C1ϪC2

1.420(5), C2ϪC3 1.391(5), C3ϪC4 1.407(5), C4ϪC5 1.384(5),

C5ϪP1 1.767(4), P1ϪO1.597(4), P2ϪC1, 1.759(4), P2ϪS1

2.039(2), P3ϪC5 1.776(4), P3ϪS2 2.1018(2), P1ϪPd1 2.186(1),

S1ϪPd1 2.310(1), S2ϪPd1 2.353(1), Pd1ϪCl1 2.405(1); selected

bond and dihedral angles [°]: C1ϪP1ϪC5 102.7(2), P1ϪC1ϪC2

117.5(3), C1ϪC2ϪC3 122.2(4), C2ϪC3ϪC4 125.2(4), C3ϪC4ϪC5

122.6(4), C4ϪC5ϪP1 119.3(3), P1ϪPd1ϪCl1 174.66(4),

S1ϪPd1ϪS2 174.67(4), (mean plane C1ϪC2ϪC4ϪC5)ϪP1 19.0,

(mean plane C1ϪC2ϪC4ϪC5)ϪC3 4.8. Σangles at P1 316.5

1

lished in the H NMR spectrum by a strong J(P-H) coup-

ling constant (619.0 Hz in 7, 613.0 Hz in 8 and 545.0 Hz

in 9).

It is relatively difficult to propose a definitive mechanism

to account for the formation of 6 from 5. Indeed, ³¹P NMR

monitoring of the reaction revealed only signals corre-

sponding to 5 and 6. Two possible mechanisms leading to 6

can be proposed, both of which are promoted by the initial

displacement of the COD ligand by the two ancillary phos-

phane sulfide groups to yield an intermediary PdCl₂com-

plex. In the first mechanism, the close proximity of the

PϪH and PdϪCl bond leads to dehydrochlorination to

yield HCl and a metallated 1,2-dihydrophosphinine oxide;

the last step can be regarded as a (1,3) shift of hydrogen

Scheme 5

The formation of λ⁵-phosphinines by the direct conden-

from the C2 carbon atom to the PϭO bond (Scheme 4). sation of alcohols and amines with phosphinines is unpre-

The second mechanism relies on the phosphane cedented and emphasizes the reactivity of 1. In most of the

oxideϪhydroxyphosphane tautomerism. Thus, displace- several synthetic approaches towards λ⁵-phosphinines they

ment of one chloride ligand by the phosphorus atom lone are obtained directly by trapping the 1-R-1-P-phospha-

pair would yield a cationic complex that could further un- hexadienyl anions with electrophiles. Indeed, these anions

dergo a dehydrochlorination. Such metal-promoted PϭO to are ambident and display two sites of attack, the lone pair

POH or PϭS to PϪSH rearrangements have been used to at phosphorus and the Cα and Cγ carbon atoms of the

prepare palladium-phosphinous or palladium phosphino- carbocyclic backbone. ‘‘Soft electrophiles’’ (MeI for ex-

thious acid complexes, and in CϪP coupling.^[30Ϫ32]

ample) react at the phosphorus atom whereas ‘‘hard electro-

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Group 10 Metal Complexes of SPS-Based Pincer Ligands

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philes’’ (such as H^ϩ) tend to react at the anionic part of the (E_A) (from 50.442 kcal/mol for R ϭ OMe to 66.393 kcal/

ring to afford 1,2-dihydrophosphinines.^[34Ϫ36]This is prob- mol for R ϭ H) (Scheme 8). To assess the influence of the

ably why λ⁵-phosphinines featuring a PH bond have never substitution pattern of the ring, calculations were per-

been synthesized before (Scheme 6).

formed on a model compound featuring two PPH₂S at the

α-positions and a methoxy group at phosphorus. However,

as in Cα-unsubstituted derivatives, a high activation barrier

(44.848 kcal/mol) is required to form the corresponding λ⁵-

phosphinine (Scheme 9).

Scheme 6

However, λ⁵-phosphinines are supposed intermediates in

the thermolysis of 1,2-dihydrophosphinines to produce

phosphinines. This transformation, which involves a (1,2)

shift of the R group from the Cα carbon atom to phos-

phorus (Scheme 7) followed by an elimination of AH, usu-

ally occurs at high temperature and is well docu-

mented.^[34,37]

Scheme 8

Scheme 9

Scheme 7

Though no intermediates could be detected during our

experiments, we first supposed that the reaction of MeOH

and Et₂NH initially produces transient 1,2-dihydrophosphi-

nines that can further isomerize to yield the corresponding

λ⁵derivatives. No theoretical data are available on this iso-

merization. To clarify this point, DFT calculations were

carried out using the combination of the B3LYP functional

with the 6-311ϩG(d,p) basis set. We first focused on the

rearrangement of Cα-unsubstituted compounds derived

from the parent phosphinine (compounds Ia, b, c, d). The

relative energies show that the 1,2-dihydro derivative are the

most stable isomers (Table 1). Substitution of alkyl groups

by OMe or NH₂groups tends to reduce the energetic differ-

ence. This is in good agreement with previous theoretical

calculations, which showed that the introduction of an elec-

tronegative atom on phosphorus slightly increases the aro-

maticity of the ring by negative hyperconjugation.^[38]How-

ever, whatever the substituent at phosphorus, conversions

of the 1,2-dihydrophosphinines into the corresponding λ⁵-

compounds (IIa, b, c, d) require a high activation energy

This short theoretical investigation clearly shows that the

introduction of two diphosphanylsulfide groups at the Cα

position of phosphorus does not significantly modify the

reaction pathway. Therefore, at this stage, no definitive

mechanism can be proposed. However, we believe that this

transformation is promoted by an initial attack of the oxy-

gen or nitrogen atom at the phosphorus, the two ancillary

PPh₂S groups assisting, in a second step, the transfer of H^ϩ

to phosphorus (Scheme 10). Further calculations to localize

a possible transition state as well as a complete study on

the transformation of λ⁵and dihydrophosphinines into

phosphinines are currently underway and will be reported

in due course. Very probably, a similar mechanism takes

place between 1 and H₂O in the formation of 5 via a transi-

ent λ⁵-phosphinine. Indeed, λ⁵-phosphinines featuring a

PϪOH group rapidly isomerize to the corresponding 1,2-

dihydrophosphinine oxide derivatives.^[39]

Table 1. Relative energies (ZPE corrected) in kcal/mol of model

compounds I, II, and their corresponding TS

I

TS

II

Scheme 10

Ia

Ib

Ic

Id

Ie

0

TSa

TSb

TSc

TSd

TSe

ϩ66.393

ϩ62.475

ϩ50.442

ϩ57.760

ϩ44.848

IIa

IIb

IIc

IId

IIe

ϩ18.235

ϩ11.790

ϩ1.892

ϩ6.874

ϩ0.245

Interestingly, compounds 7, 8 can also be used as precur-

sors for the synthesis of P-alkoxy-substituted PdCl com-

plexes. Thus when 7, 8 were treated with [Pd(COD)Cl₂] in

THF at room temperature, complexes 10 and 11 were cle-

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Scheme 11

Figure 2. ORTEP view of complex 13. Atoms are drawn as 50%

thermal ellipsoids. The numbering is arbitrary and different from

that used in the NMR spectroscopic data; selected bond lengths

anly formed in good yields (Scheme 11). Complex 10 has

previously been obtained by a nucleophilic substitution of

the PϪCl complex. Complex 10 and 11 were identified by

NMR techniques and elemental analyses.

˚

[A]: P1ϪC1 1.761(3), C1ϪC2 1.408(4), C2ϪC3 1.389(4), C3ϪC4

1.409(4), C4ϪC5 1.407(4), C5ϪP1 1.751(3), P1ϪPd1 2.188(1),

C1ϪP2 1.778(3), P2ϪS1 2.033(2), C5ϪP3 1.774(3), P3ϪS2

2.033(2), P1ϪO1 1.600(2), S1ϪPd1 2.328(1), S2ϪPd1 2.313(1),

Pd1ϪCl1 2.396(1). Selected angles and dihedral angles [°]:

P1ϪC1ϪC2 118.2(2), C1ϪC2ϪC3 122.0(3), C2ϪC3ϪC4 125.7(3),

C3ϪC4ϪC5 121.2(3), C4ϪC5ϪP1 118.6(2), P1ϪPd1ϪCl1

170.11(3), S1ϪPd1ϪS2 172.98(3). C4ϪC2ϪC1ϪP1 20.0,

C1ϪC5ϪC4ϪC3 5.2, (mean plane C1ϪC2ϪC4ϪC5)ϪP1 20.9,

(mean plane C1ϪC2ϪC4ϪC5)ϪC3 5.5. Σangles at P1 313.3

The synthesis of an amino derivative proved to be much

more difficult to handle because of the concomitant release

of HCl. For example, reaction of 9 with [Pd(COD)Cl₂] in

THF at room temperature afforded the poorly soluble salt

12. The formulation of 12 was established on the basis of

1

its H NMR spectrum, which reveals an acidic proton at

parameters (Figure 2), and crystal data and structural re-

finement details (Table 6), are given. This route was also

efficient for the synthesis of the amino derivative 14. Reac-

tion of Et₂NLi with 2 in THF at low temperature cleanly

afforded 14 which was recovered as a yellow solid in nearly

quantitative yield (Scheme 13).

δ(CD₃COCD₃) ϭ 9.25 ppm, and elemental analyses. The

formation of 12 could not be prevented even in the presence

of a large excess of diethylamine as HCl scavenger.

Since no intermediates could be detected in ³¹P NMR

spectroscopy during the synthesis of 10 and 11, no defini-

tive mechanism can be proposed. However, a mechanism

close to that proposed for the synthesis of complex 6 seems

plausible. In a first step, the COD ligand is displaced from

palladium by the two ancillary sulfide ligands and an elim-

ination of HCl takes place to form the PϪPd bond

(Scheme 12).

Scheme 13

The structure of 14 was confirmed by an X-ray analysis.

An ORTEP view of one molecule of 14 (Figure 3), and crys-

tal data and structural refinement details (Table 7), are

given. The structure of 14 does not significantly differ from

Scheme 12

Alkoxy complexes can also be obtained by the classical that of 5. The two internal PϪC bond lengths [P1ϪC1

˚

route that relies on the displacement of the Cl atom from 1.756(2) A and P1ϪC5 1.763(2) A] as well as the external

˚

phosphorus by ROH in complex 2. Thus, complex 13 was ones [C1ϪP2 1.766(2) A and C5ϪP3 1.762(2) A] are also

easily obtained by treating (Ϫ)-menthol with 2 in dichloro- short, and the two PϪS bond lengths [P2ϪS1 2.029(1) A

methane at room temperature. The formation of 13 was evi- and P3ϪS2 2.033(1) A] are long.

˚

denced by an ABC spin system pattern in ³¹P NMR spec-

Our investigations on potential precursors of these pal-

trum Ϫ a result of the chiral group introduced at phos- ladium() complexes have yielded another approach to P-

phorus, which renders the two ancillary PPh₂S substituents alkyl derivatives. Reaction of anion 15 with C₂Cl₆afforded

magnetically non-equivalent (see Exp. Sect.). The formu- the λ⁵-phosphinine 16 featuring a PϪCl bond (Scheme 14).

lation of 13 was confirmed by an X-ray structural study. A This compound, isolated as a moisture-sensitive solid, was

view of one molecule of 13 and the most significant metric successfully characterized by NMR and mass spectroscopy.

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Group 10 Metal Complexes of SPS-Based Pincer Ligands

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Figure 3. ORTEP view of complex 14. Atoms are drawn as 50%

thermal ellipsoids. The numbering is arbitrary and different from

that used in the NMR spectroscopic data; selected bond lengths

˚

[A]: P1ϪC1 1.756(2), C1ϪC2 1.409(3), C2ϪC3 1.408(3), C3ϪC4

1.400(3), C4ϪC5 1.411(3), C5ϪP1 1.763(2), P1ϪN1 1.681(2),

P2ϪC1 1.766(2), P2ϪS1 2.029(1), C5ϪP3 1.762(2), P3ϪS2

2.033(1), P1ϪPd1 2.186(1), S1ϪPd 2.3250(8), S2ϪPd 2.3275(8),

Pd1ϪCl1 2.404(1). Selected angles and dihedral angles [°]:

C1ϪP1ϪC5 103.3(1), P1ϪC1ϪC2 117.0(2), C1ϪC2ϪC3 122.3(2),

C2ϪC3ϪC4 125.3(2), C3ϪC4ϪC5 122.2(2), C4ϪC5ϪP1 117.3(2),

P1ϪPd1ϪCl1 167.07(2), S1ϪPdϪS2 171.42(2), (mean plane

C1ϪC2ϪC4ϪC5)ϪP1 20.6, (mean plane C1ϪC2ϪC4ϪC5)ϪC3

5.75. Σangles at P1 314.1

Scheme 15

complexes 18 and 19 respectively (Scheme 15). The PϪBr

18 and PϪCl 19 derivatives, which are moisture sensitive,

were characterized by ³¹P NMR spectroscopy and by X-

ray diffraction studies. However their structures, which are

similar to that of the PdϪCl complex 2, are not reported

here. As with the palladium derivative the PϪBr and PϪCl

bonds are sufficiently reactive to undergo nucleophilic sub-

stitution. Thus, reaction of EtOH with 18 and 19 cleanly

afforded complexes 20 and 21, respectively, which were fully

characterized by NMR and mass spectroscopy as well by

elemental analysis. Under standard conditions, intermedi-

ates 18 and 19 need not be isolated (Scheme 15).

Nickel and platinum complexes of alkyl derivatives were

also prepared using the anionic approach. Phosphinine 1

reacted with nBuLi in THF at low temperature to produce

anion 3 which was subsequently treated with [NiBr₂(DME)]

and [Pt(COD)Cl₂] to yield complexes 22 and 23, respec-

tively (Scheme 16). The NMR spectroscopic data of 22 and

23 are comparable to those of their palladium analog 4.

Scheme 14

Interestingly, 16 reacts with the [Pd(dba)₂] complex to form

complex 17 (Scheme 14), which can be rationalized follow-

ing a classical mechanism that involves the insertion of pal-

ladium into the PϪCl bond of 16. Practically, this route is

probably less straightforward than the direct reaction of

anion 15 with [Pd(COD)Cl₂]. (Scheme 1) However, it shows

that zerovalent metal centers can readily be inserted into

the PϪCl bond of λ⁵-phosphinines. This strategy could be

particularly useful when divalent metal precursors are not

available.

Scheme 16

We wished to extend our several methods devised to in-

Complex 22 was structurally characterized. An ORTEP

troduce any substituent at the phosphorus to nickel and view of one molecule of 22 and the most significant metric

platinum() derivatives. All the approaches developed with parameters (Figure 4), and crystal data and structural re-

palladium complexes have not yet been systematically ex- finement details (Table 7), are presented here. These data

plored. The original method involving the displacement of reveal that replacement of palladium by nickel does not sig-

a chloride atom from the metal to the phosphorus atom nificantly modify the λ⁵-phosphinine backbone, and the

could be duplicated with nickel and platinum using same trends are observed. The PϪC bonds (external and

[NiBr₂(DME)]

(DME

ϭ

dimethoxyethane)

and internal) are short and the PϪS bonds are slightly length-

[Pt(COD)Cl₂] as starting precursors. Both reactions took ened. The two angles between the C1ϪC2ϪC4ϪC5 plane

place in dichloromethane at room temperature to afford and the phosphorus atom (21.05°) and the C3 carbon (4.7°)

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FULL PAPER

Figure 5. ORTEP view of phosphinine 1. Ellipsoids are 50% ther-

mal ellipsoids. The numbering is arbitrary and different from that

˚

Figure 4. ORTEP view of complex 22. Atoms are drawn as 50%

thermal ellipsoids. The numbering is arbitrary and different from

that used in the NMR spectroscopic data; selected bond lengths

used in the NMR spectroscopic data; selected bond lengths [A]:

P1ϪC1 1.742(2), P1ϪC5 1.745(2), C1ϪC2 1.409(3), C2ϪC3

1.399(3), C3ϪC4 1.399(3), C4ϪC5 1.417(3), P2ϪC1 1.826(2),

S1ϪP2 1.956(1), P3ϪC5 1.835(2), S2ϪP3 1.9532(8). Selected

angles [°]: C1ϪP1ϪC5 103.9(1), P1ϪC1ϪC2 123.2(2), C1ϪC2ϪC3

121.0(2), C2ϪC3ϪC4 127.9(2), C3ϪC4ϪC5 120.4(2), C4ϪC5ϪP1

123.3(2), P1ϪC1ϪP2 111.8(1), P1ϪC5ϪP3 112.9(1), C1ϪP2ϪS1

˚

[A]: P1ϪC1 1.776(3), C1ϪC2 1.384(5), C2ϪC3 1.412(4), C3ϪC4

1.412(4), C4ϪC5 1.390(5), C5ϪP1 1.778(3), P1ϪNi2 2.111(1),

C1ϪP2 1.768(3), P1ϪC6 1.829(4), P2ϪS1 2.039(2), C5ϪP3

1.761(3), P3ϪS2 2.045(2), P1ϪC6 1.829(4), S1ϪNi2 2.185(1),

S2ϪNi2 2.194(1), Ni2ϪBr1 2.363(1). Selected angles [°]:

P1ϪC1ϪC2 129.4(2), C1ϪC2ϪC3 121.8(3), C2ϪC3ϪC4 124.9(3),

C3ϪC4ϪC5 122.8(3), C4ϪC5ϪP1 118.0(2), P1ϪNi2ϪBr1

112.73(7),

C5ϪP3ϪS2

112.54(8),

(mean

plane

C1ϪC2ϪC4ϪC5)ϪP1 4.1, (mean plane C1ϪC2ϪC4ϪC5)ϪC3 3.7

163.89(3),

S1ϪNi2ϪS2

172.57(4).

(mean

plane

C1ϪC2ϪC4ϪC5)ϪP1 21.05, (mean plane C1ϪC2ϪC4ϪC5)ϪC3

4.7. Σangles at P1 315.3

cant structural comparison, three compounds were crys-

tallized and submitted to X-ray crystal structure analysis,

the phosphinine precursor 1, the free anionic ligand 15 and

the λ⁵-dimethylphosphinine 29. Phosphinine 1 was easily

crystallized by diffusion of hexanes into a solution of 1 in

CH₂Cl₂. An ORTEP view of one molecule of 1 and the

most relevant metric parameters (Figure 5), and crystal

data and structural refinement details (Table 5), are pre-

sented.

Compound 29 was prepared conventionally with the sub-

sequent trapping of anion 15 with methyl iodide. As ex-

plained above, in good agreement with literature data, the

alkylation takes place exclusively at the phosphorus atom

lone pair to yield 29 in very good yields (Scheme 18). The

formulation of 29 was easily established on the basis of

NMR spectroscopic data and combustion analysis. Suitable

crystals were obtained by diffusion of hexanes into a solu-

tion of 29 in CDCl₃. An ORTEP view of one molecule of

29 and the most significant metric parameters (Figure 6),

and crystal data and structural refinement details (Table 5),

are given.

atom also compare with those of 5, 13 and 14 as well as

the pyramidality of the phosphorus atom.

Finally, a preliminary study of the reactivity of the hal-

ogen ligand in these complexes showed that the chloride

(Pd and Pt) or bromide ligand (Ni) is easily abstracted upon

reaction with AgBF₄in dichloromethane at room tempera-

ture in the presence of acetonitrile (Scheme 17). Four cat-

ionic complexes 24Ϫ27 were thus obtained and fully

characterized by NMR techniques and elemental analyses.

Interestingly, reaction of the palladium complex 4 with Ag-

OTf furnished the neutral complex 28. Its formulation was

unambiguously established on the basis of NMR spectro-

scopic data and elemental analysis.

Having developed several new synthetic pathways to

these d⁸metal complexes, we turned our attention to the

electronic structure of the SPS pincer ligands. As noted ear-

lier, some X-ray structural data suggest that electronic de-

localization occurs within the ligand. To establish a signifi-

The crystallization of an anionic derivative of 1 proved

to be much more difficult. To draw a precise comparison

with the dimethyl-λ⁵-phosphinine 29, the crystallization of

anion 15 was attempted. However, whatever the experimen-

tal conditions used (solvent, temperature, presence or ab-

sence of cryptand) no suitable crystals could be grown.

However, crystallization of the methoxy-substituted species

30 gave more satisfying results. Anion 30 was readily pre-

pared by reacting 3 equivalents of MeONa with 1 in THF

at room temperature (Scheme 19). Suitable crystals of this

anion were obtained upon crystallization with the (2.2.2)

cryptand. An ORTEP view of one molecule of 30 and the

most relevant bond lengths and bond angles (Figure 7), and

crystal data and structural refinement details (Table 5), are

presented.

Scheme 17

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Group 10 Metal Complexes of SPS-Based Pincer Ligands

FULL PAPER

Scheme 18

The structural data of 1, 29, and 30 provide interesting

information. The structure of ligand 1 is relatively classical

and compares with those of other λ³-phosphinines. The two

internal PϭC bond lengths and the CϪC bond lengths

within the ring fall in the usual range and the ring is planar.

The two sulfide groups point towards the back of the mol-

ecule to minimize the electronic repulsion between the lone

pair at phosphorus and that of sulfur atoms (Figure 5). Of

most interest is the external PϪC bond lengths [C1ϪP2

˚

1.826(2) A and C5ϪP3 1.835(2) A], which compare with

those of classical PϪC single bonds. Moreover, the PϭS

Figure 6. ORTEP view of phosphinine 29. Ellipsoids are 50% ther-

mal ellipsoids. The numbering is arbitrary and different from that

˚

bond lengths [P2ϪS1 1.956(1) A and P3ϪS2 1.953(1) A]

are normal. Transformation of 1 into 29 obviously induces

important distortions and the phosphorus atom now es-

capes, by 23.15°, from the C1ϪC2ϪC4 and C5 plane. While

the ylidic structure of the ring is evidenced by a small

lengthening of the internal PϪC bonds, the two external

used in the NMR spectroscopic data; selected bond lengths [A]:

P1ϪC1 1.767(2), P1ϪC5 1.768(2), C1ϪC2 1.410(2), 1.410(2),

C2ϪC3 1.402(2), C3ϪC4 1.411(2), C4ϪC5 1.404(2), P1ϪC6

1.799(2), P2ϪC1 1.789(2), S1ϪP2 1.9675(8). Selected angles [°]:

C1ϪP1ϪC5 106.25(8), P1ϪC1ϪC2 112.3(1), C1ϪC2ϪC3

123.1(2), C2ϪC3ϪC4 126.6(2), C3ϪC4ϪC5 122.7(2), C4ϪC5ϪP1

113.0(1), P1ϪC1ϪP2 120.9(1), P1ϪC5ϪP3 119.2(1), C1ϪP2ϪS1

114.24(7),

C4ϪP3ϪS2

113.36(7),

(mean

plane

˚

C1ϪC2ϪC4ϪC5)ϪP1 37.0, (mean plane C1ϪC2ϪC4ϪC5)ϪC3 ones are slightly shortened [1.789(2) A and 1.792(2) A], sug-

17.0

gesting that a delocalization occurs. However, this delocaliz-

ation is probably weak and does not extend to the two PϭS

bonds due to the orientation of the two phosphane-sulfides

groups, which are not coplanar with the unsaturated part

of the ring. This effect is also apparent in 30, which consists

of two discrete units of the anionic ligand and [Na(2.2.2)].

Though the substituent at phosphorus is different (Me in

29, OMe in 30), the introduction of the charge significantly

modifies the hybridization state of the phosphorus atom.

Scheme 19

˚

Thus, in 30 the two internal PϪC bond lengths [1.802(4) A

˚

and 1.791(5) A] have lost their ylidic character and this

anion can be considered as a simple phosphanyl-substituted

pentadienyl anion.^[40]Note also that, as in 29, the two exter-

˚

nal PϪC bond lengths [1.794(5) A and 1.770(4) A] are also

quite short.

These data do not obviously compare with those of the

Pd and Ni complexes, and it is relatively difficult to estab-

lish whether the ligand behaves as an anionic λ⁴-phosphin-

ine (form A) or as a classical tertiary phosphane (form B).

The short internal PϪC bond lengths suggest that the ylidic

structure of the phosphinine has been restored upon com-

plexation but, conversely, the relatively long PϪS bonds and

short external PϪC connections point to delocalization

within the unsaturated part of the ligand (form B)

(Scheme 20).

Figure 7. ORTEP view of anion 30. Ellipsoids are 50% thermal

ellipsoids. The numbering is arbitrary and different from that used

˚

in the NMR spectroscopic data; selected bond lengths [A]: P1ϪC1

1.802(4), C1ϪC2 1.390(7), C2ϪC3 1.408(7), C3ϪC4 1.393(6),

C5ϪC5 1.406(7), C5ϪP1 1.791(5), C5ϪP1 1.791(5), C1ϪP2

1.794(5), C5ϪP3 1.770(4), P3ϪS2 1.974(2), P2ϪS1 1.968(2),

P1ϪO1 1.661(4). Selected angles and dihedral angles [°]:

C5ϪP1ϪC1 105.0(2), P1ϪC1ϪC2 121.5(3), C1ϪC2ϪC3 122.6(4),

C2ϪC3ϪC4 125.4(4), C3ϪC4ϪC5 121.4(4), C4ϪC5ϪP1 122.2(3),

P1ϪC5ϪP3 116.4(3), P1ϪC1ϪP2 115.9(3), (mean plane

C1ϪC2ϪC4ϪC5)ϪP1 21.0, (mean plane C1ϪC2ϪC4ϪC5)ϪC3

6.0

Scheme 20

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M. Doux, N. Mezailles, L. Ricard, P. Le Floch

FULL PAPER

Reasonably, one may propose that both forms can con-

tribute to the bonding, the respective contributions being

determined by the nature of the metal centre and its formal

oxidation state. Lacking a wide range of complexes and X-

ray structures, it seems premature to propose a definitive

model to rationalize the bonding in these complexes. A pre-

liminary theoretical study aimed at evaluating the electronic

capacity of the ligand in these group 10 complexes was thus

undertaken. Optimizations were carried out on the two

model complexes IIIa, b featuring a methyl group and a

methoxy group at phosphorus, respectively (Scheme 21).

Table 2. Most significant geometrical data for calculated structures

IIIa, b, IVa, b, and V. Distances [A] and angles [°]

˚

IIIa

IIIb

IVa

IVb

V

P1ϪC2

C2ϪC3

C3ϪC4

C2-P2

P2ϪS1

P1ϪR

1.796

1.395

1.404

1.768

2.050

1.846

2.258

2.377

101.7

1.780

1.397

1.403

1.774

2.049

1.650

2.243

2.377

101.5

1.881

1.882

1.843

1.856

1.859

1.829

1.834

2.300

2.322

107.4

1.612

2.275

2.323

106.6

1.836

2.302

2.324

108.0

P1ϪPd

Pd1ϪCl

The ligand substitution scheme was simplified to save com- C6ϪP1ϪC2

putation time, and phenyl groups of the phosphane sulfide

substituents, as well as those located on the phosphinine

phosphane-based complexes IVa, b and V. These data also

suggest that the PϪPd bond is slightly more polarized in

IIIa, b than in IVa, b and V, but these differences are not

very significant. Care must be taken in drawing rapid con-

clusion from charge distributions, especially in transition

metal complexes.

ring, were replaced by hydrogen atoms (Scheme 21).

Table 3. Calculated NBO charge distribution for ligands IIe, f, and

complexes IIIa, b and V

IIe

IIIa

IIIb

IVa

IVb

V

Scheme 21

P1

1.662

1.170

1.420

1.038

1.375

1.060

C2 Ϫ0.950 Ϫ0.922 Ϫ0.942 Ϫ1.123 Ϫ1.156 Ϫ0.744

C3 Ϫ0.136 Ϫ0.139 Ϫ0.151

Various functional and basis sets were tested. The best

compromise, in terms of computation time and accuracy of

structural data, was a combination of the B3LYP functional

with a mixed basis set composed of the 6-31G* basis set for

C, H, O, P, S and Cl atoms and the effective core potentials

(ECP) of Hay and Wadt for Pd. The most significant bond

lengths and bond angles of IIIa, b (Table 2) show an accept-

C4 Ϫ0.326 Ϫ0.350 Ϫ0.334

P2

S

Pd

Cl

0.880

Ϫ0.563 Ϫ0.457 Ϫ0.398 Ϫ0.302 Ϫ0.293 Ϫ0.308

0.351 0.367 0.313 0.310 0.323

0.921

0.917

0.850

0.846

0.856

Ϫ0.576 Ϫ0.560 Ϫ0.433 Ϫ0.437 Ϫ0.440

To determine which form (A or B) is preponderant in the

able fit between theoretical and experimental parameters. bonding to the metal, a charge decomposition analysis was

Thus, the same trend is seen for PϪC (internal and exter- carried out using the CDA program developed by Frenking

nal) and PϪS bond lengths. For example in IIIa, the in- and coll. Such analysis has proved to be very useful in esti-

˚

ternal PϪC bonds (1.796 A) are close to that in the nBu mating the ratio between donation and back-donation for

˚

derivative [1.762(7) A] whose structure was previously re- ligands following the classical DewarϪChattϪDuncansson

ported. In IIIb, the external PϪC bonds are shortened (DCD) model. Further explanations about the method, the

˚

(1.774 A vs 1.778(3) A in 13) and the PϪS bonds are length- terms used in these calculations and their relevance are

˚

ened (2.049 A vs. 2.033(2) A in 13). The only discrepancies given in the theoretical section. Complexes IIIa, b were

arise from the PϪPd and SϪPd bond lengths and from the compared to the virtual cationic complexes IVa, b, and V

dihedral angle measuring the out-of-plane distortion of the featuring a tertiary phosphane as central ligand and two

phosphorus atom. Indeed, PϪPd and SϪPd bond lengths peripheral phosphane sulfide groups. Complex V only dif-

are overestimated and the out-of-plane distortion is under- fers from IVa by the presence of two exocyclic CH₂groups

estimated in the theoretical structures. However, modifi- which mimic the unsaturated backbone of the phosphinine

cation of the basis set for Pd (all electron-basis sets, other ring.

ECP, diffuse functions) or phosphorus and sulfur (diffuse

functions) did not significantly improve data.

The results of the CDA analysis are presented in Table 4.

A first important remark concerns the residual term (∆)

An analysis of natural charge (NBO method) reveals which allows one to consider the interaction in terms of

that, in IIIa, b, the phosphorus atom bears a significant donorϪacceptor behavior. All of the complexes exhibit a

positive charge and that the α (C2 and C6) and γ (C4) car- low (∆) value, indicating that their bonding to Pd can be

bon atoms are negatively charged (Table 3). Conversely, the described following the DCD model. The second interesting

β (C3 and C5) carbon atoms are positively charged. This point concerns the b/(dϩb) value which reflects the percent-

charge distribution is relatively equivalent to that observed age of π-acceptance. The similarity of these values clearly

in λ⁵-phosphinines (see for example data for IIe). However, indicates that the central phosphorus atom in IIIa, b (15.19

a relatively similar charge distribution is observed in the and 19.23%) exhibits electronic properties that are close to

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Group 10 Metal Complexes of SPS-Based Pincer Ligands

FULL PAPER

m, multiplet; v, virtual; b, broad. Mass spectra were obtained at

70 eV with a HP 5989B spectrometer coupled to a HP 5980 chrom-

atograph by the direct inlet method. Elemental analyses were per-

formed by the ‘‘Service dЈanalyse du CNRS’’, at Gif sur Yvette,

France. Phosphinine 1 and complex 2,^[21]anion 3 and complex 4,^[22]

Table 4. Charge decomposition analysis of complexes IIIa, b, IVa,

b, and V

IIIa

IIIb

IVa

IVb

V

d^[a]

1.089

0.195

5.58

0.844

0.201

4.20

0.855

0.171

5.00

0.935

0.160

5.843

0.863 [Ni(dme)Br₂],^[41]

0.147

5.87

[Pd(COD)Cl₂],^[42]

[Pd(dba)₂],^[43]

and

b^[b]

[Pt(COD)Cl₂]^[44]were prepared according to reported procedures.

d/b

Phosphinine 1: Suitable crystals for X-ray structure analysis were

grown by diffusion of hexanes into a solution of 1 in CH₂Cl₂.

b/(dϩb)

15.19

Ϫ0.397

Ϫ0.008

19.23

Ϫ0.076

Ϫ0.005

16.66

0.069

Ϫ0.001

14.62

Ϫ0.092

0.025

14.55

Ϫ0.093

0.004

r^[c]

∆

Phosphane Oxide 5: Water (0.1 ml) was added to a solution of 1

(370 mg, 0.54 mmol) in THF (20 mL). The reaction was then

stirred for 5 min at room temperature and the solvent was removed

under vacuum. The solid was washed with diethyl ether (2 ϫ 5 mL)

and, after drying, 5 was recovered as a yellow powder. Suitable

crystals for X-ray structure analysis were grown from a diffusion

those of classical tertiary phosphane complexes IV and V

(between 14.55 and 16.66%). Note that the exocyclic double

bonds in V do not significantly modify the electronic ca-

pacity of the ligand. Overall, we therefore propose that, at

least in the case of d⁸palladium complexes, the delocalized

form B is probably preponderant.

1

of hexanes into a solution of 5 in CH₂Cl₂.Yield: 97%, 366 mg. H

NMR (300 MHz, CDCl₃, 298 K): δ ϭ 5.05 [ABBЈX, td, ²J(H-

2

3

P_A) ϭ J(H-P_B) ϭ 16.6, J(HϪH) ϭ 2.1, 1 H, H²], 6.55 (ABBЈX,

m, ΣJϭ 9, 1 H, H⁴), 6.74 [dd, J(H-P_A) ϭ 580, J(HϪH) ϭ 2.7, 1

H, PH], 6.82Ϫ8.20 (m, 30 H, CH of Ph) ppm. ¹³C NMR

(75.5 MHz, CDCl₃, 298 K): δ ϭ 43.5 (m, C²H), 119.9 (m, C⁶),

127.7Ϫ133.4 (m, C⁴H, CH and C of Ph), 137.4 (ABBЈX, m, ΣJϭ

20, C^{5 or 3}), 140.5 (ABBЈX, m, ΣJϭ 21, C^{3 or 5}), 163.4 [d, ³J(C-

P_A) ϭ 3.7, C of Ph] ppm. ³¹P NMR (121.5 MHz, CDCl₃, 298 K):

δ ϭ 4.22 [ABBЈ, dd, ²J(P_A-P_B) ϭ 35.3, ²J(P_A-P_BЈ) ϭ 17.0, P_AH],

36.47 [ABBЈ, d, J(P_A-P_B) ϭ 35.3, P_BPh₂], 38.92 [ABBЈ, d, J(P_A-

P_BЈ) ϭ 17.0, P_BЈPh₂] ppm. MS (EI): m/z ϭ 682 [M^ϩϪ (H₂O)].

C₄₁H₃₃OP₃S₂(698.75): calcd. C 70.47, H 4.76; found C 70.03, H

4.34.

1

3

Conclusion

We have presented several unusual routes towards λ⁵-

phosphinines derivatives of the 2,6-bis(diphenylphosphan-

yl)phosphinine. Easy access towards previously unknown

PϪH derivatives and a straightforward preparation of a

PϪCl derivative have also been devised. Additionally, new

synthetic approaches towards SPS-λ⁵phosphinine group 10

metal complexes have been developed using either these

PϪH, PϪCl derivatives or a 1,2-dihydrophosphinine oxide.

Most of these routes should be operative with other metal

halides. Structural data as well as a preliminary theoretical

investigation suggests that a delocalization takes place

within the carbocyclic part of the ligand but that the central

phosphorus atom behaves as a classical tertiary phosphane.

Further studies will now focus on the catalytic properties

of the group 10 complexes and on a systematic investigation

of the coordinative properties of SPS based-ligands. A de-

tailed theoretical study of their electronic properties will be

reported elsewhere.

2

Complex 6: A solution of [Pd(COD)Cl₂] (155 mg, 0.54 mmol) and

5 (380 mg, 0.54 mmol) in CH₂Cl₂(10 mL) was stirred for 2 h at

room temperature. After removing the solvent under vacuum, the

resultant yellow solid was washed with hexanes (3 ϫ 5 mL) and

dried. Suitable crystals for an X-ray structure analysis were grown

from a diffusion of hexanes into a solution of CDCl₃. Yield: 83%,

376 mg. ¹H NMR (300 MHz, CDCl₃, 298 K): δ ϭ 5.83 (m, 1 H,

H⁴), 6.60Ϫ7.60 (m, 30 H, CH of Ph) ppm. ³¹P NMR (121.5 MHz,

CDCl₃, 298 K): δ ϭ 54.36 [AB₂, d, ²J(P_A-P_B) ϭ 105.7, P_BPh₂],

90.10 [AB₂, t, ²J(P_A-P_B) ϭ 105.7, P_A] ppm. Complex 6 was too

insoluble to

a give a

satisfactory ¹³C NMR spectrum.

C₄₁H₃₂ClOP₃PdS₂(839.62): calcd. C 58.65, H 3.84; found C 58.28,

H 3.47.

λ⁵-Phosphinine 7: A solution of 1 (100 mg, 0.15 mmol) and meth-

anol (200 µL, 4.9 mmol) in THF (5 mL) was stirred for 24 h at 40

°C. After removing the solvent under vacuum, the resultant yellow

solid was washed first with hexanes (3 ϫ 2 mL) and then with di-

ethyl ether (3 ϫ 2 mL). After drying, 7 was recovered as a yellow

powder in 73% (78 mg) yield. ¹H NMR (300 MHz, CD₂Cl₂,

298 K): δ ϭ 3.38 (d, J_HϪPϭ 13.8, 3 H, CH₃), 5.7 [td, J(H-P_B) ϭ

3.8, ⁴J(H-P_A) ϭ 1.7, 1 H, H⁴], 7.56 [dt, ¹J(H-P_A) ϭ 619.0, ³J(H-

P_B) ϭ 1.9, 1 H, PH], 6.80Ϫ7.76 (m, 30 H, CH of Ph) ppm. ¹³C

NMR (75.5 MHz, CD₂Cl₂, 298 K): δ ϭ 49.5 (br. s, CH₃), 80.7 (m,

C^2,6), 116.3 (m, C⁴H), 125.8Ϫ133.5 (m, CH and C of Ph), 140.5

[m, ΣJ(C-P) ϭ 20.7, C^3,5], 156.4 (s, C of Ph) ppm. ³¹P NMR

(121.5 MHz, CD₂Cl₂, 298 K): δ ϭ 27.57 [AB₂, t, ²J(P_A-P_B) ϭ 43.7,

P_A], 39.46 [AB₂, d, ²J(P_A-P_B) ϭ 43.7, P_B] ppm. MS (EI): m/z ϭ 682

[M^ϩϪ (MeOH)]. C₄₂H₃₅OP₃S₂(712.78): calcd. C 70.77, H 4.95;

found C 70.31, H 4.44.

Experimental Section

General Remarks: All reactions were routinely performed under an

inert atmosphere of argon or nitrogen using Schlenk and glove-box

techniques and dry deoxygenated solvents. Dry THF and hexanes

were obtained by distillation from Na/benzophenone and dry di-

ethyl ether from CaCl₂and then NaH and dry CH₂Cl₂from P₂O₅.

Acetonitrile (99.5% purity) was purchased from SDS and used

without further purification. CDCl₃was dried over P₂O₅, and

3

4

˚

stored on 4A Linde molecular sieves. CD₂Cl₂, [D₈]THF, and [D₆]a-

cetone were used as purchased and stored in the glove-box. Nuclear

magnetic resonance spectra were recorded on a Bruker AC-200 SY

spectrometer operating at 300.0 MHz for ¹H, 75.5 MHz for ¹³C

and 121.5 MHz for ³¹P. Solvent peaks were used as internal refer-

ence relative to Me₄Si for ¹H and ¹³C chemical shifts (ppm); ³¹P

chemical shifts are relative to an 85% H₃PO₄external reference.

λ⁵-Phosphinine 8: A solution of 1 (550 mg, 0.8 mmol) and ethanol

Coupling constants are given in Hertz. The following abbreviations (200 µL, 3.4 mmol) in THF (5 mL) was stirred for 24 h at 40 °C.

are used: s, singlet; d, doublet; t, triplet; q, quadruplet; p, pentuplet; After removing the solvent under vacuum, the resultant solid was

Eur. J. Inorg. Chem. 2003, 3878Ϫ3894

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3887

´

M. Doux, N. Mezailles, L. Ricard, P. Le Floch

FULL PAPER

washed first with hexanes (3 ϫ 2 mL) and then with diethyl ether

Pd Complex 12: A mixture of [Pd(COD)Cl₂] (37.9 mg, 0.13 mmol)

(3 ϫ 2 mL). After drying, 8 was recovered as a yellow powder in and λ⁵-phosphinine 9 (100 mg, 0.13 mmol) in CH₂Cl₂(5 mL) was

78% (433 mg) yield. ¹H NMR (300 MHz, CD₂Cl₂, 298 K): δ ϭ 1.26 stirred for 30 min at room temperature. The so-obtained yellow

3

[t, J(HϪH) ϭ 7.2, 3 H, CH₃], 3.90 [dq, J(HϪH) ϭ J(H-P_A) ϭ precipitate was washed first with hexanes (3 ϫ 2 mL) and then with

7.2, 2 H, CH₂], 5.72 [t, ⁴J(H-P_B) ϭ 7.2, 1 H, H⁴], 6.84Ϫ7.76 (m,

diethyl ether (3 ϫ 2 mL). After drying, complex 12 (114 mg) was

30 H, CH of Ph), 7.73 [d, J(H-P_A) ϭ 613.0, 1 H, PH] ppm. ¹³C recovered as a yellow solid in 90% yield . ¹H NMR (300 MHz,

1

3

NMR (75.5 MHz, CD₂Cl₂, 298 K): δ ϭ 15.1 [d, J(C-P_A) ϭ 16.0,

CH₃], 63.3 [d, ²J(C-P_A) ϭ 6.9, CH₂O], 81.7 [ddd, ¹J(C-P_A) ϭ 101.2, ³J(H-P_A) ϭ ³J(HϪH) ϭ 6.3, 4 H, CH₂], 5.84 [dt, ³J(H-P_A) ϭ ³J(H-

¹J(C-P_B) 80.5, ³J(C-P_BЈ) 4.6, C^2,6], 117.2 (m, C⁴H), P_B) ϭ 3.5, 1 H, H⁴], 6.66Ϫ7.70 (m, 30 H, CH of Ph), 9.25 (br. s, 1

[D₆]acetone, 298 K): δ ϭ 1.27 [t, J_H,Hϭ 6.3, 6 H, CH₃], 2.95 [dq,

ϭ

127.1Ϫ132.2 (m, CH of Ph), 133.5 [dd, ¹J(C-P_B) ϭ 11.5, ³J(C- H, NH) ppm. ³¹P NMR (121.5 MHz, CH₂Cl₂, 298 K): δ ϭ 49.32

P_A) ϭ 3.5, C of Ph], 134.7 [dd, J(C-P_B) ϭ 13.8, J(C-P_A) ϭ 3.4, [AB₂, d, ²J(P_A-P_B) ϭ 100.1, P_BPh₂], 82.18 [AB₂, t, ²J(P_A-P_B) ϭ

1

3

of Ph], 141.5 [dt, ²J(C-P_A) ϭ 11.5, ²J(C-P_B) ϭ ⁴J(C-P_BЈ) ϭ 3.4, 100.1, P_A]. 12 was too insoluble to give a satisfactory ¹³C NMR

C^3,5], 156.3 (s, C of Ph) ppm. ³¹P NMR (121.5 MHz, CD₂Cl₂, spectrum. C₄₅H₄₂Cl₂NP₃PdS₂(931.20): calcd. C 58.04, H 4.55;

2

298 K): δ ϭ 25.87 [AB₂X, t, J(P_A-P_B) ϭ 43.1, P_A], 39.46 [AB₂, d,

²J(P_A-P_B) ϭ 43.1, P_B] ppm. MS (EI): m/z ϭ 682 [M^ϩϪ (EtOH)].

C₄₃H₃₇OP₃S₂(726.81): calcd. C 71.06, H 5.13; found C 70.67, H

4.82.

found C 57.91, H 4.37.

Pd Complex 13:

A

mixture of 1 (300 mg, 0.44 mmol) and

[Pd(COD)Cl₂] (125 mg, 0.44 mmol) in CH₂Cl₂(10 mL) was stirred

for 15 min at room temperature. Menthol (6.9 mg, 0.44 mmol) was

then added to the solution, which was stirred for a further hour at

room temperature and then filtered through celite. After evapor-

ation of the solvent, the resultant solid was washed first with hex-

anes (3 ϫ 2 mL) and then with diethyl ether (3 ϫ 2 mL). After

drying, complex 13 was recovered as a yellow solid. Suitable crys-

tals for X-ray structure analysis were grown by diffusion of hexanes

into a solution of 13 in CH₂Cl₂. Yield 94%, 404 mg. ¹H NMR

(300 MHz, CD₂Cl₂, 298 K): δ ϭ 0.75 [d, ³J(HϪH) ϭ 7.1, 3 H,

CH₃], 0.87 [d, ³J(HϪH) ϭ 6.2, 3 H, CH₃], 0.95 [d, ³J(HϪH) ϭ

6.8, 3 H, CH₃], 1.08Ϫ1.75 (m, 8 H, CH and CH₂), 2.57 [d,

²J(HϪH) ϭ 13.4, 1 H, CH₂], 4.78Ϫ4.87 (m, 1 H, OMen), 5.65 [t,

⁴J(H-P_B) ϭ 4.3, 1 H, H⁴], 6.64Ϫ7.60 (m, 30 H, CH of Ph) ppm.

¹³C NMR (75.5 MHz, CD₂Cl₂, 298 K): δ ϭ 16.7 (s, CH₃), 20.4 (s,

CH₃), 21.2 (s, CH₃), 22.4 (s, CH₂), 24.4 (s, CH), 31.3 (s, CH), 33.6

(s, CH₂), 44.2 (s, CH₂), 48.9 [d, ³J(C-P_A) ϭ 6.6, OϪCHϪCH], 77.2

[d, ¹J(C-P_A) ϭ 6.4, O-CH], 116.6 [AB₂X, q, ⁴J(C-P_A) ϭ ⁴J(C-P_B) ϭ

10.7, C⁴H], 127.0Ϫ128.2 (m, CH of Ph), 130.1 [dd, ¹J(C-P_B) ϭ

λ⁵-Phosphinine 9: A solution of 1 (100 mg, 0.15 mmol) and diethyl-

amine (200 µL, 1.9 mmol) in CH₂Cl₂(5 mL) was stirred for 15 min

at room temperature. After removing the solvent under vacuum,

the so-obtained yellow solid was washed first with hexanes (3 ϫ

2 mL) and then with diethyl ether (3 ϫ 2 mL). After drying, 9

1

(98 mg) was recovered as a yellow powder in 87% yield. H NMR

(300 MHz, CDCl₃, 298 K): δ ϭ 1.14 [t, ³J(HϪH) ϭ 6.9, 6 H, CH₃],

3

2.92 [q, J(HϪH) ϭ 6.9, 4 H, CH₂], 5.59 [t, J(H-P_B) ϭ 4.6, 1 H,

H⁴], 7.29 [dt, ¹J(H-P_A) ϭ 545.0, ¹J(H-P_B) ϭ 2.0, 1 H, PH],

6.76Ϫ7.72 (m, 30 H, CH of Ph) ppm. ¹³C NMR (75.5 MHz,

2

CDCl₃, 298 K): δ ϭ 10.9 (s, CH₃), 41.5 [d, J(C-P_A) ϭ 19.6, CH₂],

87.6 (m, C^2,6), 113.9 [d, ⁴J(C-P_A) ϭ 13.6, C⁴H], 122.6Ϫ131.1 (m,

CH of Ph), 134.5 [d, ¹J(C-P_B) ϭ 84.1, C of Ph], 135.2 [d, ¹J(C-

P_B) ϭ 86.8, C of Ph], 141.4 (m, C^3,5), 155.5 (m, Cq de C₆H₅) ppm.

³¹P NMR (121.5 MHz, CDCl₃, 298 K): δ ϭ Ϫ0.31 [AB₂, t, J(P_A-

2

P_B) ϭ 50.6, P_A], 37.36 [AB₂, d, ²J(P_A-P_B) ϭ 50.6, P_B] ppm. MS

(EI): m/z ϭ 682 [M^ϩϪ (NHEt₂)]. C₄₅H₄₂NP₃S₂(753.88): calcd. C

71.69, H 5.62; found C 41.26, H 5.17.

3

1

3

83.3, J(C-P_A) ϭ 7.6, C of Ph], 130.4 [dd, J(C-P_B) ϭ 84.3, J(C-

P_A) ϭ 7.2, C of Ph], 131.2Ϫ132.1 (m, CH of Ph), 139.2 (m, C^3,5),

155.8 (br. s, C of Ph), 156.4 (br. s, C of Ph). C²and C⁶not ob-

served. ³¹P NMR (121.5 MHz, CD₂Cl₂, 298 K): δ ϭ 47.67 [ABBЈ,

d, ²J(P_A-P_B) ϭ 111.3, P_B], 49.89 [ABBЈ, d, ²J(P_A-P_BЈ) ϭ 104.1, P_BЈ],

Complex 10: A mixture of [Pd(COD)Cl₂] (28 mg, 0.1 mmol) and 7

(71 mg, 0.1 mmol) in THF (10 mL) was stirred for 1 h at room

temperature. After removing the solvent under vacuum, the result-

ant solid was washed first with hexanes (3 ϫ 2 mL) then with di-

ethyl ether (3 ϫ 2 mL). After drying, 10 (78 mg) was recovered as

a yellow solid in 92% yield. For characterization see ref.^[21]

2

88.24 [ABBЈ, dd, J(P_A-P_B) ϭ 111.3, J(P_A-P_BЈ) ϭ 104.1, P_A] ppm.

C₅₁H₅₀ClONP₃PdS₂(977.87): calcd. C 62.64, H 5.15; found C

62.19, H 4.84.

Complex 11: A mixture of [Pd(COD)Cl₂] (28 mg, 0.1 mmol) and 8

Pd Complex 14: A mixture of 1 (100 mg, 0.15 mmol) and

(71 mg, 0.1 mmol) in THF (10 mL) was stirred for 1 h at room [Pd(COD)Cl₂] (42 mg, 0.15 mmol) in THF (5 mL) was stirred for

temperature. After removing the solvent under vacuum, the so-ob- 15 min at room temperature. In a glove-box, Et₂NLi (15 mg,

tained solid was washed first with hexanes (3 ϫ 2 mL) and then

0.19 mmol) was added to the solution which was then stirred for

with diethyl ether (3 ϫ 2 mL). After drying, 11 (76 mg) was reco- 30 min at room temperature. The solvent was subsequently re-

vered as a yellow powder in 78% yield. ¹H NMR (300 MHz,

CD₂Cl₂, 298 K): δ ϭ 1.20 [t, J(HϪH) ϭ 7.0, 3 H, CH₃], 4.30 [dq,

moved under vacuum and the resultant solid washed first with hex-

anes (3 ϫ 2 mL) and then with diethyl ether (3 ϫ 2 mL). After

3

4

3

²J(H-P_A) ϭ 9, J(HϪH) ϭ 7, 2 H, CH₂], 5.47 [t, J(H-P_B) ϭ 7.0, evaporation of the solvent, the resulting solid was dissolved in

1 H, H⁴], 6.68Ϫ7.89 (m, 30 H, CH of Ph) ppm. ¹³C NMR CH₂Cl₂and filtered through celite. After drying, complex 14 was

(75.5 MHz, CD₂Cl₂, 298 K): δ ϭ 17.6 (m, CH₃), 66.0 [d, ²J(C-

recovered as a yellow solid. Suitable crystals for X-ray structure

1

3

P_A) ϭ 4.6, CH₂], 95.9 [ddd, J(C-P_A) ϭ 91, J(C-P_B) ϭ 66.3, J(C- analysis were grown by diffusion of hexanes into a solution of

P_BЈ) ϭ 7.7, C^2,6], 116.1 [q, ⁴J(C-P_A) ϭ ⁴J(C-P_B) ϭ 12.2, C⁴H], CH₂Cl₂. Yield: 89%, 132 mg. ¹H NMR (300 MHz, CD₂Cl₂, 298 K):

128.8Ϫ129.9 (m, CH of Ph), 131.7 [dd, ¹J(C-P_B) ϭ 84.3, ³J(C-

δ ϭ 1.14 [t, ³J(HϪH) ϭ 7.1, 6 H, CH₃], 4.30 [dq, ³J(H-P_A) ϭ 11.3,

P_A) ϭ 8.5, C of Ph], 132.8 [dd, ¹J(C-P_B) ϭ 37.2, ³J(C-P_A) ϭ 3.8, C ⁴J(HϪH) ϭ 7.1, 4 H, CH₂], 5.45 [t, ⁴J(H-P_B) ϭ 4.9, H⁴], 6.71Ϫ7.52

of Ph], 133.2Ϫ133.8 (m, CH of Ph), 141.5 [dt, ²J(C-P_A) ϭ 9.2, ²J(C- (m, 30 H, CH of Ph) ppm. ¹³C NMR (75.5 MHz, CD₂Cl₂, 298 K):

P_B) ϭ ⁴J(C-P_BЈ) ϭ 3.5, C^3,5], 155.5 [d, ³J(C-P_A) ϭ 2.3, C of Ph] δ ϭ 11.1 (s, CH₃), 42.1 (m, CH₂), 89.1 [ddd, ¹J(C-P_A) ϭ 89.0, ¹J(C-

ppm. ³¹P NMR (121.5 MHz, CD₂Cl₂, 298 K): δ ϭ 52.20 [AB₂, d, P_B) ϭ 64.3, ³J(C-P_BЈ) ϭ 7.6, C^2,6], 115.0 [td, ⁴J(C-P_B) ϭ 10.3, ⁴J(C-

²J(P_A-P_B) ϭ 103.0, P_B], 96.24 [AB₂, t, ²J(P_A-P_B) ϭ 103.0, P_A] ppm. P_A) ϭ 2.9, C⁴H], 127.6Ϫ128.8 (m, CH of Ph), 131.6 [dd, ¹J(C-

3

1

C₄₃H₃₆ClOP₃PdS₂(867.67): calcd. C 59.52, H 4.18; found C 59.14,

H 3.79.

P_B) ϭ 78.9, J(C-P_A) ϭ 5.4, C of Ph], 132.4 [dd, J(C-P_B) ϭ 84.3,

³J(C-P_A) ϭ 5.7, C of Ph], 132.1Ϫ132.7 (m, C of Ph), 141.5 [m,

3888

 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

www.eurjic.org

Eur. J. Inorg. Chem. 2003, 3878Ϫ3894

Group 10 Metal Complexes of SPS-Based Pincer Ligands

FULL PAPER

Σ²J(C-P) ϭ 14.8, C^3,5], 155.5 (m, C of Ph) ppm. ³¹P NMR Pt Complex 19: A mixture of [Pt(COD)Cl₂] (165 mg, 0.44 mmol)

(121.5 MHz, CH₂Cl₂, 298 K): δ ϭ 51.77 [AB₂, d, ²J(P_A-P_B) ϭ

100.0, P_B], 66.46 [AB₂, t, ²J(P_A-P_B)

100.0, P_A] ppm.

and 1 (300 mg, 0.44 mmol) in CH₂Cl₂(10 mL) was stirred for

15 min at room temperature. After evaporation of the solvent, the

ϭ

C₄₅H₄₁ClNP₃PdS₂(894.74): calcd. C 60.41, H 4.62; found C 59.96, resulting solid was washed with hexanes (3 ϫ 2 mL) and then dried

H 4.13.

to afford complex 19 (400 mg) as a yellow powder in 96% yield.

2

³¹P NMR (121.5 MHz, CD₂Cl₂, 298 K): δ ϭ 47.99 [AB₂, d, J(P_A-

Anion 15: A solution of MeLi in Et₂O (1.8 mL, C ϭ 0.16 ,

0.29 mmol) was added by syringe into a solution of 1 (200 mg,

0.29 mmol) in THF (10 mL) at Ϫ78 °C. The solution was then

warmed to room temperature and stirred for 20 min. After drying,

P_B) ϭ 109.1, P_B], 67.10 [AB₂M, td, ¹J(P_A-Pt) ϭ 3860.3, ²J(P_A-P_B) ϭ

109.1, P_A].

Ni Complex 20: A solution of [Ni(dme)Br₂] (136 mg, 0.44 mmol)

and 1 (300 mg, 0.44 mmol) in CH₂Cl₂(10 mL) was stirred for

30 min at room temperature and then ethanol (200 µL, 3.4 mmol)

was added. After stirring for 15 min at room temperature, the sol-

vent was removed under vacuum and the resulting solid was

washed first with hexanes (3 ϫ 2 mL) and then with diethyl ether

(3 ϫ 2 mL). After drying, complex 20 (365 mg) was recovered as a

brown powder in 96% yield. ¹H NMR (300 MHz, CD₂Cl₂, 298 K):

1

15 (206 mg) was recovered as a red solid in 100% yield. H NMR

(300 MHz, [D₈]THF, 298 K): δ ϭ 0.99 [d, ²J(H-P_A) ϭ 3.4, 3 H,

CH₃], 5.13 [t, J(H-P_B) ϭ 4.8, 1 H, H⁴], 6.53Ϫ7.57 (m, 30 H, CH

4

of Ph) ppm. ³¹P NMR (121.5 MHz, [D₈]THF, 298 K): δ ϭ 45.87

[AB₂, d, ²J(P_A-P_B) ϭ 155.5, P_B], Ϫ65.70 [AB₂, t, ²J(P_A-P_B) ϭ

155.5, P_AMe].

λ⁵-Phosphinine 16: A solution of MeLi in Et₂O (1.8 mL, C ϭ 0.16

, 0.29 mmol) was added by syringe into a solution of 1 (200 mg,

0.29 mmol) in THF (10 mL) at Ϫ78 °C. The solution was then

warmed to room temperature and stirred for 20 min. Complete for-

mation of 15 was checked by ³¹P NMR spectroscopy. After cooling

at Ϫ78 °C, C₂Cl₆(69 mg, 0.29 mmol) was added and the resultant

solution was warmed to room temperature and stirred for a further

20 min. After removing the solvent, the solid was washed first with

hexanes (3 ϫ 2 mL) and then with diethyl ether (3 ϫ 2 mL). The

so-obtained solid was then dissolved in CH₂Cl₂and filtered

through celite. After drying, 16 (201 mg) was recovered as a yellow

solid in 95% yield. ¹H NMR (300 MHz, [D₈]THF, 298 K): δ ϭ 2.04

3

δ ϭ 1.27 [d, J(HϪH) ϭ 7.0, CH₃], 4.52 [AB₂X, dq, J(HϪH) ϭ

³J(H-P_A) ϭ 7.2, 2 H, CH₂], 6.73Ϫ7.82 (m, 31 H, H⁴and CH of

Ph) ppm. ¹³C NMR (75.5 MHz, CD₂Cl₂, 298 K): δ ϭ 16.4 [d, ³J(C-

P_A) ϭ 8.0, CH₃], 65.4 [d, ²J(C-P_A) ϭ 4.0, CH₂], 95.9 [m, ΣJ(C-

P) ϭ 158.1, C^2,6], 114.8 [q, ³J(C-P_A) ϭ ³J(C-P_B) ϭ 10.1, C⁴H],

127.6Ϫ132.5 (m, C and CH of Ph), 140.9 [p, ²J(C-P_A) ϭ ²J(C-

P_B) ϭ ⁴J(C-P_BЈ) ϭ 3.4, C^3,5], 154.4 (s, C of Ph) ppm. ³¹P NMR

(121.5 MHz, CD₂Cl₂, 298 K): δ ϭ 58.26 [AB₂, d, ²J(P_A-P_B) ϭ

123.9, P_B], 104.57 [AB₂, t, ²J(P_A-P_B)

ϭ 123.9, P_A] ppm.

C₄₃H₃₆BrNiOP₃S₂(864.40): calcd. C 59.75, H 4.20; found C 59.29,

H 3.80.

2

4

Pt Complex 21: A solution of [Pt(COD)Cl₂] (165 mg, 0.44 mmol)

and 1 (300 mg, 0.44 mmol) in CH₂Cl₂(10 mL) was stirred for

15 min at room temperature and ethanol (200 µL, 3.4 mmol) was

then added. After stirring for a further 15 min at room temperature,

the solvent was removed under vacuum and the resulting solid was

washed first with hexanes (3 ϫ 2 mL) and then with diethyl ether

(3 ϫ 2 mL). After drying, complex 21 (400 mg) was recovered as a

[d, J(H-P_A) ϭ 15.1, 3 H, CH₃], 6.16 [vq, J(H-P_B) ϭ J(H-P_B) ϭ

4.1, 1 H, H⁴], 6.97Ϫ8.15 (m, 30 H, CH of Ph) ppm. ¹³C NMR

1

(75.5 MHz, [D₈]THF, 298 K): δ ϭ 18.6 [d, J(C-P_A) ϭ 67.3, CH₃],

83.8 [dd, J(C-P_A) ϭ 90.9, J(C-P_B) ϭ 83.1, J(C-P_BЈ) ϭ 3.2, C^2,6],

1

3

117.7 [dt, ³J(C-P_A) ϭ 27.8, ³J(C-P_B) ϭ 9.0, C⁴H], 128.5Ϫ138.7 (m,

C and CH of Ph), 143.5 [m, ΣJ(C-P) ϭ 18.3, C^3,5], 157.6 [d, J(C-

3

P) ϭ 5.3, C of Ph] ppm. ³¹P NMR (121.5 MHz, [D₈]THF, 298 K):

δ ϭ 65.62 [AB₂, t, ²J(P_A-P_B) ϭ 42.5, P_A], 35.16 [AB₂, d, ²J(P_A-

P_B) ϭ 42.5, P_B] ppm. MS (EI): m/z ϭ 732 [M^ϩ]. 16 was too moist-

ure sensitive to give satisfactory elemental data.

1

yellow powder in 95% yield. H NMR (300 MHz, CD₂Cl₂, 298 K):

δ ϭ 1.38 [d, ³J(HϪH) ϭ 7.0, CH₃], 4.31 [dq, ³J(H-P_A) ϭ 9.0,

³J(HϪH) ϭ 7.0, 2 H, CH₂], 5.66 [dt, J(H-P_B) ϭ 4.8, J(H-P_A) ϭ

0.8, 1 H, H⁴], 6.69Ϫ7.67 (m, 30 H, CH of Ph) ppm. ¹³C NMR

(75.5 MHz, CD₂Cl₂, 298 K): δ ϭ 16.6 [d, ³J(C-P_A) ϭ 7.3, CH₃],

62.7 [d, ²J(C-P_A) ϭ 5.0, CH₂], 88.8 [ddd, ¹J(C-P_A) ϭ 92.6, ¹J(C-

P_B) ϭ 80.0, ³J(C-P_BЈ) ϭ 5.0, C^2,6], 116.3 [q, ⁴J(C-P_A) ϭ ⁴J(C-P_B) ϭ

12.8, C⁴H], 127.6Ϫ128.8 (m, CH of Ph), 130.7 [dd, ¹J(C-P_B) ϭ

4

Pd Complex 17: A mixture of [Pd(dba)₂] (79 mg, 0.14 mmol) and

16 (100 mg, 0.14 mmol) in CH₂Cl₂(5 mL) was stirred for 30 min

at room temperature. After evaporation of the solvent, the resultant

solid was washed first with hexanes (3 ϫ 2 mL) and then with di-

ethyl ether (3 ϫ 2 mL). After drying, 17 (108 mg) was recovered as

a brown powder in 92% yield. ¹H NMR (300 MHz, CD₂Cl₂,

298 K): δ ϭ 1.88 [d, ²J(H-P_A) ϭ 9.6, 3 H, CH₃], 5.42 [t, ⁴J(H-P_B) ϭ

4.4, 1 H, H⁴], 6.61Ϫ7.47 (m, 30 H, CH of Ph) ppm. ¹³C NMR

(75.5 MHz, CD₂Cl₂, 298 K): δ ϭ 24.3 (m, CH₃), 74.2 [dd, ¹J(C-

P_A) ϭ 97.4, ¹J(C-P_B) ϭ 53.0, C^2,6], 117.7 [m, ΣJ(C-P) ϭ 36.5, C⁴H],

127.6Ϫ132.5 (m, C and CH of Ph), 141.5 [m, ΣJ(C-P) ϭ 23.1, C^3,5],

158.9 (s, C of Ph) ppm. ³¹P NMR (121.5 MHz, CD₂Cl₂, 298 K):

3

1

3

83.9, J(C-P_A) ϭ 5.7, C of Ph], 131.5 [dd, J(C-P_B) ϭ 86.6, J(C-

P_A) ϭ 3.4, C of Ph], 132Ϫ132.8 (m, C of Ph), 140.5 [dt, ²J(C-P_A) ϭ

8.3, J(C-P_B) ϭ J(C-P_BЈ) ϭ 2.9, C^3,5], 155.5 (s, C of Ph) ppm. ³¹P

2

4

2

NMR (121.5 MHz, CD₂Cl₂, 298 K): δ ϭ 48.86 [AB₂M, d, J(P_A-

1

2

P_B) ϭ 98.5, P_B], 65.47 [AB₂M, t, J(P_A-Pt) ϭ 3640.0, J(P_A-P_B) ϭ

98.5, P_A] ppm. C₄₃H₃₆ClOP₃PtS₂(956.33): calcd. C 54.00, H 3.79;

found C 53.64, H 3.48.

Ni Complex 22: A solution of nBuLi in hexanes (0.275 mL, C ϭ 1.6

, 0.44 mmol) was added by syringe into a solution of 1 (300 mg,

0.44 mmol) in THF (10 mL) at Ϫ78 °C. The resultant solution was

then warmed to room temperature and stirred for 20 min. Com-

plete formation of 3 was checked by ³¹P NMR (121.5 MHz, THF,

2

δ ϭ 49.44 [AB₂, m, J(P_A-P_B) ϭ 35.0, P_A], 50.44 [AB₂, m, J(P_A-

P_B) ϭ 35.0, P_B] ppm. C₄₂H₃₄ClP₃PdS₂(837.65): calcd. C 60.22, H

4.09; found C 59.83, H 3.86.

Ni Complex 18: A mixture of [Ni(dme)Br₂] (136 mg, 0.44 mmol)

and 1 (300 mg, 0.44 mmol) in CH₂Cl₂(10 mL) was stirred for 1 h 298 K): δ ϭ 45.80 [AB₂, d, ²J(P-P) ϭ 156.0, P_BPh₂], Ϫ66.20 [AB_2,t,

at 40 °C. After evaporation of the solvent, the resulting solid was

washed with hexanes (3 ϫ 2 mL) and, after drying, complex 18 (136 mg, 0.44 mmol) was added and the solution was warmed to

²J(P_A-P_B) ϭ 156.0, P_A-nBu]. After cooling at Ϫ78 °C, [Ni(dme)Br₂]

(384 mg) was then recovered as a brown powder in 97% yield. ³¹P

room temperature and stirred for 15 min. The solvent was then

NMR (121.5 MHz, CD₂Cl₂, 298 K): δ ϭ 55.92 [AB₂, d, ²J(P_A- removed and the resulting solid was dissolved in CH₂Cl₂(8 mL)

2

P_B) ϭ 137.4, P_BPh₂], 98.52 [AB₂, t, J(P_A-P_B) ϭ 137.4, P_A]. Com-

plex 18 was too moisture sensitive to give satisfactory elemental

data.

and filtered through celite. After evaporating the solvent under vac-

uum, the solid was washed several times with hexanes (3 ϫ 2 mL)

and diethyl ether (3 ϫ 2 mL). After drying, 22 was recovered as a

Eur. J. Inorg. Chem. 2003, 3878Ϫ3894

www.eurjic.org

 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

3889

´

M. Doux, N. Mezailles, L. Ricard, P. Le Floch

FULL PAPER

brown solid. Suitable crystals for X-ray structure analysis were

grown from a diffusion of hexanes into a solution of CH₂Cl₂. Yield:

P_B) ϭ 71.0, ³J(C-P_BЈ) ϭ 7.7, C^2,6], 117.1 [q, ⁴J(C-P_A) ϭ ⁴J(C-P_B) ϭ

12.2, C⁴H], 121.2 (br. s, C of CH₃CN), 127.8 [dd, ¹J(C-P_B) ϭ 84.7,

91%, 350 mg. ¹H NMR (300 MHz, CD₂Cl₂, 298 K): δ ϭ 0.97 [t, ³J(C-P_A) ϭ 7.4, C of Ph], 128.1 [ABX, d, ¹J(C-P_B) ϭ 86.6, C of

³J(H-H) ϭ 7.2, 3 H, CH₃], 1.53 (m, 2 H, CH₂), 2.00 (br. s, 4 H, Ph], 128.1Ϫ134.8 (m, CH of Ph), 139.0 [dt, J(C-P_A) ϭ 9.1, J(C-

2

4

CH₂), 5.38 [t, J(H-P_B) ϭ 4.2, 1 H, H⁴], 6.62Ϫ7.44 (m, 30 H, CH

P_B) ϭ ⁴J(C-P_BЈ) ϭ 3.5, C^3,5], 160.5 (s, C of Ph) ppm. ³¹P NMR

of Ph) ppm. ¹³C NMR (75.5 MHz, CD₂Cl₂, 298 K): δ ϭ 12.8 (s, (121.5 MHz, THF, 298 K): δ ϭ 49.03 [AB₂, d, ²J(P_A-P_B) ϭ 85.5,

3

1

CH₃), 23.2 [d, J(C-P_A) ϭ 13.7, CH₂], 25.2 (s, CH₂), 38.9 [d, J(C-

P_B], 87.81 [AB₂, t, ²J(P_A-P_B)

ϭ

85.5, P_A] ppm.

P_A) ϭ 25.7, CH₂], 72.5 (m, C^2,6), 118.6 (m, C⁴H), 126.7Ϫ132.0 (m, C₄₅H₃₉BF₄NOP₃PdS₂(960.08): calcd. C 56.30, H 4.09; found C

CH and C of C₆H₅), 139.4 [d, J(C-P_A) ϭ 6.8, C^3,5], 158.1 (s, C of 55.84, H 3.75.

2

C₆H₅) ppm. ³¹P NMR (121.5 MHz, THF, 298 K): δ ϭ 57.34Ϫ63.09

Ni Complex 26: Acetonitrile (50 µL, 0.96 mmol) was added to a

mixture of 20 (138 mg, 0.16 mmol) and AgBF₄(37 mg, 0.19 mmol)

in CH₂Cl₂(5 mL), and the resultant solution was stirred for 15 min

at room temperature. The solution was then filtered through celite

and, after drying, 26 was recovered as a brown powder (yield: 92%,

(m, AB₂) ppm. C₄₅H₄₀BrNiP₃S₂(876.45): calcd. C 61.67, H 4.60;

found C 61.31, H 4.24.

Pt Complex 23: A solution of nBuLi in hexanes (0.275 mL, C ϭ 1.6

, 0.44 mmol) was added by syringe into a solution of 1 (300 mg,

0.44 mmol) in THF (10 mL) at Ϫ78 °C. The resultant solution was

then warmed to room temperature and stirred for 20 min. Com-

plete formation of 3 was checked by ³¹P NMR spectroscopy. After

cooling at Ϫ78 °C, [Pt(COD)Cl₂] (165 mg, 0.44 mmol) was added

and the solution was warmed to room temperature and stirred for

15 min. The solvent was then evaporated and the resulting solid

was dissolved in CH₂Cl₂(8 mL) and filtered through celite. After

removing the solvent under vacuum, the solid was washed several

times with hexanes (3 ϫ 2 mL) and diethyl ether (3 ϫ 2 mL), and,

after drying, 23 (392 mg) was recovered as a yellow solid in 92%

yield. ¹H NMR (300 MHz, CD₂Cl₂, 298 K): δ ϭ 1.1Ϫ2.22 (m, 9

H, CH₃and CH₂), 5.60 [br. d, ⁴J(H-P_A) ϭ 2.4, 1 H, H⁴], 6.70Ϫ7.70

(m, 30 H, CH of C₆H₅) ppm. ³¹P NMR (121.5 MHz, THF, 298 K):

1

134 mg). H NMR (300 MHz, CD₂Cl₂, 298 K): δ ϭ 1.20 (br. s, 3

H, CH₃of Et), 2.30 (br. s, 3 H, CH₃of CH₃CN), 4.15 (br. s, 2 H,

CH₂), 5.60 (br. s, 1 H, H⁴), 6.40Ϫ7.80 (m, 30 H, CH of Ph) ppm.

¹³C NMR (75.5 MHz, CD₂Cl₂, 298 K): δ ϭ 7.8 (s, CH₃of

CH₃CN), 15.7 [s, ³J(C-P_A) ϭ 8, CH₃of Et], 64.6 [d, ²J(C-P_A) ϭ

6.9, CH₂], 91.9 (m, C^2,6), 115.1 [q, ⁴J(C-P_A) ϭ ⁴J(C-P_B) ϭ 9.8,

C⁴H], 127.19Ϫ132.4 (m, CH and C of Ph and C of CH₃CN), 139.0

2

[dt, ⁴J(C-P_B) ϭ 8, J(C-P_A) ϭ J(C-P_B) ϭ 4, C^3,5], 156.5 (s, C of

Ph) ppm. ³¹P NMR (121.5 MHz, THF, 298 K): δ ϭ 55.22 [AB₂, d,

²J(P_A-P_B) ϭ 106.3, P_B], 88.79 [AB₂, t, ²J(P_A-P_B) ϭ 106.3, P_A] ppm.

C₄₅H₃₉BF₄NNiOP₃S₂(912.35): calcd. C 59.24, H 4.31; found C

58.79, H 3.92.

2

δ ϭ 21.52 [AB₂M, td, J(P_A-Pt) ϭ 3030.6, J(P_A-P_B) ϭ 81.0, P_A],

46.95 [AB₂M, d, ²J(P_A-P_B) ϭ 87.0, P_B]. 24 was too insoluble in

common solvents to give a satisfactory ¹³C NMR spectrum.

C₄₅H₄₀ClP₃PtS₂(968.38): calcd. C 55.81, H 4.16; found C 55.43,

H 3.75.

Pt Complex 27: Acetonitrile (50 µL, 0.96 mmol) was added to a

mixture of 21 (153 mg, 0.16 mmol) and AgBF₄(37 mg, 0.19 mmol)

in CH₂Cl₂(5 mL). After stirring for 15 min at room temperature,

the solution was filtered through celite. After drying, 27 was reco-

vered as

a

yellow powder (yield: 93%, 156 mg). ¹H NMR

(300 MHz, CD₂Cl₂, 298 K): δ ϭ 1.49 [t, ³J(HϪH) ϭ 7.0, 3 H, CH₃

of Et], 2.37 (s, 3 H, CH₃of CH₃CN), 4.15 [p, ³J(H-P_B) ϭ

³J(HϪH) ϭ 7.0, 2 H, CH₂], 5.97 [t, ⁴J(H-P_B) ϭ 5.1, 1 H, H⁴],

6.75Ϫ7.82 (m, 30 H, CH of Ph) ppm. ¹³C NMR (75.5 MHz,

Pd Complex 24: Acetonitrile (50 µL, 0.96 mmol) was added to a

mixture of 4 (150 mg, 0.17 mmol) and AgBF₄(37 mg, 0.19 mmol)

in CH₂Cl₂(5 mL). The resultant solution was stirred for 15 min at

room temperature and was then filtered through celite. After dry-

ing, 24 (140 mg) was recovered as an orange powder in 85% yield.

¹H NMR (300 MHz, CD₂Cl₂, 298 K): δ ϭ 1.05 [t, ³J(HϪH) ϭ 7.3,

3 H, CH₃of nBu], 1.62 [qt, ³J(HϪH) ϭ 14.6, ³J(HϪH) ϭ 7.3,

CH₂], 2.03 (m, 2 H, CH₂), 2.26 (m, 2 H, CH₂), 2.23 (s, 3 H, CH₃

of CH₃CN), 2.44 (m, 2 H, CH₂), 5.60 [t, ⁴J(H-P_B) ϭ 5.1, 1 H, H⁴],

6.69Ϫ7.89 (m, 30 H, CH of Ph) ppm. ¹³C NMR (75.5 MHz,

CD₂Cl₂, 298 K): δ ϭ 8.6 (s, CH₃of CH₃CN), 13.4 (s, CH₃of nBu),

23.5 [d, ³J(C-P_A) ϭ 17.2, CH₂], 25.7 [d, ²J(C-P_A) ϭ 15.7, CH₂],

45.2 [d, ¹J(C-P_A) ϭ 38.2, CH₂], 71.5 (m, C^2,6), 119.3 (m, C⁴H),

126.2 [d, ²J(C-P_A) ϭ 25.5, C of CH₃CN], 125.2Ϫ134.5 (m, CH and

C of Ph), 138.4 [ABBЈX, dt, ²J(C-P_A) ϭ ²J(C-P_B) ϭ 9.0, ⁴J(C-

P_BЈ) ϭ 3.1, C^3,6], 163 (m, C of Ph) ppm. ³¹P NMR (121.5 MHz,

3

CD₂Cl₂, 298 K): δ ϭ 3.5 (s, CH₃), 16.5 [d, J(C-P_A) ϭ 7.5, CH₃],

65 [d, ²J(C-P_A) ϭ 9.8, CH₂], 84.5 [ddd, ¹J(C-P_A) ϭ 96.8, ¹J(C-

P_B) ϭ 87.2, ³J(C-P_BЈ) ϭ 5.6, C^2,6], 118.5 [q, ⁴J(C-P_A) ϭ ⁴J(C-P_B) ϭ

2.1, C⁴H], 125.0 [d, ²J(C-P_A) ϭ 21.4, C of CH₃CN], 127 [dd, ¹J(C-

P_B) ϭ 91.0, ³J(C-P_A) ϭ 4.1, C of Ph], 128 [dd, ¹J(C-P_B) ϭ 95.7,

³J(C-P_A) ϭ 3.7, C of Ph], 128.1Ϫ134.8 (m, CH of Ph), 139 (m,

C^3,5), 160.5 (s, C of Ph) ppm. ³¹P NMR (121.5 MHz, THF, 298 K):

δ ϭ 48.92 [AB₂M, d, ²J(P_A-P_B) ϭ 80.4, P_B], 54.60 [AB₂M, ptt,

¹J(P_A-Pt)

ϭ

3592.9, ²J(P_A-P_B)

ϭ

75.2, P_A] ppm.

C₄₅H₃₉BF₄NOP₃PtS₂(1048.73): calcd. C 51.54, H 3.75; found C

51.29, H 3.24.

Pd Complex 28: A mixture of 4 (97 mg, 0.11 mmol) and AgOTf

(37 mg, 0.19 mmol) was stirred in CH₂Cl₂(3 mL) for 15 min at

room temperature and filtered through celite. After drying, 28 was

2

THF, 298 K): δ ϭ 49.72 [AB₂, d, J(P_A-P_B) ϭ 69.6, P_BPh₂], 64.61

2

[AB₂, t, J(P_A-P_B) ϭ 69.6, P_A] ppm. C₄₇H₄₃BF₄NP₃PdS₂(972.13):

calcd. C 58.07, H 4.46; found C 57.67, H 4.02.

recovered as

a

red powder (yield: 87%, 95 mg). ¹H NMR

Pd Complex 25: Acetonitrile (50 µL, 0.96 mmol) was added to a

(300 MHz, CD₂Cl₂, 298 K): δ ϭ 1.05 [t, ³J(HϪH) ϭ 6.9, 3 H,

mixture of 11 (148 mg, 0.17 mmol) and AgBF₄(37 mg, 0.19 mmol) CH₃], 1.62 [qt, ³J(HϪH) ϭ 6.9, ³J(HϪH) ϭ 13.8, CH₂], 1.92Ϫ2.06

4

in CH₂Cl₂(5 mL). After stirring for 15 min at room temperature,

the solution was filtered through celite. After drying, 25 (155 mg)

(m, 2 H, CH₂), 2.19Ϫ2.31 (m, 2 H, CH₂), 5.50 [t, J(H-P_B) ϭ 4.7,

1 H, H⁴], 6.68Ϫ7.56 (m, 30 H, CH of Ph) ppm. ¹³C NMR

was recovered as an orange powder in 95% yield. ¹H NMR (75.5 MHz, CD₂Cl₂, 298 K): δ ϭ 13.9 (s, CH₃of nBu), 23.5 [d,

(300 MHz, CD₂Cl₂, 298 K): δ ϭ 1.35 [t, ³J(HϪH) ϭ 7.0, 3 H, CH₃³J(C-P_A) ϭ 2.6, CH₂], 25.5 [d, ²J(C-P_A) ϭ 2.6, CH₂], 38.3 (m, CH₂),

3

of EtO], 2.20 (s, 3 H, CH₃of CH₃CN), 4.22 [dq, J(H-P_A) ϭ 1.2,

71.6 (m, C^2,6), 118.6 [q, ⁴J(C-P_A) ϭ ⁴J(C-P_B) ϭ 10.6, C⁴H],

³J(HϪH) ϭ 7.0, 2 H, CH₂], 5.71 [t, ⁴J(H-P_B) ϭ 4.9, 1 H, H⁴], 127.7Ϫ128.8 (m, CH of Ph), 131.1 [dd, ¹J(C-P_B) ϭ 83.8, ³J(C-

6.69Ϫ7.79 (m, 30 H, CH of Ph) ppm. ¹³C NMR (75.5 MHz,

P_A) ϭ 8.3, C of Ph], 131.9Ϫ133.0 (m, CH of Ph), 139.6 (m, C^3,5),

CD₂Cl₂, 298 K): δ ϭ 2.3 (s, CH₃), 16.2 [d, J(C-P_A) ϭ 8.6, CH₃], 159.5 ppm (m, C of Ph), CF₃not observed. ³¹P NMR (121.5 MHz,

3

66.9 [d, ²J(C-P_A) ϭ 8.1, CH₂], 91.6 [ddd, ¹J(C-P_A) ϭ 93.2, ¹J(C-

THF, 298 K): δ ϭ 49.47 [AB₂, d, ²J(P_A-P_B) ϭ 84.4, P_B], 56.05 [AB₂,

3890

 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

www.eurjic.org

Eur. J. Inorg. Chem. 2003, 3878Ϫ3894

Group 10 Metal Complexes of SPS-Based Pincer Ligands

FULL PAPER

2

t, J(P_A-P_B) ϭ 84.4, P_A] ppm. C₄₆H₄₀F₃O₃P₃PdS₃(993.34): calcd. Anion 30: In a glove-box, a mixture of 1 (150 mg, 0.22 mmol) and

C 55.62, H 4.06; found C 55.43, H 3.86.

MeONa (36 mg, 0.66 mmol) in THF (5 mL) was stirred for 15 min.

After drying, 30 was recovered as a yellow powder. Suitable crystals

for X-ray structure analysis were grown from a diffusion of hexanes

into a solution of THF. ³¹P NMR (121.5 MHz, THF, 298 K): δ ϭ

44.60 [AB₂, d, ²J(P_A-P_B) ϭ 153.2, P_B], 66.55 [AB₂, dd, ²J(P_A-P_B) ϭ

148.4, P_A] ppm. 30 was too moisture sensitive to give satisfactory

elemental data.

λ⁵-Dimethylphosphinine 29: A solution of MeLi in hexanes (275 µL,

C ϭ 1.6 , 0.44 mmol) was added by syringe into a solution of 1

(300 mg, 0.44 mmol) in THF (10 mL) at Ϫ78 °C. The resultant

solution was then warmed to room temperature and stirred for

20 min. Complete formation of 15 was checked by ³¹P NMR

2

(121.5 MHz, THF, 298 K): δ ϭ 44.83 [AB₂, d, J(P_A-P_B) ϭ 156.7,

2

P_B], Ϫ66.52 [AB₂, t, J(P_A-P_B) ϭ 156.7, P_A]. After cooling at Ϫ78

X-ray Crystallographic Study: Crystals of compounds 1 (Table 5),

5, 6, 13 (Table 6), 14, 22 (Table 7), 29 and 30 (Table 5) suitable for

X-ray diffraction were obtained by slow diffusion of hexanes into

a CH₂Cl₂solution for 1, 5, 13, 14, 22, into a CDCl₃solution for

6, 29, and into a THF solution for 30. Data were collected at

150.0(1) K on a Nonius Kappa CCD diffractometer using a Mo-

°C, MeI (50 µL, 0.80 mmol) was added and the solution was

warmed to room temperature and stirred for 15 min. The solvent

was then evaporated and the resulting solid was dissolved in

CH₂Cl₂(8 mL) and filtered through celite. After removing the sol-

vent under vacuum, the solid was washed several times with hex-

anes (3 ϫ 2 mL) and then diethyl ether (3 ϫ 2 mL). After drying,

29 was recovered as an orange powder. Suitable crystals for X-ray

structure analysis were grown by diffusion of hexanes into a solu-

tion of CDCl₃.Yield: 89%, 278 mg. ¹H NMR (300 MHz, CDCl₃,

˚

Kα (λ ϭ 0.71070 A) X-ray source and a graphite monochromator.

All data were measured using phi and omega scans. Experimental

details are described in tables 1, 3 and 4. The crystal structures

were solved using SIR 97^[45]and Shelxl-97.^[46]ORTEP drawings

were made using ORTEP III for Windows.^[47]CCDC-210894 to

210900 and 210982 contain the supplementary crystallographic

data for this paper. These data can be obtained free of charge at

www.ccdc.cam.ac.uk/conts/retrieving.html [or from the Cambridge

Crystallographic Data Centre, 12 Union Road, Cambridge

CB2 1EZ, UK; fax: (internat.) ϩ44Ϫ1223/336-033; E-mail:

deposit@ccdc.cam.ac.uk].

2

4

298 K): δ ϭ 1.64 [d, J(P_AϪH) ϭ 13.4, 6 H, CH₃], 5.34 [t, J(H-

P_B) ϭ 4.8, 1 H, H⁴], 6.71Ϫ7.81 (m, 30 H, CH of Ph) ppm. ¹³C

NMR (75.5 MHz, CDCl₃, 298 K): δ ϭ 12.2 [d, ¹J(C-P_A) ϭ 58.4,

CH₃], 67.0 [ddd, ¹J(C-P_A) ϭ 88.8, ¹J(C-P_B) ϭ 76.9, ³J(C-P_BЈ) ϭ

2.9, C^2,6], 118.5 [m, ΣJ(C-P) ϭ 42.8, C⁴H], 127.6Ϫ131.9 (m, CH of

Ph), 136.5 [dd, ¹J(C-P_B) ϭ 85.4, ³J(C-P_A) ϭ 2.5, C of Ph], 142.8

[ddd, ²J(C-P_A) ϭ 10.9, ²J(C-P_B) ϭ 6.9, ⁴J(C-P_BЈ) ϭ 3.3,C^3,5], 157.8

(s, C of Ph) ppm. ³¹P NMR (121.5 MHz, THF, 298 K): δ ϭ 20.77

[AB₂, t, ²J(P_A-P_B) ϭ 41.1, P_A], 37.44 [AB₂, d, ²J(P_A-P_B) ϭ 41.1,

Theoretical Methods: The calculations were performed with the

P_B] ppm. MS (EI): m/z ϭ 712 [M^ϩ]. C₄₃H₃₇P₃S₃(710.81): calcd. C GAUSSIAN 98 series of programs.^[48]The geometries of com-

72.66 H, 5.25; found C 72.28 H, 4.91.

pounds I and II were optimized using the gradient-corrected

Table 5. Crystal data and structural refinement details for 1, 29, 30

1

29

30

Empirical formula

M_r

T [K]

C₄₁H₃₁P₃S₂·CH₂Cl₂

765.61

150.0(1)

monoclinic

P2₁/n

9.4560(10)

28.7580(10)

13.5950(10)

90

95.5600(10)

90

3679.6(5)

4

1.382

0.452

C₄₃H₃₇P₃S₂·CHCl₃

C₄₂H₃₄OP₃S₂·C₁₈H₃₆N₂O₆Na

830.12

1111.20

150.0(1)

triclinic

150.0(1)

monoclinic

P2₁/n

9.225(5)

17.593(5)

24.926(5)

90

92.167(5)

90

4042(3)

4

1.364

0.481

Crystal system

Space group

¯

P1

˚

a [A]

9.127(1)

˚

b [A]

17.624(1)

17.900(1)

94.980(1)

98.650(1)

96.410(1)

2813.0(4)

2

˚

c [A]

α [°]

β [°]

γ [°]

3

˚

V [A ]

Z

ρ [g cm^Ϫ3

]

1.312

0.242

µ [cm^Ϫ1

]

Crystal size [mm]

F(000)

Index ranges

0.22 ϫ 0.09 ϫ 0.09

1584

0.18 ϫ 0.18 ϫ 0.12

1720

Ϫ12 Յ h Յ 12;

21 Յ k Յ 23;

Ϫ31 Յ l Յ 33

phi

28.70/Ͼ2σI

471; 16

17199

10430

7671

0.1098

0.20 ϫ 0.16 ϫ 0.10

1176

Ϫ11 Յ h Յ 11;

35 Յ k Յ 34;

Ϫ16 Յ l Յ 16

phi and omega

26.37/Ͼ2σI

442; 12

13188

7483

5431

0.1168

Ϫ9 Յ h Յ 10;

Ϫ19 Յ k Յ 19;

19 Յ l Յ 19

phi and omega

22.98/Ͼ2σI

677; 8

13666

7760

5963

0.2142

Scan type

2Θ_max[°]/criterion

Param. refined; data/param.

Reflections collected

Independent reflections

Reflections used

wR2

R1

0.0437

1.040

0.0415

1.048

0.0784

1.054

Goodness of fit

Largest diff. peak / hole [e·A

Ϫ3

˚

]

0.352(0.067) / Ϫ0.616(0.067)

0.335(0.064) / Ϫ0.571(0.064)

0.688(0.093) / Ϫ0.475(0.093)

Eur. J. Inorg. Chem. 2003, 3878Ϫ3894

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 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

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´

M. Doux, N. Mezailles, L. Ricard, P. Le Floch

FULL PAPER

Table 6. Crystal data and structural refinement details for 6, 13

6

13

Empirical formula

M_r

T [K]

C₄₁H₃₂ClOP₃PdS₂·CH₂Cl₂

C₅₁H₅₀Cl₃OP₃PdS₂·CH₂Cl₂

1062.72

150.0(1)

orthorhombic

P2₁2₁2₁

9.597(5)

924.47

150.0(1)

monoclinic

P2₁/n

15.644(5)

12.229(5)

21.024(5)

96.100(5)

3999(2)

Crystal system

Space group

˚

a [A]

˚

b [A]

18.767(5)

26.834(5)

˚

c [A]

β [°]

3

˚

V [A ]

4833(3)

Z

4

ρ [g cm^Ϫ3

]

1.535

0.923

1.461

0.774

µ [cm^Ϫ1

]

Crystal size [mm]

F(000)

Index ranges

0.18 ϫ 0.04 ϫ 0.03

1872

0.20 ϫ 0.20 ϫ 0.20

2184

Ϫ13 Յ h Յ 13;

Ϫ26 Յ k Յ 26;

Ϫ37 Յ l Յ 37

phi

30.03/Ͼ2σI

562; 19

13591

Ϫ18 Յ h Յ 18;

Ϫ13 Յ k Յ 14;

Ϫ25 Յ l Յ 25

phi and omega

25.35/Ͼ2σI

470; 10

12483

7319

4986

0.0925

Scan type

2Θ_max[°]/criterion

Param. refined; data/param.

Reflections collected

Independent reflections

Reflections used

wR2

13591

11109

0.1036

R1

0.0482

0.0428

Ϫ0.042(18)

1.022

Flack parameter

Goodness of fit

Largest diff. peak / hole [e·A

1.000

Ϫ3

˚

]

1.212(.104) / Ϫ1.067(.104)

0.486(0.096) / Ϫ0.844(0.096)

Table 7. Crystal data and structural refinement details for 14, 22

14

22

Empirical formula

M_r

T [K]

C₄₅H₄₁ClNP₃PdS₂·CH₂Cl₂

C₄₅H₄₀BrNiP₃S₂·CH₂Cl₂

961.34

150.0(1)

orthorhombic

Pna2₁

19.445(5)

979.59

150.0(1)

monoclinic

P2₁/n

9.507(5)

19.410(5)

24.136(5)

90.290(5)

4454(3)

Crystal system

Space group

˚

a [A]

˚

b [A]

23.835(5)

9.475(5)

˚

c [A]

β [°]

3

˚

V [A ]

4391(3)

Z

4

ρ [g·cm^Ϫ3

]

1.461

0.832

1.454

1.710

µ [cm^Ϫ1

]

Crystal size [mm]

F(000)

Index ranges

0.20 ϫ 0.20 ϫ 0.20

2000

Ϫ13 Յ h Յ 13;

Ϫ27 Յ k Յ 24;

Ϫ33 Յ l Յ 33

phi

30.03/Ͼ2σI

480;18

21883

0.18 ϫ 0.12 ϫ 0.04

1968

Ϫ26 Յ h Յ 26;

Ϫ32 Յ k Յ 32;

Ϫ12 Յ l Յ 12

phi and omega scans

28.70/Ͼ2σI

541;17

11058

9596

0.0945

Scan type

2Θ_max[°]/criterion

Param. refined; data/param.

Reflections collected

Independent reflections

Reflections used

wR2

12955

8989

0.1166

R1

0.0414

0.0399

0.511(7)

1.009

Flack parameter

Goodness of fit

Largest diff. peak / hole [e·A

1.008

Ϫ3

˚

]

0.356(0.090) / 0.874(0.090)

0.200(0.037) / 0.192(0.037)

3892

 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

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Eur. J. Inorg. Chem. 2003, 3878Ϫ3894

Group 10 Metal Complexes of SPS-Based Pincer Ligands

FULL PAPER

density functional theory (DFT) utilizing Becke’s three-parameter

authors thank IDRIS (Paris XI Orsay University) for the allowance

hybrid method B3LYP.^[49,50]The standard 6-311ϩG(d,p) basis set of computer time.

was used for all atoms (C, H, P, O, N, and S). Harmonic

frequencies were calculated at the same level of theory to charac-

[1]

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hydrogen-shift actually connect the two products. Final energies

were optimized, including ZPE energies scaled by the empirical fac-

tor of 0.9806. All optimized structures reported here have only

positive eigenvalues of the Hessian matrix, i.e. they are minima on

the potential energy surface. Optimizations of complexes III, IV,

and V were also carried out with the hybrid B3LYP functional. The

basis set is identical to that used by Frenking and co-workers in

many studies.^[51]The basis set, which is known as ‘‘Basis set II’’,

incorporates the HayϪWadt small-core relativistic effective core

potential^[52]and double-ζ valence basis set (441/2111/31) in con-

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orbitals of the complex are expressed in terms of MOs of appropri-

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the unoccupied MOs of the metal fragment. This value (denoted

d) represents the donation ligand Ǟ [metal fragment]; (ii) the mix-

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of the metal fragment. This value (denoted b) accounts for the back

donation [metal fragment] Ǟ ligand; (iii) the mixing of the occu-

pied MOs of the ligand and the occupied MOs of the metal frag-

ment. This term (denoted r), which describes the repulsive polariz-

ation ligand o [metal fragment], is negative because electronic

charge is removed from the overlapping area of the occupied or-

bitals; (iv) the residual term (∆) which results from the mixing of

the unoccupied MOs of the two respective fragments. Usually this

term is very close to zero for closed-shell interactions. This value

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studied can be really classified as a donorϪacceptor interaction

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Supporting Information Available: ORTEP drawing of compound 5

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Acknowledgments

This work was supported by the CNRS, the Ecole Polytechnique

and the DGA. M. D. thanks the DGA for financial support. The

Eur. J. Inorg. Chem. 2003, 3878Ϫ3894

www.eurjic.org

 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

3893

´

M. Doux, N. Mezailles, L. Ricard, P. Le Floch

FULL PAPER

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Received May 21, 2003

3894

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Eur. J. Inorg. Chem. 2003, 3878Ϫ3894

Article Doi

Group 10 Metal Complexes of SPS-Based Pincer Ligands: Syntheses, X-ray Structures, and DFT Calculations

DOI: 10.1002/ejic.200300303

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