Synthesis and characterization of neutral and cationic platinum(II) complexes featuring pincer-like Bis(phosphino)silyl ligands: Si-H and Si-Cl bond activation chemistry

Article abstract of DOI:10.1021/om9003863

The synthesis and characterization of a new series of Pt(II) complexes bearing the tridentate bis(phosphino)silyl ligands [k³-(2-R ₂PC₆H₄SiMe]^- ([R-PSiP], R = Ph, Cy) are reported. The tertiary silane [Ph-PSiP]H reacted with PtCl ₂(SEt₂)₂ to afford [Ph-PSiP]PtCl (1), which was structurally characterized. Alkyl derivatives of 1 were prepared in high yields by the reaction of 1 with either PhCH₂K to afford [PhPSiP]PtCH ₂Ph (2) or MeLi to afford [Ph-PSiP]PtMe (3). The X-ray crystal structure of 2-CH₂Cl₂ was obtained and confirmed a square-planar geometry about Pt, with the benzyl ligand positioned trans to Si. Treatment of either 2 or 3 with 1 equiv of B(C₆F₅) ₃ in benzene solution led to the formation of the corresponding cationic species {[Ph-PSiP]Pt}⁺[RB(C₆F₅) ₃]^- (R = CH₂Ph, 4; R = Me, 5). X-ray quality crystals of 4(OEt₂) · OEt₂ were grown from an Et₂O solution of 4; the crystal structure of 4(OEt₂) · OEt₂ features an Et₂O molecule coordinated to the cationic Pt center, resulting in square-planar coordination geometry at Pt. Both 4 and 5 underwent a subsequent reaction to generate [Ph-PSiP]Pt(C ₆F₅) (6). Treatment of 1 with 1 equiv of Li[B(C ₆F₅)₄](OEt₂)_2.5 in fluorobenzene afforded {[Ph-PSiP]Pt(OEt₂)}⁺[B(C ₆F₅)₄]^- (7(OEt₂)) · Although the reaction of 1 with AlCl₃ led to a mixture of products, crystallization attempts enabled the isolation of a minute quantity of fluorobenzene-solvated [Ph-PSiP]PtCl-ACl₃ (1(AlCl₃) · (C₆H₅F)₂), which was crystallographically characterized and features a chloride ligand bridging the Pt and Al centers. The dicyclohexylphosphino derivative [Cy-PSiP]H reacted with PtCl₂(SEt₂)₂ in the presence of Et₃N to afford [Cy-PSiP]PtCl (8), which reacted with AgOTf to form [Cy-PSiP]PtOTf (9). Heating of either 8 or 9 for extended periods in benzene solution in the presence of amine bases did not result in benzene activation. Treatment of 8 with RLi reagents (R = Me, Ph) afforded the corresponding methyl ([Cy-PSiP]PtMe, 10) and phenyl ([Cy-PSiP]PtPh, 11) complexes, the latter of which was crystallographically characterized. As was observed for 3, compound 10 reacted with 1 equiv of B(C₆F₅)3 to form {[CyPSiP]Pt} ⁺[MeB(C₆F₅)₃]^- (12), which upon heating in benzene afforded [Cy-PSiP]Pt(C₆F₅) (13) with loss of MeB(C₆F₅)₂. Treatment of 8 with LiEt₃BH led to the formation of [Cy-PSi(μ-H)P]Pt (14), which was identified on the basis of NMR and IR spectroscopic data as a bis(phosphino) Pt derivative of [Cy-PSiP]H that features η²-Si-H coordination involving the tethered silicon fragment. Athough complexes 2,3, and 10 did not react with an atmosphere of H₂, these compounds reacted readily with 1 equiv of PhSiH₃ to form the corresponding silyl complexes ([Ph-PSiP]PtSiH₂Ph, 15; [Cy-PSiP]PtSiH₂Ph, 16) upon loss of toluene or methane, respectively. While 2 and 3 also reacted with 1 equiv of Ph₂SiHCl to form the silyl complex [PhPSiP]PtSiPh₂Cl (17), 10 reacted with either Ph₂SiHCl or ⁱPr₂SiHCl to form [Cy-PSiP]PtCl (8). Complex 10 also reacted with 1 equiv of Me ₃SiCl to form 8 and Me₄Si upon heating. Although complex 11 also reacted with hydridochlorosilanes to form 8, these reactions were significantly slower relative to 10. In contrast to 10 and 11, the η²-Si-H complex 14 reacted with 1 equiv of either PhSiH ₃ or Ph₂SiHCl to form the corresponding Pt silyl complexes 16 and [Cy-PSiP]RSiPh₂Cl (18), with loss of H₂.

Full text of DOI:10.1021/om9003863

5122 Organometallics 2009, 28, 5122–5136
DOI: 10.1021/om9003863
Synthesis and Characterization of Neutral and Cationic Platinum(II)
Complexes Featuring Pincer-like Bis(phosphino)silyl Ligands: Si-H and
Si-Cl Bond Activation Chemistry
Samuel J. Mitton,† Robert McDonald,‡ and Laura Turculet*,†
†Department of Chemistry, Dalhousie University, Halifax, Nova Scotia, Canada B3H 4J3, and ‡X-ray Crystallo-
graphy Laboratory, Department of Chemistry, University of Alberta, Edmonton, Alberta, Canada T6G 2G2
Received May 12, 2009
The synthesis and characterization of a new series of Pt(II) complexes bearing the tridentate bis-
(phosphino)silyl ligands [κ3-(2-R2PC6H4)2SiMe]- ([R-PSiP], R = Ph, Cy) are reported. The tertiary silane
[Ph-PSiP]H reacted with PtCl2(SEt2)2 to afford [Ph-PSiP]PtCl (1), which was structurally characterized.
Alkyl derivatives of 1 were prepared in high yields by the reaction of 1 with either PhCH2K to afford [Ph-
PSiP]PtCH2Ph (2) or MeLi to afford [Ph-PSiP]PtMe (3). The X-ray crystal structure of 2 CH2Cl2 was
3
obtained and confirmed a square-planar geometry about Pt, with the benzyl ligand positioned trans to Si.
Treatment of either 2 or 3 with 1 equiv of B(C6F5)3 in benzene solution led to the formation of the
corresponding cationic species {[Ph-PSiP]Pt}þ[RB(C6F5)3]- (R = CH2Ph, 4; R = Me, 5). X-ray quality
crystals of 4(OEt2) OEt2 were grown from an Et2O solution of 4; the crystal structure of 4(OEt2) OEt2
3
3
features an Et2O molecule coordinated to the cationic Pt center, resulting in square-planar coordination
geometry at Pt. Both 4 and 5 underwent a subsequent reaction to generate [Ph-PSiP]Pt(C6F5) (6).
Treatment of 1 with 1 equiv of Li[B(C6F5)4](OEt2)2.5 in fluorobenzene afforded {[Ph-PSiP]Pt(OEt2)}þ[B-
(C6F5)4]- (7(OEt2)). Although the reaction of 1 with AlCl3 led to a mixture of products, crystallization
attempts enabled the isolation of a minute quantity of fluorobenzene-solvated [Ph-PSiP]PtCl AlCl3
(1(AlCl3) (C6H5F)2), which was crystallographically characterized and features a chloride ligand bridging
3
3
the Pt and Al centers. The dicyclohexylphosphino derivative [Cy-PSiP]H reacted with PtCl2(SEt2)2 in the
presence of Et3N to afford [Cy-PSiP]PtCl (8), which reacted with AgOTf to form [Cy-PSiP]PtOTf (9).
Heating of either 8or 9for extended periods in benzene solution in the presence of amine bases did not result
in benzene activation. Treatment of 8 with RLi reagents (R = Me, Ph) afforded the corresponding methyl
([Cy-PSiP]PtMe, 10) and phenyl ([Cy-PSiP]PtPh, 11) complexes, the latter of which was crystallographi-
cally characterized. As was observed for 3, compound 10 reacted with 1 equiv of B(C6F5)3 to form {[Cy-
PSiP]Pt}þ[MeB(C6F5)3]- (12), which upon heating in benzene afforded [Cy-PSiP]Pt(C6F5) (13) with loss
of MeB(C6F5)2. Treatment of 8 with LiEt3BH led to the formation of [Cy-PSi(μ-H)P]Pt (14), which was
identified on the basis of NMR and IR spectroscopic data as a bis(phosphino) Pt derivative of [Cy-PSiP]H
that features η2-Si-H coordination involving the tethered silicon fragment. Although complexes 2, 3, and 10
did not react with an atmosphere of H2, these compounds reacted readily with 1 equiv of PhSiH3 to form the
corresponding silyl complexes ([Ph-PSiP]PtSiH2Ph, 15; [Cy-PSiP]PtSiH2Ph, 16) upon loss of toluene or
methane, respectively. While 2 and 3 also reacted with 1 equiv of Ph2SiHCl to form the silyl complex [Ph-
PSiP]PtSiPh2Cl (17), 10 reacted with either Ph2SiHCl or iPr2SiHCl to form [Cy-PSiP]PtCl (8). Complex 10
also reacted with 1 equiv of Me3SiCl to form 8 and Me4Si upon heating. Although complex 11 also reacted
with hydridochlorosilanes to form 8, these reactions were significantly slower relative to 10. In contrast to 10
and 11, the η2-Si-H complex 14 reacted with 1 equiv of either PhSiH3 or Ph2SiHCl to form the
corresponding Pt silyl complexes 16 and [Cy-PSiP]PtSiPh2Cl (18), with loss of H2.
Introduction
relatively little attention.4,5 As part of our program targeting
multidentate ancillary ligands that feature formally anionic,
heavier main group element donors, we are interested in the
synthesis and study of pincer-like metal complexes sup-
ported by new tridentate PSiP-type ligands, in anticipation
that such novel bis(phosphino)silyl ligand architectures will
impart unique physical and reactivity properties to the
ensuing complexes.5a,b In particular, the incorporation of
strongly electron donating and trans-labilizing silyl groups6
into such multidentate ligand architectures may promote the
formation of electron-rich and coordinatively unsaturated
complexes that exhibit novel reactivity with σ-bonds.
Phosphine-based “PCP”1,2 and “PNP”1,3 pincer com-
plexes of the platinum group metals have been studied
extensively in recent years, due in part to their involvement
in challenging σ-bond activation reactions (e.g., C-H, C-C,
C-N). Despite recent advances in these areas, alternative
PXP (X=anionic donor) pincer frameworks have received
*To whom correspondence should be addressed. Fax: 1-902-494-
1310. Tel: 1-902-494-6414. E-mail: laura.turculet@dal.ca.
(1) The Chemistry of Pincer Compounds; Morales-Morales, D., Jensen,
C. M., Eds.; Elsevier: Oxford, 2007.
r
pubs.acs.org/Organometallics
Published on Web 08/13/2009
2009 American Chemical Society

Article
In this contribution, we detail the synthesis and reactivity
Organometallics, Vol. 28, No. 17, 2009 5123
Scheme 1. Synthesis of [Ph-PSiP]PtX Complexesa
studies of new neutral and cationic platinum(II) complexes
supported by bis(phosphino)silyl ligands of the type [κ3-(2-
R2PC6H4)2SiMe]- ([R-PSiP], R = Ph, Cy).7 Organoplati-
num complexes have been shown to mediate numerous
chemical transformations involving E-H (E = main group
element) bond activation, including most notably Si-H
bond activation processes such as hydrosilylation,8 as well
as C-H bond activation and functionalization.9 Studies
documenting the influence of multidentate ligation on Pt-
mediated E-H bond activation chemistry have contributed
significantly to the development of increasingly reactive
organoplatinum species. In this context, recent reports by
the groups of Peters (NNN pincers)10 and Liang (PNP
pincers)11 serve to highlight the utility of tridentate pincer-
type ligation in supporting reactive Pt complexes for inter-
molecular C-H bond activation. Having demonstrated that
[Cy-PSiP]Ir complexes can mediate arene C-H bond activa-
tion under mild conditions,5a we became interested in estab-
lishing the synthetic feasibility of [R-PSiP] ligation in square-
planar Pt(II) complexes and in examining the reactivity of
such complexes in σ-bond activation.
a Reagents: (i) PtCl2(SEt2)2; (ii) KCH2Ph (R=CH2Ph), MeLi (R=
Me).
synthesis of alkyl and hydrido complexes of Pt(IV) sup-
ported by the NSiN-type bis(8-quinolyl)methylsilyl ligand.12
Although these workers also reported the synthesis of a
Pt(II) chloride complex supported by such NSiN ligation,
subsequent attempts to prepare Pt(II) alkyl or hydrido
derivatives were unsuccessful, and NSiN ligation appears
to favor the formation of stable Pt(IV) species. These reports
notwithstanding, the synthesis of silyl pincer Pt(II) organo-
metallic species and the study of such complexes with respect
to E-H bond activation had not been documented prior to
our work. By comparison with the Stobart systems, we
anticipated that the reduced conformational flexibility and
lack of β-hydrogens associated with the ortho-phenylene
backbone of [R-PSiP] could provide enhanced stability
and selectivity in Pt-mediated substrate transformations.
Furthermore, in comparison with the quinolyl-based NSiN
system studied by Tilley and co-workers, we viewed [R-PSiP]
ligation as offering the opportunity to readily tune the steric
and electronic properties of the phosphino donors; the
phosphino groups were also anticipated to be compatible
with the preparation of electron-rich Pt(II) derivatives.
Although C-H bond activation was not observed for the
new [R-PSiP]Pt (R=Ph, Cy) species featured herein, exam-
ples of both Si-H and net Si-Cl bond activation mediated
by these complexes are reported.13
Precedent for related tridentate silyl ligands in Pt coordi-
nation chemistry has been established by the groups of
Stobart and Tilley. Stobart and co-workers have reported
the synthesis of several Pt(II) chloride complexes supported
by bis(phosphino)silyl ligands that feature either aliphatic or
benzylic ligand backbones;5c,d notably, the organometallic
reactivity of these complexes has not been explored to date.
More recently, Tilley and co-workers have reported on the
(2) For selected reviews and recent examples, see: (a) Jensen, C. M.
Chem. Commun. 1999, 2443. (b) van der Boom, M. E.; Milstein, D. Chem.
Rev. 2003, 103, 1759. (c) Goettker-Schnetmann, I.; White, P.; Brookhart, M.
J. Am. Chem. Soc. 2004, 126, 1804. (d) Zhao, J.; Goldman, A. S.; Hartwig,
J. F. Science 2005, 307, 1080. (e) Goldman, A. S.; Roy, A. H.; Huang, Z.;
Ahuja, R.; Schinski, W.; Brookhart, M. Science 2006, 312, 257. (f) Albrecht,
M.; van Koten, G. Angew. Chem., Int. Ed. 2001, 40, 3750.
(3) For selected reviews and recent examples, see: (a) Liang, L.-C.
Coord. Chem. Rev. 2006, 250, 1152. (b) Walstrom, A.; Pink, M.; Tsvetkov,
N. P.; Fan, H.; Ingleson, M.; Caulton, K. G. J. Am. Chem. Soc. 2005, 127,
16780. (c) Watson, L. A.; Ozerov, O. V.; Pink, M.; Caulton, K. G. J. Am.
Chem. Soc. 2003, 125, 8426. (d) Gatard, S.; Celenligil-Cetin, R.; Guo, C.;
Foxman, B. M.; Ozerov, O. V. J. Am. Chem. Soc. 2006, 128, 2808. (e) Fan,
L.; Parkin, S.; Ozerov, O. V. J. Am. Chem. Soc. 2005, 127, 16772. (f) Ozerov,
O. V.; Guo, C.; Papkov, V. A.; Foxman, B. M. J. Am. Chem. Soc. 2004, 126,
4792. (g) Fryzuk, M. D. Can. J. Chem. 1992, 70, 2839.
(4) For X = B or P, see: (a) Mazzeo, M.; Lamberti, M.; Massa, A.;
Scettri, A.; Pellecchia, C.; Peters, J. C. Organometallics 2008, 27, 5741.
(b) Segawa, Y.; Yamashita, M.; Nozaki, K. J. Am. Chem. Soc. 2009, 131,
9201.
(5) For X = Si, see: (a) MacLean, D. F.; McDonald, R.; Ferguson,
M. J.; Caddell, A. J.; Turculet, L. Chem. Commun. 2008, 5146.
(b) MacInnis, M. C.; MacLean, D. F.; Lundgren, R. J.; McDonald, R.;
Turculet, L. Organometallics 2007, 26, 6522. (c) Gossage, R. A.; McLennan,
G. D.; Stobart, S. R. Inorg. Chem. 1996, 35, 1729. (d) Brost, R. D.; Bruce, G.
C.; Joslin, F. L.; Stobart, S. R. Organometallics 1997, 16, 5669. (e) Bushnell,
G. W.; Casado, M. A.; Stobart, S. R. Organometallics 2001, 20, 601. (f)
Zhou, X.; Stobart, S. R. Organometallics 2001, 20, 1898. (g) Takaya, J.;
Iwasawa, N. J. Am. Chem. Soc. 2008, 130, 15254.
Results and Discussion
Synthesis of [Ph-PSiP]Pt(II) Complexes. Treatment of
[Ph-PSiP]H with 1 equiv of PtCl2(SEt2)2 in benzene solution
led to the precipitation of microcrystalline [Ph-PSiP]PtCl (1,
Scheme 1), which was isolated in 95% yield. Although
isolated 1 exhibited poor solubility in a wide range of
solvents (including benzene, THF, and dichloromethane),
solution NMR spectroscopic data for 1 (chloroform-d) are
consistent with a Cs symmetric structure, as indicated by the
presence of one 31P{1H} NMR resonance at 51.7 ppm (s with
Pt satellites, JPPt = 3074 Hz). The observation of 195Pt
1
satellites in both the 31P and 29Si (35.6 ppm; JSiPt =1110
1
Hz) NMR spectra of 1 is consistent with κ3-coordination of
the [Ph-PSiP] ligand. Slow evaporation of a benzene solu-
tion of 1 provided a crystal suitable for single-crystal X-ray
diffraction analysis. The solid state structure of 1 (Figure 1,
Table 1) features distorted square-planar geometry at Pt and
is consistent with the solution NMR data obtained for this
complex, thereby unequivocally confirming that [Ph-PSiP]
ligation can accommodate the formation of square-planar
(6) (a) Tilley, T. D. In The Silicon-Heteroatom Bond; Patai, S.,
Rappoport, Z., Eds.; Wiley: New York, 1991. (b) Corey, J. Y.; Braddock-
Wilking, J. Chem. Rev. 1999, 99, 175.
(7) A portion of this work has been communicated; see ref 5b.
(8) (a) Ojima, I. In The Chemistry of Organic Silicon Compounds;
Patai, S., Rappoport, Z., Eds.; Wiley: Chichester, UK, 1989. (b) Brook, M. A.
Silicon in Organic, Organometallic, and Polymer Chemistry; Wiley: New
York, 2000.
(9) For selected recent reviews see: (a) Labinger, J. A.; Bercaw, J. E.
Nature 2002, 417, 507. (b) Fekl, U.; Goldberg, K. I. Adv. Inorg. Chem.
2003, 54, 259. (c) Lersch, M.; Tilset, M. Chem. Rev. 2005, 105, 2471.
(10) Harkins, S. B.; Peters, J. C. Organometallics 2002, 21, 1753.
(11) Liang, L.-C.; Lin, J.-M.; Lee, W.-Y. Chem. Commun. 2005, 2462.
(12) Sangtrirutnugul, P.; Tilley, T. D. Organometallics 2008, 27, 2223.
(13) During the course of these studies, related [κ3-(2-iPr2PC6-
H4)2SiR]Pt complexes (R = OH or H) were reported by Milstein and
co-workers: Korshin, E. E.; Leitus, G.; Shimon, L. J. W.; Konstantinovski,
L.; Milstein, D. Inorg. Chem. 2008, 47, 7177.

5124 Organometallics, Vol. 28, No. 17, 2009
Mitton et al.
corresponds to the benzylic (2.76 ppm, 2JHPt=69 Hz, 3JHP
6 Hz) and methyl (1.01 ppm, JHPt =52 Hz, JHP =5 Hz)
protons, respectively, of the Pt alkyl ligand.
=
2
3
X-ray quality crystals were obtained from a concentrated
dichloromethane solution of 2 at -30 °C. The solid state
structure of 2 CH2Cl2 (Figure 2, Table 1) features distorted
3
square-planar geometry at Pt and is consistent with the
solution NMR data obtained for this complex, thereby
confirming that [Ph-PSiP] ligation can accommodate the
formation of square-planar complexes that feature a
strongly trans-labilizing alkyl ligand coordinated trans to
Si. As in the case of 1, the P1-Pt-P2 angle of 162.98(7)° is
less than the ideal 180° value expected for a square-planar
˚
structure. The Pt-Si distance of 2.356(2) A is longer than the
˚
Pt-Si distance observed for 1 (2.278(2) A), which is in
keeping with the stronger trans-influence of the benzyl ligand
˚
relative to chloride. The Pt-C2 bond distance of 2.201(6) A
is comparable to that previously reported for the PCP and
PNP pincer complexes C6H3[CH2P(tBu)2][CH2CH2N-
(Me)2]PtCH3 (Pt-CMe=2.187(5) A)14 and [(2-Ph2PC6H4)2-
Figure 1. ORTEP diagram for 1 shown with 50% displacement
ellipsoids; all H-atoms have been omitted for clarity. Selected
interatomic distances (A) and angles (deg) for 1: Pt-Cl 2.437(2);
˚
11
˚
˚
N]PtCH3 (Pt-CMe=2.11(3) A).
Attempts to prepare [Ph-PSiP]PtH by the reaction of 1
with 1 equiv of LiEt3BH (1.0 M in THF) led to the formation
of multiple phosphorus-containing products, as indicated by
31P NMR spectroscopy of the reaction mixture. No tractable
[Ph-PSiP]Pt species could be isolated from this mixture. We
also attempted to prepare a hydride complex by hydrogeno-
lysis (1 atm H2) of either 2 or 3 in benzene solution; however,
no reaction was observed between 2 or 3 and H2 even after
prolonged (5 days) heating at 80 °C.
Pt-P1 2.261(2); Pt-P2 2.261(2); Pt-Si 2.278(2); Cl-Pt-Si
169.32(6); P1-Pt-P2 155.36(6).
complexes. The P1-Pt-P2 angle of 155.36(6)° is less than
the ideal 180° value expected for a square-planar structure,
most likely due to the constraints imposed by the rigid [Ph-
PSiP] ligand backbone and sp3-hybridization at Si. The
˚
Pt-Si distance of 2.278(2) A falls within the range character-
6b
˚
istic of Pt-Si bond distances (2.255-2.444 A), and the
˚
Pt-Cl bond distance of 2.437(2) A is comparable to that
Both complexes 2 and 3 exhibited high thermal stability in
benzene solution; no reaction was observed upon heating
benzene solutions of either 2 or 3 at 90-100 °C over the
course of several days. In an effort to access a cationic [Ph-
PSiP]Pt complex that may exhibit reactivity with the C-H
bonds of benzene, 2 was treated with 1 equiv of B(C6F5)3.
This reaction in benzene solution led to the clean precipita-
tion of a microcrystalline product (4, 89% yield) that is
derived from benzyl anion abstraction in 2 (eq 1), as indi-
observed for the related complexes [κ3-(Ph2PCH2CH2-
CH2)2SiMe]PtCl (Pt-Cl=2.436(6) A)5d and [κ3-(2-iPr2PC6-
˚
13
˚
H4)2SiOH]PtCl (Pt-Cl=2.4694(9) A).
Complex 1 was utilized as the precursor for the synthesis of
alkyl platinum complexes that we considered would be good
candidates for the study of E-H bond activation chemistry.
Treatment of sparingly soluble 1 with 1 equiv of either
KCH2Ph or MeLi (1.6 M in Et2O) in THF led to formation
of the corresponding alkyl complexes, [Ph-PSiP]PtCH2Ph
(2) and [Ph-PSiP]PtMe (3, Scheme 1), respectively, which
were each isolated as yellow solids in near quantitative yield.
Complexes 2 and 3 represent the first examples of Pt(II) alkyl
complexes supported by silyl pincer ligation.
1
cated by H and 11B{1H} NMR spectroscopy of the redis-
solved solid in bromobenzene-d5. While the 1H NMR
resonance for the benzylic protons of complex 2 is observed
as a triplet with 195Pt satellites at 2.76 ppm (2JHPt=69 Hz,
3JHP = 6 Hz, benzene-d6), the resonance corresponding to
the benzylic protons of 4 is observed as a singlet at 3.44 ppm
(bromobenzene-d5). The formation of the [B(C6F5)3(CH2-
Ph)]- anion was supported by the 11B{1H} NMR spectrum
of 4 (bromobenzene-d5), which features a single resonance at
-17.4 ppm. In addition, the 31P (48.1 ppm, 1JPPt=3016 Hz,
The 29Si, 31P, and 1H NMR spectra of 2 and 3 (benzene-d6)
are consistent with the formation of square-planar species
that feature tridentate coordination of the [Ph-PSiP] ligand
with the alkyl ligand occupying the coordination site trans to
Si. The 29Si NMR spectra of 2 and 3 each feature a resonance
with Pt satellites at 51.0 (1JSiPt=565 Hz) and 60.5 (1JSiPt
=
1
bromobenzene-d5) and 29Si (26.6 ppm, JSiPt = 976 Hz,
647 Hz) ppm, respectively, in keeping with the coordination
of Si to the Pt center for both complexes. The decreased
bromobenzene-d5) NMR resonances of 4 are shifted sub-
stantially upfield relative to 2 (Table 2). The increased value
1
values of JSiPt for both 2 and 3 relative to 1 are consistent
1
of JSiPt for 4 relative to 2 is also in keeping with benzyl
with weakening of the Pt-Si bond due to the greater trans-
influence of the benzyl and methyl ligands versus chloride.
Indeed, a general trend of increasing δ 29Si and decreasing
1JSiPt with increasing trans-influence of the ligand (X) posi-
tioned trans to Si in the series of [R-PSiP]PtX complexes
featured herein is evident (Table 2). The 31P{1H} NMR
spectra of 2 and 3 each contain a single resonance with Pt
satellites at 54.6 (s, 1JPPt=3092 Hz) and 57.4 (s, 1JPPt= 3012
Hz) ppm, respectively, consistent with the formation of a Cs-
symmetric complex in each case. Lastly, the 1H NMR spectra
of 2 and 3 each feature a triplet with Pt satellites that
abstraction (Table 2). In light of observations by Kubas and
co-workers15 that Pt cations of the type [trans-(R3P)2PtH]þ
coordinate a range of solvents, including Et2O, CH2Cl2, and
bromobenzene, 4 and the related cations featured herein
(vide infra) may coordinate solvent when dissolved in polar
media such as bromobenzene. A related example of a
(14) Poverenov, E.; Gandelman, M.; Shimon, L. J. W.; Rozenberg,
H.; Ben-David, Y.; Milstein, D. Chem.;Eur. J. 2004, 10, 4673.
(15) Butts, M. D.; Scott, B. L.; Kubas, G. J. J. Am. Chem. Soc. 1996,
118, 11831.

Article
Organometallics, Vol. 28, No. 17, 2009 5125
Table 1. Crystallographic Data for 1, 1(AlCl3) (C6H5F)2, 2 CH2Cl2, 4(OEt2) OEt2, and 11 OEt2
3
1(AlCl3) (C6H5F)2
3
3
2 CH2Cl2
3
4(OEt2) OEt2
1
11 OEt2
3
3
3
3
empirical formula
fw
C37H31ClP2PtSi
796.19
C49H41AlCl4F2P2PtSi
1121.72
C45H40Cl2P2PtSi
936.79
C70H58BF15O2P2PtSi
1512.09
C47H70OP2PtSi
936.15
cryst dimens
cryst syst
space group
0.17 ꢀ 0.12 ꢀ 0.09
monoclinic
P21/c
9.9109(10)
13.6560(15)
23.845(3)
90
97.9035(15)
90
3196.7(6)
4
1.654
0.42 ꢀ 0.34 ꢀ 0.28
orthorhombic
P212121
16.1110(14)
16.9890(15)
17.4373(15)
90
90
90
4772.8(7)
4
1.561
0.38 ꢀ 0.14 ꢀ 0.11
0.46 ꢀ 0.19 ꢀ 0.08
0.45 ꢀ 0.39 ꢀ 0.15
triclinic
P1
triclinic
P1
triclinic
P1
˚
a (A)
13.5856(14)
16.9084(17)
19.771(2)
89.7276(14)
76.0291(14)
67.8835(13)
4064.2(7)
4
1.531
3.723
0.6849-0.3320
55.06
14.7176(12)
14.9566(13)
15.4025(13)
100.4012(10)
103.4242(10)
99.6020(10)
3165.5(5)
2
1.586
2.377
0.8253-0.4110
55.18
13.506(5)
14.057(5)
14.950(6)
116.378(4)
93.480(4)
112.518(4)
2255.8(15)
2
1.378
3.240
0.6387-0.3209
55.06
˚
b (A)
˚
c (A)
R (deg)
β (deg)
γ (deg)
3
˚
V (A )
Z
F
calcd (g cm-3
)
μ (mm-1
range of transmn
)
4.636
0.6831-0.5115
52.82
3.316
0.4570-0.3365
54.98
2θ limit (deg)
-12 e h e 12
-17 e k e 17
-29 e l e 29
24 954
6528
0.0727
4728
-20 e h e 20
-21 e k e 21
-22 e l e 22
41 683
10 903
0.0278
10 102
-17 e h e 17
-21 e k e 21
-25 e l e 25
35 744
18 477
0.0439
12 519
-19 e h e 19
-19 e k e 19
-20 e l e 20
27 707
14 387
0.0352
11 723
-17 e h e 17
-17 e k e 17
-19 e l e 19
19 714
10 198
0.0133
9813
total data collected
indep reflns
Rint
obsd reflns
data/restraints/params
goodness-of-fit
R1 [F2o g 2σ(F2o)]
wR2 [F2o g -3σ(F2o)]
6528/0/379
1.082
0.0344
0.1010
1.535, -0.862
10 903/0/501
1.023
0.0254
0.0625
1.338, -0.627
18 477/2/885
1.042
0.0498
0.1423
2.542, -1.876
14 387/0/820
1.018
0.0308
0.0676
1.059, -0.995
10 198/0/469
1.030
0.0157
0.0412
0.836, -0.471
-3
˚
largest peak, hole (e A
)
Table 2. Comparison of 29Si NMR Data for Square-Planar
[R-PSiP]PtX Complexesa
compound
ligand trans to Si (X)
29Si NMR δ
1JSiPt
9b
OTf
18.8
22.9
26.6d
30.4
32.2d
32.3
35.6
51.0
51.6
53.8
59.7
60.5
63.9
71.6e
74.9e
81.6e
1381
971
12b
4c
976d
1178
1216d
1183
1110
565
5c
c
7(OEt2)0.5
8b
Cl
Cl
CH2Ph
C6F5
C6F5
Ph
Me
Me
SiPh2Cl
SiPh2Cl
SiH2Ph
1c
2c
6c
813
806
646
647
13b
11b
3c
10b
17c
18b
16b
696
556e
638e
650e
Figure 2. ORTEP diagram for 2 CH2Cl2 shown with 50%
3
a In benzene-d6. b R = Cy. c R = Ph. d In bromobenzene-d5. e For [R-
PSiP] fragment.
displacement ellipsoids; all H-atoms, as well as the dichloro-
methane solvate, have been omitted for clarity. Only one of the
two crystallographically independent molecules of 2 CH2Cl2 is
3
[{κ3-(2-iPr2PC6H4)2Si(OH)}Pt]þ[(C6F5)4B]- species was re-
˚
shown. Selected interatomic distances (A) and angles (deg) for
2 CH2Cl2: Pt1A-P1A 2.261(2); Pt1A-P2A 2.260(2); Pt-
cently reported by Milstein and co-workers.13
3
1A-Si1A 2.356(2); Pt1A-C2A 2.201(6); P1A-Pt1A-P2A
162.98(7); Si1A-Pt1A-C2A 175.7(2).
in distorted square-planar coordination geometry at Pt.
Although Et2O is a relatively weak donor ligand, related
examples of cationic trans-bis(phosphino) platinum hy-
dride species that coordinate weak donors such as THF,
H2, and halocarbons have been reported;15,16 neutral and
cationic late metal pincer complexes featuring weakly co-
ordinating ligands trans to the central anionic donor are also
A crystal suitable for single-crystal X-ray diffraction
studies was grown from a concentrated diethyl ether solution
known.1,2b,2f,3a The Pt-O1 distance of 2.282(2) A is slightly
˚
of 4 at -30 °C. The solid state structure of 4(OEt2) OEt2
3
(Figure 3, Table 1) features an equivalent of Et2O coordi-
nated to the cationic Pt center (as well as a noncoordinated
equivalent of Et2O within the crystal lattice), resulting
(16) Gusev, D. G.; Notheis, J. U.; Rambo, J. R.; Hauger, B. E.;
Eisenstein, O.; Caulton, K. G. J. Am. Chem. Soc. 1994, 116, 7409.

5126 Organometallics, Vol. 28, No. 17, 2009
Mitton et al.
mmHg). Spectroscopic characterization of 6 led to the
assignment of this compound as the product of a redistribu-
tion reaction involving C6F-5 transfer from B to Pt to form
[Ph-PSiP]Pt(C6F5). As expected, isolated 6 does not exhibit a
11B NMR resonance. However, the 19F{1H} NMR spectrum
of 6 (25 °C, benzene-d6) features a set of broad resonances at
-113.2 (m, 1 F, C6F5ortho), -115.4 (m, 1 F, C6F5ortho), and
-162.9 to -164.2 (overlapping resonances, 3 F, C6F5para and
C6F5meta) ppm that are consistent with the fluorine substit-
uents of the Pt-C6F5 group in which rotation about the
Pt-C bond by 180° is slow on the NMR time scale at 25 °C.
In keeping with this scenario, temperature-dependent 19F-
{1H} NMR features were observed for 6 in the range 25-
80 °C, with coalescence of the two resonances corresponding
to the ortho-F substituents observed at 70 °C (benzene-d6,
470.8 MHz, ΔGq=15 kcal mol-1). Heating a fluorobenzene
solution of 4 at 100 °C for 36 h also led to the quantitative
formation of 6, as indicated by 1H, 31P, and 19F NMR
spectroscopy. While aryl transfer from [RB(C6F5)3]- (R=
alkyl) to cationic early transition metal centers is well
established,18,19 examples of similar reactivity involving late
transition metal cations are not as common.20 Related
examples of aryl transfer from [BPh4]-,21 as well as [B(3,5-
(CF3)2C6H3)4]-,22 to cationic late metal centers have also
been documented.
Figure 3. ORTEP diagram for 4(OEt2) OEt2 shown with 50%
3
displacement ellipsoids; all H-atoms, as well as the borate anion
and the diethyl ether solvate, have been omitted for clarity.
˚
Selected interatomic distances (A) and angles (deg) for 4-
(OEt2) OEt2: Pt-P1 2.2935(8); Pt-P2 2.3050(8); Pt-Si
3
2.2762(8); Pt-O1 2.282(2); P1-Pt-P2 165.55(3); Si-Pt-O1
178.41(7).
˚
elongated relative to the Pt-O distance of 2.224(7) A found
for [trans-(iPr3P)2PtH(THF)]þ.15 The Pt-Si distance of
˚
2.2762(8) A in 4(OEt2) OEt2 is significantly shorter than
3
that noted for 2 CH2Cl2, but is comparable to the Pt-Si
3
distance observed in the solid state structure of 1.
No reaction was observed upon heating a suspension of 4
in benzene solution to 90 °C over the course of several days.
In an effort to access an analogue of 4 that might prove more
soluble in benzene, the methyl derivative 3 was also reacted
with 1 equiv of B(C6F5)3. The reaction of 3 with B(C6F5)3 in
benzene solution is complete within a few minutes at room
temperature to afford quantitatively (1H and 31P NMR)
a product (5) that is consistent with methide abstraction
to form {[Ph-PSiP]Pt}þ[B(C6F5)3Me]-. Unlike the related
complex 4, compound 5 appears to be relatively soluble in
benzene, as no precipitation was observed from the reaction
mixture. Complex 5 features a characteristic, sharp 11B{1H}
NMR resonance at -14.0 ppm (benzene-d6). The B-Me
protons are observed as a singlet at 1.43 ppm in the
1H NMR spectrum of 5 (benzene-d6), as contrasted with
the Pt-Me protons in 3, which are observed as a triplet with
Alternative approaches for accessing cationic [Ph-PSiP]Pt
species from the Pt chloride complex 1 were also attempted.
Treatment of 1 with 1 equiv of Li[B(C6F5)4](OEt2)2.5 in
fluorobenzene solution led to the quantitative (31P NMR)
formation of {[Ph-PSiP]Pt(OEt2)}þ[B(C6F5)4]- (7(OEt2),
eq 3); our tentative formulation of 7(OEt2) as featuring a
coordinated Et2O molecule is based on the crystallographic
3
2
Pt satellites at 1.01 ppm (benzene-d6, JHP =5 Hz, JHPt
52 Hz).
=
Although complex 5 was generated quantitatively in ben-
zene solution, upon standing in benzene solution at room
temperature, 5 undergoes a reaction to generate a new [Ph-
PSiP]Pt-containing product (6, eq 2). At room temperature,
the conversion of 5 to 6 is ca. 90% complete after 20 h, as
indicated by 1H and 31P NMR spectroscopy; heating a
benzene solution of 5 at 65 °C leads to complete conversion
to 6 after 2 h. Analysis of the reaction mixture by 11B{1H}
NMR spectroscopy indicated a new broad resonance at 71.3
ppm (benzene-d6) that is consistent with the formation of
MeB(C6F5)2.17 The 1H NMR spectrum of the reaction
mixture (benzene-d6) features a resonance at 1.33 ppm that
exhibits fine structure consistent with a quintet (J = 2 Hz);
this resonance is assigned to the B-Me protons of MeB-
(C6F5)2, which experience coupling to the four ortho-fluorine
substituents of the two perfluorinated aromatic groups.17,18
Compound 6 was readily isolated (94% yield) by removing
the volatile MeB(C6F5)2 side product under vacuum (0.001
characterization of 4(OEt2) OEt2. Upon scale-up, 7-
3
(OEt2)0.5 was isolated as a pale yellow solid in 92% yield;
efforts to completely remove the diethyl ether solvate from
this isolated material in vacuo have thus far been unsuccess-
ful. While NMR spectroscopic characterization data for the
isolated material in bromobenzene-d5 solution are consistent
with the presence of half an equivalent of free Et2O that is not
coordinated to the Pt center, the displacement of coordi-
nated Et2O from the metal coordination sphere by bromo-
(19) For selected examples see: (a) Thorn, M. G.; Etheridge, Z. C.;
Fanwick, P. E.; Rothwell, I. P. Organometallics 1998, 17, 3636.
ꢀ
(b) Guerin, F.; Stewart, J. C.; Beddie, C.; Stephan, D. W. Organometallics
2000, 19, 2994. (c) Scollard, J. D.; McConville, D. M.; Rettig, S. J.
Organometallics 1997, 16, 1810. (d) Woodman, T. J.; Bochman, M.;
Thornton-Pett, M. Chem. Commun. 2001, 329. (e) Metcalfe, R. A.; Kreller,
D. I.; Tian, J.; Kim, H.; Taylor, N. J.; Corrigan, J. F.; Collins, S. Organome-
tallics 2002, 21, 1719.
(20) Barlow, G. K.; Boyle, J. D.; Cooley, N. A.; Ghaffar, T.; Wass,
D. F. Organometallics 2000, 19, 1470.
(21) (a) Aresta, M.; Quaranta, E.; Tommasi, I. New J. Chem. 1997, 21,
595, and references therein. (b) Ashworth, T. V.; Nolte, M. J.; Reimann, R. H.;
Singleton, E. J. Chem. Soc., Chem. Commun. 1977, 937.
(22) (a) Salem, H.; Shimon, L. J. W.; Leitus, G.; Weiner, L.; Milstein,
D. Organometallics 2008, 27, 2293. (b) Konze, W. V.; Scott, B. L.; Kubas,
G. J. Chem. Commun. 1999, 1807.
(17) Qian, B.; Ward, D. L.; Smith, M. R.III Organometallics 1998, 17,
3070.
(18) Yang, X.; Stern, C. L.; Marks, T. J. J. Am. Chem. Soc. 1994, 116,
10015.

Article
Organometallics, Vol. 28, No. 17, 2009 5127
Scheme 2. Synthesis of [Cy-PSiP]PtX Complexesa
Figure 4. ORTEP diagram for 1(AlCl3) (C6H5F)2 shown with
3
50% displacement ellipsoids; all H-atoms, as well as the fluoro-
benzene solvate, have been omitted for clarity. Selected inter-
a Reagents: (i) PtCl2(SEt2)2, Et3N; (ii) AgOTf; (iii) RLi (R = Me, Ph);
(iv) B(C6F5)3.
˚
atomic distances (A) and angles (deg) for 1(AlCl3) (C6H5F)2:
3
Pt-Cl1 2.5640(9); Pt-P1 2.2889(8); Pt-P2 2.2888(8); Pt-Si
2.2851(9); Cl1-Pt-Si 178.20(3); P1-Pt-P2 164.17(3).
benzene led to formation of the Si-H bond activation
product [Cy-PSiP]PtCl (8, Scheme 2) and Et3N HCl upon
benzene-d5 cannot be ruled out. Complex 7(OEt2)0.5 features
a characteristic sharp 11B NMR resonance at -15.9 ppm
(bromobenzene-d5), as well a 1JSiPt value that is higher than
that observed for 1 (Table 2), which is consistent with
chloride abstraction. Complex 7(OEt2)0.5 does not react
further in benzene solution upon heating at 100 °C for 3 days.
3
heating at 65 °C for 30 h. Complex 8 was isolated as an off-
white analytically pure solid in 86% yield. The related
complex [Cy-PSiP]PtOTf (9, Scheme 2) was obtained in
87% yield by treating 8 with 1 equiv of AgOTf in benzene
solution. The NMR spectra of 8 and 9 (benzene-d6) are
consistent with tridentate coordination of the [Cy-PSiP]
ligand to form Cs-symmetric complexes.
Neither 8 nor 9 reacted upon heating in benzene solution
at 100 °C for extended periods of time in the presence of
amine bases such as Et3N and iPr2MeN. As such, we under-
took the synthesis of alkyl platinum derivatives that could
potentially exhibit increased reactivity. Treatment of 8 with
1 equiv of MeLi (1.6 M in Et2O) in THF led to formation of
the methyl complex [Cy-PSiP]PtMe (10, Scheme 2), which
was isolated as a pale yellow solid in 55% yield. Similarly,
treatment of 8 with 1 equiv of PhLi (1.8 M in nBu2O) in THF
led to formation of the corresponding phenyl complex [Cy-
PSiP]PtPh (11, Scheme 2), which was isolated as a yellow
solid in 94% yield.
In an effort to further explore the reactivity of 1, 1 equiv of
AlCl3 was added to a fluorobenzene solution of this com-
pound. While 31P NMR analysis of this intractable reaction
mixture confirmed the formation of multiple phosphorus-
containing products, crystallization attempts enabled the
isolation of a minute quantity of crystalline material (from
a fluorobenzene solution) that proved suitable for single-
crystal X-ray diffraction analysis. The crystallographically
characterized material (Figure 4, Table 1) corresponds to
Solution NMR data for 10 and 11 (benzene-d6) are con-
sistent with the formation of Cs-symmetric square-planar
complexes that feature tridentate coordination of the [Cy-
PSiP] ligand with the Pt-Me and Pt-Ph ligands, respectively,
occupying the coordination site trans to Si. The 29Si NMR
spectra of 10 and 11 each feature a resonance with Pt
satellites at 63.9 (1JSiPt = 696 Hz) and 59.7 (1JSiPt = 646
Hz) ppm, respectively, consistent with the coordination of Si
fluorobenzene-solvated [Ph-PSiP]PtCl AlCl3 (1(AlCl3)), in
3
which a chloride ligand bridges Pt and Al centers. The solid
state structure of 1(AlCl3) (C6H5F)2 features a Pt-Si dis-
3
˚
tance of 2.2851(9) A, which is similar to that observed in the
1
˚
solid state structures of 1 (2.278(2) A) and 4(OEt2) (OEt2)
to the Pt center for both complexes. While the H NMR
3
˚
resonance corresponding to the Pt-Me group in 10 is ob-
scured by resonances for the cyclohexyl protons of the [Cy-
PSiP] ligand, the 13C{1H} NMR spectrum of 10 contains a
resonance at -1.6 ppm (t, J = 8 Hz) that is assigned to the
Pt-Me group and which correlates to a 1H NMR resonance
at 1.25 ppm in a 1H-13C HSQC experiment.
(2.2762(8) A). As expected, the Pt-Cl bond distance in
1(AlCl3) (C6H5F)2 is significantly longer than that observed
˚
for 1 (2.5640(9) vs 2.437(2) A), which is in keeping with
3
partial chloride abstraction from Pt by the Lewis acidic Al
center.
Synthesis of [Cy-PSiP]Pt(II) Complexes. In order to com-
plement our investigations of [Ph-PSiP]Pt(II) chemistry, we
sought to examine the Pt coordination chemistry of the
related dicyclohexylphosphino-substituted ligand [Cy-PSiP]
and the reactivity of the resulting complexes. In particular,
we anticipated that the differing steric and electronic proper-
ties of [Cy-PSiP] relative to [Ph-PSiP] might lead to divergent
reactivity for the associated Pt(II) complexes. Treatment of
[Cy-PSiP]H with 1 equiv each of PtCl2(SEt2)2 and Et3N in
X-ray quality crystals were obtained from a concentrated
diethyl ether solution of 11. The solid state structure of
11 OEt2 (Figure 5, Table 1) features distorted square-planar
3
geometry at Pt and is consistent with the solution NMR data
obtained for this complex, confirming that, as in the case
of [Ph-PSiP], [Cy-PSiP] ligation can accommodate the
formation of square-planar complexes. The Pt-Si dis-
˚
tance of 2.324(1) A is comparable to that observed for

5128 Organometallics, Vol. 28, No. 17, 2009
Mitton et al.
Complex 13 also features a characteristic set of 19F{1H}
NMR resonances (benzene-d6, 25 °C; -110.8 (d with Pt
satellites, 1 F, JFF = 33 Hz, 3JFPt=255 Hz), -112.1 (d with
unresolved Pt satellites, 1 F, JFF=38 Hz), -162.0 (m, 1 F),
-162.8 (m, 1 F), and -163.8 (m, 1 F) ppm) that correspond
to the inequivalent ortho-, para-, and meta-fluorine substit-
uents of the Pt-C6F5 group, in which rotation about the
Pt-C bond by 180° is slow on the NMR time scale at 25 °C.
However, unlike 6, the 19F{1H} NMR spectrum of 13 did not
change significantly in the range 25-80 °C (benzene-d6,
470.8 MHz), in keeping with the increased steric demand
of the [Cy-PSiP] ligand in 13 relative to [Ph-PSiP] in 6.
Figure 5. ORTEP diagram for 11 OEt2 shown with 50% dis-
placement ellipsoids; all H-atoms, as well as the diethyl ether
3
solvate, have been omitted for clarity. Selected interatomic
˚
distances (A) and angles (deg) for 11 OEt2: Pt-P1 2.2776(7);
3
Pt-P2 2.2808(7); Pt-Si 2.324(1); Pt-C2 2.139(2); P1-Pt-P2
162.41(2); Si-Pt-C2 175.13(5).
In an effort to prepare a Pt(II) hydride complex, 8 was
reacted with 1 equiv of LiEt3BH in THF solution at room
temperature (eq 5). Unlike the complex reactivity observed
for [Ph-PSiP]PtCl (1) under these conditions, 31P{1H} NMR
analysis of the reaction mixture revealed the quantitative
conversion of 8 to the new species 14 (76.6 ppm, s with Pt
satellites, 1JPPt=2908 Hz). Complex 14 was isolated in 92%
yield following workup. Solution NMR data for 14 support
the identification of this complex as a Cs-symmetric bis-
(phosphino) Pt derivative of [Cy-PSiP]H that features η2-Si-
H coordination involving the tethered silicon fragment.6b,23
In keeping with this formulation, the 1H NMR spectrum of
14 (benzene-d6) features a characteristic resonance at 5.48
ppm (t with Pt satellites, 1 H, JHPt=921 Hz, JHP=19 Hz),
which corresponds to the η2-Si-H fragment. Notably, this
resonance falls in the chemical shift region typically asso-
ciated with Si-H resonances of free silanes or metal silyl
species (ca. 3.0-6.0 ppm);6b no resonance that could be
attributed to a terminal Pt-H ligand was observed. The 29Si
NMR spectrum of 14 features a resonance with Pt satellites
at 62.3 ppm (JSiPt =735 Hz, JSiH = 52 Hz); this signal is
shifted downfield relative to the 29Si NMR resonance ob-
˚
2 CH2Cl2 (2.356(2) A) and falls within the range character-
3
istic of Pt-Si bond distances (2.255-2.444 A).6b The Pt-C2
˚
˚
bond distance of 2.139(2) A is significantly longer than that
˚
reported for (BQA)PtPh (Pt-CPh=2.023(4) A; BQA=bis(8-
quinolyl)amido),10 which is in agreement with the strong
trans-influence of Si.
Much like its [Ph-PSiP]PtMe analogue 3, complex 10
exhibited high thermal stability in benzene solution; no
reaction was observed upon heating a benzene solution of
10 at 90-100 °C over the course of several days. Further-
more, 10 did not react with an atmosphere of H2, even after
heating in benzene solution for 2 days at 80 °C. Treatment of
10 with 1 equiv of B(C6F5)3 in benzene solution cleanly
generated a new product (12) that was consistent with
methide abstraction in 10 to form {[Cy-PSiP]Pt}þ[MeB-
1
(C6F5)3]-, as indicated by H, 31P, and 11B NMR spectro-
scopy of the reaction mixture. Complex 12 was isolated in
87% yield and exhibits a characteristic, sharp 11B{1H} NMR
resonance at -14.0 ppm (benzene-d6) that is consistent with
the [MeB(C6F5)3]- anion. While the resonance for the B-Me
1
protons is obscured by P-Cy resonances in the H NMR
1
spectrum of 12 (benzene-d6), this signal was identified at 1.59
ppm by the use of 1H-13C HSQC correlation spectroscopy
(the B-Me 13C{1H} NMR resonance was observed as a broad
served for [Cy-PSiP]H (-24.2 ppm, JSiH = 210 Hz, ben-
zene-d6),5a which supports the presence of a Pt-Si bonded
1
interaction. The reduced JSiH value (typical JSiH values in
peak at 0.1 ppm in benzene-d6). Both the 31P (70.8 ppm, 1JPPt
=
free silanes fall near 200 Hz, while 1JSiH values in metal silyl
species range between ca. 140 and 220 Hz) observed for 14
falls in the range commonly associated with η2-silane com-
plexes.6b,23,24 Furthermore, in keeping with η2-Si-H coordi-
nation to a metal center, the IR spectrum of 14 (film) exhibits
a broad, intense band at 1808 cm-1, a region characteristic of
an η2-Si-H metal species.23d Although the monomeric nature
of 14 in solution cannot be unequivocally confirmed on the
1
3038 Hz, benzene-d6) and 29Si (22.9 ppm, JSiPt =971 Hz,
benzene-d6) NMR resonances of 12 are shifted substantially
relative to 10, and the increased value of 1JSiPt for 12 relative
to 10 is in keeping with methide abstraction (Table 2).
While the stability of 12 in benzene solution at room
temperature exceeds that of the [Ph-PSiP] variant 5, heating
a benzene solution of 12 at 100 °C for 48 h led quantitatively
to a new product (13, eq 4). As in the case of the [Ph-PSiP]Pt
analogue 6, compound 13 was identified on the basis of
NMR spectroscopic studies as a neutral Pt-C6F5 derivative
resulting from transfer of C6F-5 to Pt from B (eq 4). Complex
13 was isolated in 86% yield and features a 29Si NMR
resonance at 53.8 ppm that is shifted significantly downfield
relative to 12. The decreased value of 1JSiPt observed for 13
(806 Hz, relative to 971 Hz for 12) is consistent with the
proposed formulation of this complex, where a ligand with a
relatively strong trans-influence is coordinated trans to Si.
(23) (a) Kubas, G. J. Metal Dihydrogen and σ-Bond Complexes;
Kluwer Academic: New York, 2001. (b) Lin, Z. Chem. Soc. Rev. 2002,
31, 239. (c) Nikonov, G. Adv. Organomet. Chem. 2005, 53, 217. (d) Lachaize,
S.; Sabo-Etienne, S. Eur. J. Inorg. Chem. 2006, 2115.
(24) It has recently been suggested that, in the absence of independent
corroborating evidence, JSiH values < 70 Hz may not be a definitive
measure of the extent of Si-H interation: (a) Dubberley, S. R.; Ignatov,
S. K.; Rees, N. H.; Razuvaev, A. G.; Mountford, P.; Nikonov, G. I.
J. Am. Chem. Soc. 2003, 125, 642. (b) Ignatov, S. K.; Rees, N. H.; Tyrrell, B.
R.; Dubberley, S. R.; Razuvaev, A. G.; Mountford, P.; Nikonov, G. I.
Chem.;Eur. J. 2004, 10, 4991.

Article
Organometallics, Vol. 28, No. 17, 2009 5129
basis of the available NMR data, the steric demand of the
chelating [Cy-PSiP] ligand would appear to preclude poly-
nuclear variants of this complex.25 Support for the mono-
meric structure of 14 was also obtained from a low-
resolution X-ray crystallographic analysis of this compound
in which the Si-H position could not be located.26 In benzene
solution complex 14 reacted with 10 equiv of 1-hexene to give
ca. 50% conversion to a mixture of internal olefins upon
heating at 65 °C for 3 days (1H NMR). Throughout the
course of this reaction 14 was the only [Cy-PSiP]Pt species
observed in solution (1H and 31P NMR), with no evidence for
the formation of a hydrosilylated derivative.
Scheme 3. Reactivity of [R-PSiP]PtMe Complexes with Silanes
Despite the strong trans-directing abilities of both hydride
and silyl ligands, complexes of the type trans-Pt(PCy3)2(H)-
(SiH2R) (R = H, Cl, SiH3) have been previously reported by
Ebsworth and co-workers, who reacted trans-Pt(PCy3)2(H)2
with the corresponding silanes H3SiR to give the respective
Pt(II) silyl species upon elimination of H2.27 Related com-
plexes featuring trans geometries have also been formed by
the isomerization (photochemical or thermal, depending on
the substituents at Si) of the corresponding cis-Pt(PCy3)2-
(H)(SiR3) complexes.28 In this context, complex 14 can be
viewed as the product of “arrested” reductive elimination
from the unobserved Pt(II) hydrido silyl species [Cy-
PSiP]PtH.29 Such an elimination may proceed via an intra-
molecular twist of the type that has previously been invoked
for phosphine site exchange in cis-(R3P)2Pt(ER3)2 (E=Si or
Sn) complexes,30 which would serve to bring the hydride
ligand into the proximity of the Si in the [Cy-PSiP] ligand
backbone. Attempts to probe further the solution behavior
of 14 by variable-temperature 1H and 31P NMR spectrosco-
py (toluene-d8) revealed no appreciable changes in spectro-
scopic features in the range -80-90 °C. Interestingly, it has
been proposed that complexes of the type cis-Pt(PCy3)2(H)-
(SiR3) exhibit reversible reductive elimination-oxidative ad-
dition of silane via a putative η2-silane intermediate.28a,31
Reactivity of [R-PSiP]Pt(II) Complexes (R = Ph, Cy) with
Hydrosilanes. The reactivity of neutral [R-PSiP]PtR0 (R=
Ph, Cy; R0 = alkyl) complexes with hydrosilanes was ex-
plored in order to determine whether such complexes can
mediate Si-H bond cleavage reactions. Although neither the
benzyl complex 2 nor the methyl complexes 3 and 10 reacted
with an atmosphere of H2, these complexes reacted readily
with 1 equiv of PhSiH3 at room temperature in benzene
solution to form the corresponding silyl complexes [R-
PSiP]PtSiH2Ph (Scheme 3; 15, R = Ph; 16, R = Cy) with
concomitant elimination of either toluene or methane, re-
spectively (1H NMR). The formation of both 15 and 16 was
quantitative, as indicated by in situ 31P NMR spectroscopy
of the reaction mixtures, and both complexes were isolated as
analytically pure solids in 96% yield.
Compound 15 exhibits relatively broad 1H and 31P NMR
features. The 1H NMR spectrum of 15 (toluene-d8) at 27 °C
features a fairly sharp resonance at 4.95 ppm (t with Si and
unresolved Pt satellites, 2 H, 1JSiH=162 Hz, 3JHP = 5 Hz)
that corresponds to the Si-H protons of the Pt-SiH2Ph
group. The [Ph-PSiP] ligand SiMe protons are observed as
a broad singlet at 0.41 ppm under these conditions, and the
remaining aromatic protons of the ligand are observed as
broad overlapping resonances between 8.11 and 6.95 ppm.
At 27 °C, the 31P{1H} NMR spectrum of 15 (toluene-d8)
(25) For selected examples of conceptually related polynuclear spe-
cies in which Si is not part of a chelating ligand framework, see: (a)
Levchinsky, Y.; Rath, N. P.; Braddock-Wilking, J. Organometallics
1999, 18, 2583. (b) Braddock-Wilking, J.; Levchinsky, Y.; Rath, N. P.
Organometallics 2000, 19, 5500. (c) Braddock-Wilking, J.; Corey, J. Y.;
Trankler, K. A.; Xu, H.; French, L. M.; Praingam, N.; White, C.; Rath, N.
Organometallics 2006, 25, 2859. (d) Ciriano, M.; Green, M.; Howard, J. A.
K.; Proud, J.; Spencer, J. L.; Stone, F. G. A.; Tsipis, C. A. J. Chem. Soc.,
Dalton Trans. 1978, 801. (e) Sanow, L. M.; Chai, M.; McConville, D. B.;
Galat, K. J.; Simons, R. S.; Rinaldi, P. L.; Youngs, W. J.; Tessier, C. A.
Organometallics 2000, 19, 192.
features a broad singlet at 62.2 ppm with Pt satellites (1JPPt
=
2810 Hz). No diagnostic 29Si NMR data could be obtained
for this compound, despite prolonged acquisition times.
Variable-temperature 1H and 31P NMR studies (toluene-
d8 solution) were conducted in order to further investigate
the solution behavior of 15. At -80 °C, the 1H NMR
spectrum of 15 features broad resonances for the both the
˚
˚
˚
(26) Unit cell: a = 24.139 A; b = 22.383 A; c = 16.798 A; R = 90°; β =
94.692°; γ = 90°.
(27) Ebsworth, E. A.; Marganian, V. M.; Reed, F. J. S.; Gould, R. O.
J. Chem. Soc., Dalton Trans. 1978, 1167.
(28) (a) Chan, D.; Duckett, S. B.; Heath, S. L.; Khazal, I. G.; Perutz,
R. N.; Sabo-Etienne, S.; Timmins, P. L. Organometallics 2004, 23, 5744.
(b) Clark, H. C.; Ferguson, G.; Hampden-Smith, M. J.; Ruegger, H.; Ruhl, B.
L. Can. J. Chem. 1988, 66, 3120. (c) Grumbine, S. D.; Tilley, T. D. J. Am.
Chem. Soc. 1993, 115, 7884.
(29) Schubert, U. Adv. Organomet. Chem. 1990, 30, 151.
(30) (a) Obora, Y.; Tsuji, Y.; Nishiyama, K.; Ebihara, M.; Kawamura,
T. J. Am. Chem. Soc. 1996, 118, 10922. (b) Tsuji, Y.; Nishiyama, K.; Hori,
S.; Ebihara, M.; Kawamura, T. Organometallics 1998, 17, 507.
(31) For a related example involving phosphine site exchange in
(dcpe)Pd(SiR3)H (dcpe = Cy2PCH2CH2PCy2) complexes via Pd(η2-
Si-H) intermediates see: Boyle, R. C.; Mague, J. T.; Fink, M. J. J. Am.
Chem. Soc. 2003, 125, 3228.

5130 Organometallics, Vol. 28, No. 17, 2009
Mitton et al.
[Ph-PSiP] and SiH2Ph ligand protons. As the temperature is
raised to 27 °C, slight line-shape changes are observed in all
proton resonances; however, no significant coalescence phe-
nomena are observed. Above 27 °C, the Si-H protons of the
SiH2Ph ligand broaden with increasing temperature, while
most remaining proton resonances become sharp. At 90 °C,
the aromatic proton resonances are relatively well resolved
between 8.14 and 6.95 ppm, and the Si-Me protons of the Pt-
bound [Ph-PSiP] ligand are observed as a sharp singlet at
0.25 ppm with Pt satellites (3JHPt=10 Hz); the Si-H protons
are observed as a broad multiplet centered at 4.82 ppm. The
31P{1H} NMR spectrum of 15 was also recorded in the
-80-90 °C temperature range; although line broadening
was noted over this temperature range, no decoalescence
phenomena were observed, and neither the 31P NMR che-
silyl complex [Ph-PSiP]PtSiPh2Cl (17, 81% yield, Scheme 3)
with concomitant elimination of toluene (1H and 31P NMR);
similar reactivity was observed when using 3 in place of 2.
Complex 17 features two 29Si NMR resonances at 60.6
(1JSiPt = 1212 Hz) and 71.6 (1JSiPt = 556 Hz) ppm, which
correspond to the Pt-bound SiPh2Cl and [Ph-PSiP] ligands,
respectively. By comparison, the bulkier iPr2SiHCl does not
react with 2 even after heating the reaction mixture in
benzene at 80 °C for 4 days. Interestingly, the reaction of
10 with 1 equiv of Ph2SiHCl in benzene solution did not
result in the elimination of methane to form a new Pt silyl
complex. Rather, the formation of [Cy-PSiP]PtCl (8)
and concomitant evolution of Ph2SiMeH were observed
(Scheme 3). Within 10 min at room temperature, 25%
conversion of 10 to 8 and Ph2SiMeH was observed (1H and
31P NMR), and complete conversion was attained after
heating the reaction mixture at 80 °C for 24 h. Complex 10
1
mical shift nor the JPPt values for the [Ph-PSiP] ligand
phosphorus atoms were found to vary appreciably. While
these studies suggest that more than one dynamic process
may be occurring in solution over the temperature range
-80-90 °C, we are currently unable to comment definitively
on the nature of these phenomena in 15. At first glance, one
might envision invoking hindered rotation about the
Pt-SiH2Ph linkage; however, this is inconsistent with the
absence of 31P NMR decoalescence over these temperatures.
Although we are unable to definitively elucidate the solution
NMR behavior of this compound, further support for the
proposed connectivity in 15 is provided via the comprehen-
sive spectroscopic characterization of the analogous [Cy-
PSiP]PtSiH2Ph complex 16 (vide infra).
i
also reacted in a similar fashion with 1 equiv of Pr2SiHCl,
i
generating 8 and Pr2SiMeH; in benzene solution, 12%
conversion of 10 to 8 was observed within 10 min at room
temperature, and 90% conversion was attained after heating
the reaction mixture at 80 °C for 7 days. In addition, 10 also
reacted with 1 equiv of Me3SiCl to form 8 and Me4Si
quantitatively (1H and 31P NMR) after heating at 80 °C for
7 days. No [Cy-PSiP]Pt-containing intermediates were ob-
served by 31P NMR spectroscopy during the course of these
reactions. Whereas Si-H bond activation by electron-rich
metal centers is well precedented,6b Si-halide bond activa-
tion is comparatively rare.33 Although the mechanism for the
conversion of 10 into 8 upon exposure to a chlorosilane has
not been determined as of yet, a mechanism invoking direct
Si-Cl oxidative addition followed by Si-C reductive elim-
ination appears unlikely for the reactions involving hydrido-
chlorosilanes, as Si-H oxidative addition to Pt(II) is
anticipated to be preferred.33f Nonetheless, the divergent
reactivity exhibited by 2 and 10 reveals that changes in the
substitution at phosphorus in the [R-PSiP] ligand can
alter the course of reactions involving such substrates.
Complex 11 also reacted with 1 equiv of either Ph2SiHCl
or iPr2SiHCl in benzene to generate 8; however, these reac-
tions were significantly slower, with the Ph2SiHCl reaction
reaching 40% conversion after 8 days at 80 °C and the
iPr2SiHCl reaction reaching 23% conversion after 7 days at
80 °C (1H and 31P NMR).
By comparison with 15, the room-temperature 1H and 31
P
NMR features of 16 (benzene-d6) are sharp and well-re-
solved. The 1H NMR spectrum of 16 features a resonance at
1
6.01 ppm (t with Pt and Si satellites, 2 H, JSiH =152 Hz,
2JHPt=33 Hz, 3JHP = 4 Hz) for the Si-H protons of the Pt-
SiH2Ph group, as well as a singlet at 0.69 ppm (with
unresolved Pt satellites) that corresponds to the Si-Me group
of the [Cy-PSiP] ligand. The 31P{1H} NMR spectrum of 16
contains a singlet with Pt satellites at 66.4 ppm (1JPPt=2723
Hz). As expected, two 29Si NMR resonances are observed for
16 (benzene-d6) at 81.6 (1JSiPt=650 Hz) and 81.3 (1JSiPt
=
1
1067 Hz, JSiH = 152 Hz) ppm, corresponding to the [Cy-
PSiP] and SiH2Ph fragments, respectively. The IR spectra of
15 and 16 each exhibit a medium-intensity Si-H stretch at
2045 and 2018 cm-1, respectively, which corresponds to the
Pt-SiH2Ph group. On the basis of these data, complex 16
(and by analogy complex 15) is assigned as a square-planar
bis(phosphino)silyl Pt(II) phenylsilyl complex with the
SiH2Ph ligand coordinated trans to the [Cy-PSiP] ligand Si.
Although phosphino Pt(II) bis(silyl) complexes are known,
In contrast to 10 and 11, the η2-Si-H complex 14 reacted
with 1 equiv of either PhSiH3 or Ph2SiHCl in benzene
solution at room temperature to cleanly form the corre-
sponding Pt silyl complexes [Cy-PSiP]PtSiH2Ph (16) and
[Cy-PSiP]PtSiPh2Cl (18), with concomitant evolution of H2
(eq 6). Complex 18 was isolated in 92% yield and features
29Si NMR resonances at 74.9 (1JSiPt = 638 Hz) and 62.2
(1JSiPt=1357 Hz) ppm, which correspond to the Pt-bound
[Cy-PSiP] and SiPh2Cl ligands, respectively. Complex 14 did
most complexes of this type exhibit cis-coordination.6b
A
rare example of a crystallographically characterized Pt(II)
complex featuring trans-disposed silyl ligands has been
reported previously by Kim, Osakada, Yamamoto, and co-
workers.32 In the case of 15 and 16, the chelating nature of
the [R-PSiP] ligand likely enforces this unusual geometry.
The reaction of [R-PSiP]Pt alkyl species with hydrosilanes
appears to be sensitive to steric effects, as bulky secondary
silanes such as Mes2SiH2 do not react with either 2 or 10,
even after prolonged heating (80 °C, 2-3 days). However,
complex 2 reacted with 1 equiv of Ph2SiHCl at room
temperature in benzene solution to cleanly form the isolable
(33) (a) Yamashita, H.; Hayashi, T.; Kobayashi, T.; Tanaka, M.;
Goto, M. J. Am. Chem. Soc. 1988, 110, 4417. (b) Rappoli, B. J.; Janik, T. S.;
Churchill, M. R.; Thompson, J. S.; Atwood, J. D. Organometallics 1988, 7,
1939. (c) Zlota, A. A.; Frolow, F.; Milstein, D. Chem. Commun. 1989, 1826.
(d) Levy, C. J.; Puddephatt, R. J.; Vittal, J. J. Organometallics 1994, 13,
1559. (e) Levy, C. J.; Vittal, J. J.; Puddephatt, R. J. Organometallics 1996, 15,
2108. (f) Levy, C. J.; Puddephatt, R. J. J. Am. Chem. Soc. 1997, 119, 10127.
(g) Yamashita, H.; Tanaka, M.; Goto, M. Organometallics 1997, 16, 4696.
€
(h) Stohr, F.; Sturmayr, D.; Kickelbick, G.; Schubert, U. Eur. J. Inorg. Chem.
2002, 2305. (i) Yoo, H.; Carroll, P. J.; Berry, D. H. J. Am. Chem. Soc. 2006,
128, 6038. (j) Gatard, S.; Chen, C.-H.; Foxman, B. M.; Ozerov, O. V.
Organometallics 2008, 27, 6257.
(32) Kim, Y.-J.; Park, J.-I.; Lee, S.-C.; Osakada, K.; Tanabe, M.;
Choi, J.-C.; Koizumi, T.; Yamamoto, T. Organometallics 1999, 18, 1349.

Article
Organometallics, Vol. 28, No. 17, 2009 5131
not react with iPr2SiHCl upon heating at 80 °C for 3 days, but
did react with 1 equiv Me3SiCl to form 8, reaching approxi-
mately 80% conversion after 10 days of heating at 80 °C in
benzene solution (1H and 31P NMR).
sion of 10 and 11 into 8 upon exposure to a chlorosilane has not
been determined, the divergent reactivity observed for [Ph-
PSiP]- versus [Cy-PSiP]Pt(II) alkyl species reveals that mod-
ification of the steric and electronic properties of the [R-PSiP]
ligand directs the outcome of reactions with hydridochlorosi-
lanes toward either Si-H or net Si-Cl bond cleavage. Inter-
estingly, in contrast to 10 and 11, the η2-Si-H complex 14
reacted with 1 equiv of either PhSiH3 or Ph2SiHCl to produce
the corresponding Pt silyl complexes 16 and [Cy-PSiP]Pt-
SiPh2Cl (18), with concomitant evolution of H2.
Experimental Section
General Considerations. All experiments were conducted un-
der nitrogen in an MBraun glovebox or using standard Schlenk
techniques. Dry, oxygen-free solvents were used unless other-
wise indicated. All nondeuterated solvents were deoxygenated
and dried by sparging with nitrogen and subsequent passage
through a double-column solvent purification system purchased
from MBraun Inc. Tetrahydrofuran and diethyl ether were
purified over two activated alumina columns, while benzene,
toluene, and pentane were purified over one activated alumina
column and one column packed with activated Q-5. All purified
Summary and Conclusions
A new series of Pt(II) complexes featuring the tridentate
bis(phosphino)silyl ligands [κ3-(2-R2PC6H4)2SiMe]- ([R-
PSiP], R=Ph, Cy) were prepared and characterized, includ-
ing the first examples of alkyl and silyl Pt(II) complexes
supported by silyl pincer ligation. These studies have shown
that the [R-PSiP] ligand set can readily accommodate the
formation of square-planar Pt(II) complexes, including com-
plexes that feature strongly electron-donating ligands, such
as alkyl, aryl, and silyl, coordinated trans to Si. Surprisingly,
the reaction of [Cy-PSiP]PtCl with LiEt3BH did not result in
the formation of a terminal Pt-H, but rather the formation
of [Cy-PSi(μ-H)P]Pt (14) was observed. The formation of the
η2-Si-H complex 14 was unexpected given that complexes of
the type trans-Pt(PCy3)2(H)(SiR3) are known. Complex 14
can be viewed as the product of an “arrested” reductive
elimination from the unobserved Pt(II) hydride species [Cy-
PSiP]PtH.
˚
solvents were stored over 4 A molecular sieves. All deuterated
solvents were degassed via three freeze-pump-thaw cycles and
stored over 4 A molecular sieves. The compounds PtCl2(SEt2)2
˚
(Strem) and Li[B(C6F5)4](Et2O)2.5 (Boulder Scientific) were
purchased and used as received. Triethylamine was deoxyge-
nated and dried by sparging with nitrogen and subsequent
distillation from CaH2. The compounds (2-Ph2PC6H4)2SiH-
Me,5b (2-Cy2PC6H4)2SiHMe,5a and PhCH2K34 were prepared
according to literature procedures. Silanes were purchased from
Gelest, degassed via three freeze-pump-thaw cycles, and
˚
stored over 4 A molecular sieves. All other reagents were
purchased from Aldrich and used without further purification.
Unless otherwise stated, 1H, 13C, 31P, 11B, and 29Si NMR
characterization data were collected at 300 K on a Bruker AV-
500 spectrometer operating at 500.1, 125.8, 202.5, 160.5, and
99.4 MHz (respectively) with chemical shifts reported in parts
per million downfield of SiMe4 (for 1H, 13C, and 29Si),
Cationic species of the type {[R-PSiP]Pt}þ were also
prepared by either halide or alkyl anion abstraction routes,
utilizing Li[B(C6F5)4](OEt2)2.5 or B(C6F5)3, respectively.
Despite the precedent for arene C-H activation by cationic
Pt complexes, {[R-PSiP]Pt}þ species did not exhibit reactiv-
ity with benzene C-H bonds. Rather, complexes of the type
{[R-PSiP]Pt}þ[R0B(C6F5)3]- (R0 =Me, CH2Ph) underwent
B-C bond cleavage in the borate anion to form [R-PSiP]Pt-
(C6F5) and R0B(C6F5)2. Heating of [Cy-PSiP]PtX (X=Cl,
OTf) complexes in benzene solution in the presence of amine
bases also did not result in benzene C-H activation.
In an effort to further assess the reactivity of [R-PSiP]Pt-
(II) species with respect to E-H bond activation, reactions
with H2 and hydrosilanes were also carried out. Although
[R-PSiP]PtR0 (R0=Me, CH2Ph) complexes did not react with
an atmosphere of H2 even under forcing conditions, these
complexes reacted readily with an equivalent of PhSiH3 to
form the corresponding silyl species [R-PSiP]PtSiH2Ph
(R=Ph, 15; R=Cy, 16) with loss of R0H. By comparison,
[R-PSiP]PtR0 complexes exhibited divergent reactivity to-
ward hydridochlorosilanes based on the substitution at
phosphorus (R=Ph vs R=Cy). Thus, while [Ph-PSiP]PtR0
reacted with 1 equiv of Ph2SiHCl to form the silyl complex
[Ph-PSiP]PtSiPh2Cl (17) with loss of R0H, [Cy-PSiP]PtMe
(10) reacted with either Ph2SiHCl, iPr2SiHCl, or Me3SiCl to
form [Cy-PSiP]PtCl (8) with concomitant evolution of Ph2Si-
BF3 OEt2 (for 11B), or 85% H3PO4 in D2O (for 31P). Unless
3
otherwise stated, 19F NMR characterization data were collected
on a Bruker AC-250 spectrometer operating at 235.4 MHz with
chemical shifts reported in parts per million relative to a
standard sample of 0.5% CF3C6H5 in chloroform-d at -63.7
ppm. Variable-temperature NMR data were collected on a
Bruker AC-250 spectrometer. 1H and 13C NMR chemical shift
assignments are based on data obtained from 13C-DEPTQ,
1H-1H COSY, 1H-13C HSQC, and 1H-13C HMBC NMR
experiments. 29Si NMR assignments are based on 1H-29Si
HMQC and 1H-29Si HMBC experiments. 1H-29Si coupl-
ing constants were determined by the use of 1H-coupled 1H-29Si
HMQC and 1H-29Si HMBC experiments. 13C NMR reso-
nances associated with C6F5 fragments were not assigned.
In some cases, fewer than expected unique 13C NMR resonances
were observed, despite prolonged acquisition times. Elemental
analyses were performed by Canadian Microanalytical Service
Ltd. of Delta, British Columbia, Canada. Infrared spectra
were recorded as thin films between NaCl plates using a
Bruker VECTOR 22 FT-IR spectrometer at a resolution
of 4 cm-1
.
[Ph-PSiP]PtCl (1). A room-temperature solution of 1 (0.15 g,
0.27 mmol) in 5 mL of benzene was added to a slurry of
PtCl2(SEt2)2 (0.12 g, 0.27 mmol) in 3 mL of benzene. The
resulting clear yellow solution was allowed to stand at room
temperature for 16 h, over the course of which pale yellow
i
MeH, Pr2SiMeH, or Me4Si, respectively. The Pt phenyl
complex [Cy-PSiP]PtPh (11) also reacted with hydridochloro-
silanes to form 8; however, these reactions were significantly
slower relative to 10. Although the mechanism for the conver-
(34) Schlosser, M.; Hartmann, J. Angew. Chem., Int. Ed. Engl. 1973,
12, 508.

5132 Organometallics, Vol. 28, No. 17, 2009
Mitton et al.
microcrystals precipitated from solution. The supernatant solution
was removed by cannula, and the remaining crystalline residue
was washed with 3 ꢀ 3 mL of pentane and dried in vacuo to give
1 (0.20 g, 95%) as a pale yellow solid. Isolated 1 exhibited poor
solubility in a wide range of solvents, including benzene, acet-
one, CH2Cl2, CHCl3, THF, and CH3CN. 1H NMR (500 MHz,
chloroform-d): δ 8.19 (d, 2 H, Harom, JHH = 7 Hz), 7.78 (m, 4 H,
2JCP = 7 Hz, PtMe). 31P{1H} NMR (202.5 MHz, benzene-d6): δ
57.4 (s with Pt satellites, 1JPPt = 3012 Hz). 29Si NMR (99.4 MHz,
benzene-d6): δ 60.5 (with Pt satellites, JSiPt = 647 Hz). Anal.
Calcd for C38H34P2PtSi: C, 58.83; H, 4.42. Found: C, 58.81;
1
H, 4.41.
{[Ph-PSiP]Pt}þ[B(C6F5)3(CH2Ph)]- (4). A room-temperature
solution of 2 (0.14 g, 0.16 mmol) in ca. 7 mL of benzene was
treated with B(C6F5)3 (0.084 g, 0.16 mmol). The resulting homo-
geneous yellow solution was allowed to stand at room tempera-
ture for 20 min, over the course of which a colorless
microcrystalline precipitate was observed. The volatile compo-
nents were removed under vacuum, and the remaining residue was
washedwith2ꢀ 3mLofcold(-30 °C) pentane and dried in vacuo
to afford 4 as an off-white solid (0.20 g, 89% yield). 1H NMR (500
MHz, bromobenzene-d5): δ 8.00 (d, 2 H, Harom, J = 7 Hz),
H
arom), 7.60 (m, 4 H, Harom), 7.54 (m, 2 H, Harom), 7.46-7.39 (16
H, Harom), 0.16 (s with Pt satellites, 3 H, SiMe, 3JHPt = 24 Hz).
13C{1H} NMR (125.8 MHz, chloroform-d): δ 152.6 (apparent t,
J = 24 Hz, Carom), 142.5 (m, Carom), 134.3 (apparent t, J = 7 Hz,
CHarom), 134.0 (apparent t, J = 7 Hz, CHarom), 133.2 (CHarom),
133.1 (CHarom), 133.0 (CHarom), 132.5 (apparent t, J = 25 Hz,
Carom), 131.8 (apparent t, J = 28 Hz, Carom), 130.8 (CHarom),
130.7 (CHarom), 129.6 (br, CHarom), 129.0 (apparent t, J = 5 Hz,
CHarom), 128.4 (apparent t, J = 5 Hz, CHarom), 5.8 (s with Pt
7.41-7.16 (28 H, Harom), 6.96 (m, 2 H, Harom), 6.81 (t, 1 H, Harom
,
satellites, JCPt = 63 Hz SiMe). 31P{1H} NMR (202.5 MHz,
J = 7 Hz), 3.44 (s, 2 H, BCH2Ph), 0.35 (s with unresolved Pt
satellites, 3 H, SiMe). 13C{1H} NMR (125.8 MHz, bromoben-
zene-d5): δ 149.3 (BCH2Phipso), 148.1 (m, Carom), 133.9 (m,
CHarom), 133.1 (CHarom), 133.0 (CHarom), 132.9 (CHarom), 132.6
(CHarom), 132.4 (CHarom), 132.3 (CHarom), 132.1 (CHarom), 129.7
(CHarom), 129.3 (CHarom), 129.2 (CHarom), 127.2 (CHarom), 122.8
(CHarom), 32.4 (br, BCH2Ph), 6.0 (SiMe). 31P{1H} NMR (202.5
MHz, bromobenzene-d5): δ 48.1 (s with Pt satellites, 1JPPt = 3016
Hz). 29Si NMR (99.4 MHz, bromobenzene-d5): δ 26.6 (with Pt
satellites, 1JSiPt = 976 Hz). 11B{1H} NMR (160.5 MHz, bromo-
benzene-d5): δ -17.4. 19F{1H} NMR (235.4 MHz, 25 °C, bromo-
benzene-d5):δ-130.8 (d, 6 F, JFF = 20Hz, C6F5ortho), -164.3(m,
3 F, C6F5para), -166.9 (t, 6 F, JFF = 20 Hz, C6F5meta). Anal. Calcd
forC62H38BF15P2PtSi: C, 54.68; H, 2.81. Found: C, 54.98; H, 3.13.
2
chloroform-d): δ 51.7 (s with Pt satellites, 1JPPt = 3074 Hz). 29Si
NMR (99.4 MHz, chloroform-d): δ 35.6 (with Pt satellites, 1JSiPt
= 1110 Hz). Anal. Calcd for C37H31ClP2PtSi: C, 55.81; H, 3.92.
Found: C, 55.91; H, 3.90. Slow evaporation of a benzene
solution of 1 at room temperature provided a crystal suitable
for single-crystal X-ray diffraction analysis.
[Ph-PSiP]PtCH2Ph (2):. A room temperature slurry of 1 (0.32
g, 0.40 mmol) inca. 10 mL of THF was treated with solid KCH2Ph
(0.052 g, 0.40 mmol). The resulting orange-colored reaction
mixture was allowed to stir at room temperature for 20 min.
The volatile components of the reaction mixture were then
removed under vacuum, and the residue was extracted with ca.
10 mL of benzene. The benzene extracts were filtered through
Celite, and the filtrate was concentrated to dryness under vacuum
to afford 2 as a bright yellow solid (0.33 g, 97% yield). 1H NMR
(500 MHz, benzene-d6): δ 8.11 (d, 2 H, Harom, J = 7 Hz), 7.48 (m,
4 H, Harom), 7.41 (m, 4 H, Harom), 7.28 (m, 2 H, Harom), 7.20 (t, 2
A crystal of 4(OEt2) OEt2 suitable for single-crystal X-ray dif-
3
fraction studies was grown from a concentrated diethyl ether
solution of 4 at -30 °C.
Generation of {[Ph-PSiP]Pt}þ[B(C6F5)3Me]- (5). A room-
temperature solution of 3 (0.020 g, 0.026 mmol) in ca. 0.7 mL of
benzene-d6 was treated with B(C6F5)3 (0.013 g, 0.026 mmol) to
give a pale yellow homogeneous solution. The formation of 5 is
quantitative within 10 min of mixing, as indicated by in situ 1Hand
31P NMR spectroscopy. 1H NMR (500 MHz, benzene-d6): δ 7.68
(d, 2 H, Harom, J = 7 Hz), 7.54 (m, 2 H, Harom), 7.15-7.12 (6 H,
H, Harom, J = 7 Hz), 7.10-6.94 (16 H, Harom), 6.81 (t, 1 H, Harom
,
J = 7 Hz), 6.66 (d, 2 H, Harom, J = 7 Hz), 2.76 (t with Pt satellites,
2
3
2 H, PtCH2Ph, JHPt = 69 Hz, JHP = 6 Hz), 0.31 (s with Pt
satellites, 3 H, SiMe, 3JHPt = 9 Hz). 13C{1H} NMR (125.8 MHz,
benzene-d6): δ 155.4 (m, Carom), 147.3 (m, Carom), 135.2 (CHarom),
134.3 (CHarom), 132.9(m, CHarom), 132.3(m, Carom), 131.0-130.5
(overlapping resonances, CHarom), 129.4 (CHarom), 129.0
(CHarom), 120.7 (CHarom), 32.2 (s with Pt satellites, PtCH2Ph,
1JCPt = 428 Hz), 6.1 (s with Pt satellites, SiMe, 2JCPt = 38 Hz).
31P{1H} NMR (202.5 MHz, benzene-d6): δ 54.6 (s with Pt
satellites, 1JPPt = 3092 Hz). 29Si NMR (99.4 MHz, benzene-d6):
H
arom), 7.09-6.97 (18 H, Harom), 1.43 (s, 3 H, BMe), 0.19 (s with
Pt satellites, 3 H, SiMe, JHPt = 37 Hz). 13C{1H} NMR (125.8
MHz, benzene-d6): δ 147.5 (m, Carom), 141.8 (m, Carom), 134.8
(CHarom), 133.4 (CHarom), 132.7 - 132.3 (overlapping resonances,
CHarom), 131.3 (CHarom), 129.7 (CHarom), 129.3 (CHarom), 5.7
(SiMe), 4.4 (br, BMe). 31P{1H} NMR (202.5 MHz, benzene-d6): δ
56.3 (s with Pt satellites, 1JPPt = 3092 Hz). 29Si NMR (99.4 MHz,
benzene-d6): δ 30.4 (with Pt satellites, 1JSiPt = 1178 Hz). 11B{1H}
NMR (160.5 MHz, benzene-d6): δ -14.0. 19F{1H} NMR (235.4
MHz, 25 °C, benzene-d6): δ -132.2 (m, 6 F, C6F5ortho), -164.1 (m,
3 F, C6F5para), -166.9 (m, 6 F, C6F5meta).
3
1
δ 51.0 (with Pt satellites, JSiPt = 565 Hz). Anal. Calcd for
C44H38P2PtSi: C, 62.04; H, 4.50. Found: C, 61.49; H, 4.49. A
crystal of 2 CH2Cl2 suitable for single-crystal X-ray diffraction
studies was grown from a concentrated dichloromethane solution
of 2 at -30 °C.
3
[Ph-PSiP]PtMe (3). A precooled (-30 °C) slurry of 1 (0.15 g,
0.19 mmol) in ca. 8 mL of THF was treated with MeLi (0.12 mL,
1.6 M in Et2O, 0.19 mmol). The resulting reaction mixture was
allowed to stir at room temperature for 1 h. The volatile compo-
nents of the reaction mixture were then removed under vacuum,
and the residue was extracted with ca. 7 mL of benzene. The
benzene extracts were filtered through Celite, and the filtrate was
concentrated to dryness under vacuum to afford 3 as an off-white
solid (0.14 g, 95% yield). 1H NMR (500 MHz, benzene-d6): δ 8.21
(d, 2 H, Harom, J = 7 Hz), 7.76 (m, 4 H, Harom), 7.49 (m, 4 H,
[Ph-PSiP]Pt(C6F5) (6). A solution of 5 (generated from 3
according to the procedure detailed above, 0.077 mmol based
on the amount of 3 utilized) in ca. 3 mL of benzene was heated at
65 °C for 2 h. The volatile components were removed under
vacuum. The remaining residue was washed with 2 ꢀ 3 mL of cold
(-30 °C) pentane and dried in vacuo to afford 6 as an off-white
1
solid (0.067 g, 94% yield). H NMR (500 MHz, benzene-d6): δ
8.07 (d, 2 H, Harom, J = 7 Hz), 7.98 (m, 4 H, Harom), 7.39 (m, 2 H,
Harom), 7.21 (t, 2 H, Harom, J =7 Hz), 7.12 (m,4 H, Harom), 7.06 (t,
H
arom), 7.37 (m, 2 H, Harom), 7.24 (t, 2 H, Harom, J = 7 Hz),
4 H, Harom, J = 7 Hz), 7.02 - 6.97 (4 H, Harom), 6.90 (t, 2 H,
7.06-6.91 (14 H, Harom), 1.01 (t with Pt satellites, 3 H, PtMe,
3JHP = 5 Hz, 2JHPt = 52 Hz), 0.44 (s with unresolved Pt satellites,
3 H, SiMe). 13C{1H} NMR (125.8 MHz, benzene-d6): δ 156.2
(apparent t, J = 24 Hz, Carom), 146.2 (apparent t, J = 32 Hz,
Harom, J = 7 Hz), 6.81 (t, 4 H, Harom, J = 7 Hz), 0.43 (s with Pt
satellites, 3 H, SiMe, 3JHPt = 14 Hz). 13C{1H} NMR (125.8 MHz,
benzene-d6): δ 154.8 (apparent t, J = 25 Hz, Carom), 144.9
(apparent t, J = 32 Hz, Carom), 135.2 (m, CHarom), 134.3 (m,
CHarom), 133.2 - 132.9 (overlapping resonances, CHarom), 131.5
(CHarom), 131.3 (CHarom), 130.5 (CHarom), 129.9 (m, CHarom),
C
arom), 133.9 (apparent t, J = 11 Hz, CHarom), 133.6 - 133.4
(overlapping resonances, CHarom), 132.7 (CHarom), 130.1 (C-
arom), 129.8 (CHarom), 129.5 (CHarom), 128.5 (CHarom), 128.4
H
129.4 (apparent t, J = 5 Hz, CHarom), 128.5 (CHarom), 6.52
=
2
(s with Pt satellites, SiMe, JCPt
(apparent t, J = 5 Hz, CHarom), 127.8 (apparent t, J = 4 Hz,
CHarom), 6.2 (s with Pt satellites, SiMe, JCPt = 36 Hz), 3.6 (t,
45 Hz). 31P{1H}
2
NMR (202.5 MHz, benzene-d6): δ 54.0 (s with Pt satellites,

Article
Organometallics, Vol. 28, No. 17, 2009 5133
1JPPt = 2919 Hz). 29Si NMR (99.4 MHz, benzene-d6): δ 51.6 (with
Pt satellites, 1JSiPt = 813 Hz). 19F{1H} NMR (470.8 MHz, 25 °C,
benzene-d6): δ -113.2 (m, 1 F, C6F5ortho), -115.4 (m, 1 F,
C6F5ortho), -162.9 to -164.2 (overlapping resonances, 3 F,
C6F5meta and C6F5para). Anal. Calcd for C43H31F5P2PtSi: C,
55.66; H, 3.37. Found: C, 55.57; H, 3.36.
(0.060 g, 87% yield). 1H NMR (500 MHz, benzene-d6): δ 7.89 (d,
2 H, Harom, J = 7 Hz), 7.34 (m, 2 H, Harom), 7.23 (t, 2 H, Harom
,
J = 7 Hz), 7.13 (t, 2 H, Harom, J = 7 Hz), 2.98 (m, 2 H, PCH), 2.81
(m, 2 H, PCH), 2.50 (m, 2 H, PCy), 2.29 (m, 2 H, PCy), 1.78-0.85
(36 H, PCy), 0.71 (s with Pt satellites, 3 H, SiMe, 3JHPt = 24 Hz).
13C{1H} NMR (125.8 MHz, benzene-d6): δ 153.9 (apparent t, J =
21 Hz, Carom), 139.1 (apparent t, J = 26 Hz, Carom), 132.8
(apparent t, J = 10 Hz, CHarom), 132.2 (CHarom), 131.0
(CHarom), 129.6 (CHarom), 36.9 (apparent t, CHCy, J = 15 Hz),
36.5 (apparent t, CHCy, J = 13 Hz), 31.0 (CH2Cy), 29.8 (CH2Cy),
29.6 (CH2Cy), 29.4 (CH2Cy), 27.8 (m, CH2Cy), 27.5-27.1
(overlapping resonances, CH2Cy), 26.4 (CH2Cy), 7.6 (SiMe). 31P-
{1H} NMR (202.5 MHz, benzene-d6): δ 65.9 (s with Pt satellites,
1JPPt = 3055 Hz). 29Si NMR (99.4 MHz, benzene-d6): δ 18.8 (with
{[Ph-PSiP]Pt(OEt2)0.5}þ[B(C6F5)4]- (7(OEt2)0.5). A room-
temperature slurry of 1 (0.070 g, 0.088 mmol) in ca. 5 mL of
fluorobenzene was treated with Li[B(C6F5)4](OEt2)2.5 (0.077 g,
0.088 mmol). The resulting pale yellow colored solution was
allowed to stir at room temperature for 2 h. The reaction mixture
was filtered through Celite, and the filtrate was collected and dried
in vacuo. The remaining pale yellow oily residue was suspended in
ca. 5 mL of benzene and dried in vacuo to afford 7(OEt2)0.5 as a
paleyellow colored solid (0.12 g, 92% yield). Efforts tocompletely
remove the Et2O solvate from this isolated material in vacuo have
thus far been unsuccessful. NMR spectroscopic characterization
data (bromobenzene-d5 solution) for the isolated material are
consistent with the presence of half an equivalent of free Et2O that
is not coordinated to the Pt center. 1H NMR (500 MHz, bromo-
benzene-d5):δ8.01 (d, 2 H, Harom, J = 7 Hz), 7.41 (m,6 H, Harom),
7.32-7.17 (20 H, Harom), 0.36 (s with unresolved Pt satellites, 3 H,
SiMe). 13C{1H} NMR (125.8 MHz, bromobenzene-d5): δ 148.6
(Carom), 139.6 (Carom), 132.8 (m, CHarom), 132.0-131.8
(overlapping resonances, CHarom), 131.6 (CHarom), 131.3
(CHarom), 131.2 (CHarom), 131.0 (CHarom), 128.7 (CHarom),
128.2 (CHarom), 5.9 (SiMe). 31P{1H} NMR (202.5 MHz, bromo-
1
Pt satellites, JSiPt = 1381 Hz). 19F{1H} NMR (235.4 MHz,
benzene-d6): -77.9. Anal. Calcd for C38H55F3O3P2PtSSi: C,
48.87; H, 5.94. Found: C, 49.03; H, 6.43.
[Cy-PSiP]PtMe (10). A precooled (-30 °C) solution of 8 (0.18
g, 0.22 mmol) in ca. 5 mL of THF was treated with MeLi (1.6 M in
Et2O, 0.14 mL, 0.22 mmol). The resulting reaction mixture was
allowed to stand at room temperature for 20 min. The volatile
components of the reaction mixture were then removed under
vacuum, and the residue was extracted with ca. 10 mL of benzene.
The benzene extracts were filtered through Celite, and the filtrate
was concentrated to dryness under vacuum. The remaining resi-
due was washed with ca. 3 mL of cold (-30 °C) pentane and dried
under vacuum to afford 10 as a pale yellow solid (0.096 g, 55%
1
1
benzene-d5): δ 53.5 (s with Pt satellites, JPPt = 3009 Hz). 29Si
yield). H NMR (500 MHz, benzene-d6): δ 8.27 (d, 2 H, Harom
,
NMR (99.4 MHz, bromobenzene-d5): δ 32.2 (with Pt satellites,
1JSiPt = 1216 Hz). 11B{1H} NMR (160.5 MHz, benzene-d6): δ
-15.9. 19F{1H} NMR (470.8 MHz, bromobenzene-d5): δ -132.1
(s,8 F, C6F5ortho), -162.6 (apparent t, 4 F, JFF =24Hz, C6F5para),
J = 7 Hz), 7.57 (m, 2 H, Harom), 7.34 (t, 2 H, Harom, J = 7 Hz),
7.22 (t, 2 H, Harom, J = 7 Hz), 2.83 (m, 2 H, PCH), 2.55 (m, 2 H,
PCH), 2.27 (br d, 2 H, PCy, J = 13 H), 2.06 (m, 2 H, PCy),
1.78-0.83 (39 H, PCy þ PtMe, overlapping resonances; the PtMe
resonance was identified at 1.25 ppm by the use of correlation
spectroscopy), 0.74 (s with unresolved Pt satellites, 3 H, SiMe).
13C{1H} NMR (125.8 MHz, benzene-d6): δ 160.3 (apparent t, J =
22 Hz, Carom), 144.4 (apparent t, J = 26 Hz, Carom), 134.1
(apparent t, J = 10 Hz, CHarom), 131.4 (CHarom), 130.3
(CHarom), 128.9 (CHarom), 38.0 (apparent t, CHCy, J = 13 Hz),
37.3 (apparent t, CHCy, J = 15 Hz), 30.3 (CH2Cy), 29.6 (CH2Cy),
29.2 (CH2Cy), 28.1-27.0 (overlapping resonances, CH2Cy), 26.5
(CH2Cy), 9.2 (SiMe), -1.6 (t, 2JCP = 8 Hz, PtMe). 31P{1H} NMR
(202.5 MHz, benzene-d6): δ 57.9 (s with Pt satellites, 1JPPt = 2938
Hz). 29Si NMR (99.4 MHz, benzene-d6): δ 63.9 (with Pt satellites,
1JSiPt = 696 Hz). Anal. Calcd for C38H58P2PtSi: C, 57.05; H, 7.31.
Found: C, 56.62; H, 7.34.
-166.3 (s, 8 F, C6F5meta). Anal. Calcd for C61H31BF20P2PtSi
3
(OEt2)0.5: C, 51.24; H, 2.46. Found: C, 51.39; H, 2.69.
[Cy-PSiP]PtCl (8). A room-temperature solution of [Cy-
PSiP]H (0.34 g, 0.57 mmol) in 5 mL of benzene was added to a
slurry of PtCl2(SEt2)2 (0.25 g, 0.57 mmol) in 5 mL of benzene. The
reaction mixture was then treated with Et3N (0.080 mL, 0.058 g,
0.57 mmol), and the resulting solution was transferred to a thick-
walled glass reaction vessel equipped with a Teflon stopcock. The
pale yellow reaction mixture was subsequently heated at 65 °C for
30 h, over the course of which a white precipitate was observed.
The reaction mixture was allowed to cool to room temperature
and was filtered to afford a clear, pale yellow solution. The volatile
components of the filtrate solution were removed under vacuum
to afford8 as an off-white solid (0.41 g, 86% yield). 1H NMR (500
MHz, benzene-d6): δ 8.07 (d, 2 H, Harom, J = 7 Hz), 7.46 (m, 2 H,
[Cy-PSiP]PtPh (11). A precooled (-30 °C) solution of 8 (0.070
g, 0.085 mmol) inca. 5mLofTHFwas treatedwithPhLi(1.8 Min
nBu2O, 47.4 μL, 0.085 mmol). The resulting reaction mixture was
allowed to stand at room temperature for 20 min. The volatile
components of the reaction mixture were then removed under
vacuum, and the residue was extracted with ca. 10 mL of benzene.
The benzene extracts were filtered through Celite, and the filtrate
was concentrated to dryness under vacuum to afford 11 as a
yellow solid (0.069 g, 94% yield). 1H NMR (500 MHz, benzene-
d6): δ 8.27 (d, 2 H, Harom, J = 7 Hz), 7.96 (br d with Pt satellites,
Harom), 7.29 (t, 2 H, Harom, J = 7 Hz), 7.17 (t, 2 H, Harom, J = 7
Hz), 3.32 (m, 2 H, PCH), 2.56 (m, 2 H, PCH), 2.36 (m, 2 H, PCy),
2.28 (m, 2 H, PCy), 2.09 (m, 2 H, PCy), 1.76-1.32 (24 H, PCy),
1.26-0.78 (10 H, PCy), 0.72 (s with Pt satellites, 3 H, SiMe,
3JHPt = 26 Hz). 13C{1H} NMR (125.8 MHz, benzene-d6): δ 156.6
(apparent t, J = 22 Hz, Carom), 141.3 (apparent t, J = 26 Hz,
Carom), 133.3 (apparent t, J = 10 Hz, CHarom), 131.7 (CHarom),
130.7 (CHarom), 129.3 (CHarom), 37.3 (apparent t, CHCy, J = 14
Hz), 37.0 (apparent t, CHCy, J = 15 Hz), 30.2 (CH2Cy), 29.9
(CH2Cy), 29.2 (CH2Cy), 28.0 (CH2Cy), 27.4 (m, CH2Cy), 27.1
(CH2Cy), 26.3 (CH2Cy), 8.2 (s with Pt satellites, 2JCPt = 56 Hz,
SiMe). 31P{1H} NMR (202.5 MHz, benzene-d6): δ 59.4 (s with Pt
satellites, 1JPPt = 2984 Hz). 29Si NMR (99.4 MHz, benzene-d6):
2 H, PtPhortho,
3JHPt = 37 Hz), 7.55 - 7.47 (overlapping
resonances, 4 H, Harom þ PtPhmeta), 7.33 (t, 2 H, Harom, J = 7
Hz), 7.20 (t, 2 H, Harom, J = 7 Hz), 7.13 (t, 1 H, PtPhpara, J = 7
Hz), 2.81 (m, 2 H, PCH), 2.44 (m, 2 H, PCH), 1.92 (m, 4 H, PCy),
1.73-0.91 (36 H, PCy), 0.71 (s with Pt satellites, 3 H, SiMe,
3JHPt = 11 Hz). 13C{1H} NMR (125.8 MHz, benzene-d6): δ 177.8
(apparent t, J = 10 Hz, PtCipso), 159.7 (apparent t, J = 22 Hz,
1
δ 32.3 (with Pt satellites, JSiPt = 1183 Hz). Anal. Calcd for
C37H55ClP2PtSi: C, 54.17; H, 6.76. Found: C, 54.09; H, 6.60.
[Cy-PSiP]PtOTf (9). A room-temperature solution of 8 (0.061
g, 0.074 mmol) in ca. 5 mL of benzene was treated with a slurry of
AgOTf (0.019 g, 0.074 mmol) in ca. 3 mL of benzene. A white
precipitate was observed upon mixing. The resulting reaction
mixture was allowed to stir at room temperature for 45 min.
The cloudy solution was then filtered through Celite to give a
clear, colorless solution. The volatile components of the filtrate
solution were removed under vacuum to afford 9 as a white solid
Carom), 143.5 (apparent t, J = 26 Hz, Carom), 142.2 (br s, Pt-
Phortho), 134.0 (apparent t, J = 10 Hz, CHarom), 131.5 (CHarom),
130.5 (CHarom), 128.7 (CHarom), 127.9 (br s, PtPhmeta), 122.4
(PtPhpara), 37.9 (apparent t, CHCy, J = 14 Hz), 35.2 (apparent t,
CHCy, J = 15 Hz), 30.6 (m, CH2Cy), 29.8 (CH2Cy), 28.7-27.4
(overlapping resonances, CH2Cy), 26.8 (d, CH2Cy, J = 8 Hz),
2
9.5 (s with Pt satellites, JCPt = 31 Hz, SiMe). 31P{1H} NMR
(202.5 MHz, benzene-d6): δ 56.2 (s with Pt satellites, 1JPPt = 2921

5134 Organometallics, Vol. 28, No. 17, 2009
Mitton et al.
Hz). 29Si NMR (99.4 MHz, benzene-d6): δ 59.7 (with Pt satellites,
1JSiPt = 646 Hz). Anal. Calcd for C43H60P2PtSi: C, 59.91; H, 7.02.
Found: C, 59.97; H, 6.96. A crystal of 11 OEt2 suitable for single-
crystal X-ray diffraction studies was grown from a concentrated
diethyl ether solution of 11 at -30 °C.
1.65-0.75 (overlapping resonances, 33 H, PCy þ SiMe; the SiMe
resonance was identified at 0.96 ppm by the use of correlation
spectroscopy). 13C{1H} NMR (125.8 MHz, benzene-d6): δ 160.0
(apparent t, J = 22 Hz, Carom), 143.9 (apparent t, J = 22 Hz,
3
Carom), 134.5 (apparent t, J = 10 Hz, CHarom), 131.3 (CHarom),
{[Cy-PSiP]Pt}þ[B(C6F5)3Me]- (12). A room-temperature so-
lution of 10 (0.070 g, 0.088 mmol) in ca. 5 mL of benzene was
treated with B(C6F5)3 (0.045 g, 0.088 mmol). The resulting
homogeneous yellow solution was allowed to stand at room
temperature for 12 h. The volatile components were then removed
under vacuum, and the remaining residue was washed with 2 ꢀ 3
mL of cold (-30 °C) pentane and dried in vacuo to afford 12 as a
yellow solid (0.10 g, 87% yield). 1H NMR (500 MHz, benzene-d6):
δ 7.68 (d, 2 H, Harom, J = 7 Hz), 7.17-7.12 (overlapping
resonances, 4 H, Harom), 7.07 (t, 2 H, Harom, J = 7 Hz), 2.54
(m, 2 H, PCH), 2.32 (m, 2 H, PCH), 2.06 (br d, 2 H, PCy, J = 11
Hz), 1.90 (br d, 2 H, PCy, J = 11 Hz), 1.63-0.80 (37 H, PCy þ
BMe, overlapping resonances; the BMe resonance was identified
at 1.59 ppm by the use of correlation spectroscopy), 0.83 (m, 2 H,
PCy), 0.60 (s, 3 H, SiMe). 13C{1H} NMR (125.8 MHz, benzene-
d6): δ 150.4 (br m, Carom), 136.6 (br m, Carom), 132.5 (apparent t,
J = 9 Hz, CHarom), 132.3 (CHarom), 131.7 (CHarom), 130.4
(CHarom), 37.5-37.2 (overlapping resonances, CHCy), 31.0
(CH2Cy), 30.3 (CH2Cy), 30.0 (CH2Cy), 29.5 (CH2Cy), 27.3-27.0
(overlapping resonances, CH2Cy), 26.6 (CH2Cy), 26.2 (CH2Cy), 7.7
(SiMe), 0.1 (br, BMe). 31P{1H} NMR (202.5 MHz, benzene-d6): δ
70.8 (s with Pt satellites, 1JPPt = 3038 Hz). 29Si NMR (99.4 MHz,
benzene-d6): δ 22.9 (with Pt satellites, 1JSiPt = 971 Hz). 11B{1H}
NMR (160.5 MHz, benzene-d6): δ -14.0. 19F{1H} NMR (235.4
MHz, 25 °C, benzene-d6): -132.3 (d, 6 F, JFF = 20 Hz, C6F5ortho),
-162.8 (apparent t, 3 F, JFF = 22 Hz, C6F5para), -166.3 (apparent
t, 6 F, JFF = 21 Hz, C6F5meta). Anal. Calcd for C56H58BF15P2PtSi:
C, 51.27; H, 4.46. Found: C, 50.50; H, 4.70.
130.5 (CHarom), 128.7 (CHarom), 38.7 (apparent t, CHCy, J = 13
Hz), 35.1 (apparent t, CHCy, J = 17 Hz), 32.3 (CH2Cy), 29.6 (m,
CH2Cy), 29.0-27.1 (overlapping resonances, CH2Cy), 26.6
(CH2Cy), 9.1 (s with Pt satellites, 2JCPt = 33 Hz, SiMe). 31P{1H}
NMR (202.5MHz, benzene-d6):δ76.6(swithPtsatellites,1JPPt
=
2908 Hz). 29Si NMR (99.4 MHz, benzene-d6): δ 62.3 (with Pt
satellites, JSiPt = 735 Hz, JSiH = 52 Hz). IR (film, cm-1): 1808 (br
m, M-H). Anal. Calcd for C37H56P2PtSi: C, 56.54; H, 7.18. Found:
C, 56.35; H, 7.11.
[Ph-PSiP]PtSiH2Ph (15). A room-temperature solution of 2
(0.20 g, 0.24 mmol) in ca. 8 mL of benzene was treated with
PhSiH3 (0.025 g, 29.0 μL, 0.24 mmol). The resulting reaction
mixture was allowed to stand at room temperature for 16 h. The
volatile components were then removed under vacuum to afford
15 as a pale yellow solid (0.20 g, 96% yield). Compound 15
1
exhibits temperature-dependent H and 31P NMR line shapes;
representative data acquired at 27, 90, and -80 °C are provided.
No diagnostic 13C or 29Si NMR data could be obtained for this
compound by use of 1D or 2D NMR techniques, despite pro-
longed acquisition times. Although we are unable to comment
definitively regarding the solution NMR behavior of 15, further
support for the proposed connectivity in this compound is
provided via the comprehensive spectroscopic characterization
ofthe analogous[Cy-PSiP]PtSiH2Ph complex (16). 1H NMR(250
MHz, 27 °C, toluene-d6): δ 8.11 (br d, 2 H, Harom, J = 7 Hz), 7.53
(m, 4 H, Harom), 7.37 (br s, 4 H, Harom), 7.26-7.19 (6 H, Harom),
7.03 - 6.95 (17 H, Harom), 4.95 (t with Si satellites and unresolved
Pt satellites, 2 H, PtSiH2Ph, 1JSiH = 162 Hz, 3JHP = 5 Hz), 0.41
(br s, 3 H, SiMe). 1H NMR (250 MHz, -80 °C, toluene-d6): δ 8.01
(br d, 2 H, Harom, J = 7 Hz), 7.53 (m, 4 H, Harom), 7.30-6.97
(broad overlapping resonances, 23 H, Harom), 6.74 (m, 4 H,
[Cy-PSiP]Pt(C6F5) (13). A solution of12 (0.051 g, 0.039 mmol)
in ca. 5 mL of benzene was heated at 100 °C for 48 h. The volatile
components were removed under vacuum. The remaining residue
was washed with 2 ꢀ 3 mL of cold (-30 °C) pentane and dried in
vacuo to afford 13 as an off-white solid (0.032 g, 86% yield). 1H
NMR (500 MHz, benzene-d6): δ 8.14 (d, 2 H, Harom, J = 7 Hz),
7.44 (m, 2 H, Harom), 7.32 (t, 2 H, Harom, J = 7 Hz), 7.18 (t, 2 H,
H
arom), 5.28 (br t, 2 H, PtSiH2Ph, 3JHP = 5 Hz), 0.59 (br s, 3 H,
1
SiMe). H NMR (250 MHz, 90 °C, toluene-d6): δ 8.14 (d, 2 H,
Harom, J = 7 Hz), 7.56 (m, 4 H, Harom), 7.36 (m, 4 H, Harom),
7.27-7.20 (4 H, Harom), 7.12 (br s, 4 H, Harom), 7.07-6.95 (15 H,
Harom), 4.82 (br m, 2 H, PtSiH2Ph), 0.25 (s with Pt satellites, 3 H,
Harom, J = 7 Hz), 2.56 (m, 2 H, PCH), 2.37 (m, 2 H, PCH), 1.97
3
(br d, 2 H, PCy, J = 14 Hz), 1.85 (br d, 2 H, PCy, J = 14 Hz),
1.56-0.72 (36 H, PCy), 0.57 (s with Pt satellites, 3 H, SiMe,
3JHPt = 16 Hz). 13C{1H} NMR (125.8 MHz, benzene-d6): δ 158.1
(apparent t, J = 22 Hz, Carom), 141.4 (apparent t, J = 26 Hz,
SiMe, JHPt = 10 Hz). 31P{1H} NMR (101.3 MHz, 27 °C,
1
benzene-d6): δ 62.2 (br s with Pt satellites, JPPt = 2810 Hz).
31P{1H} NMR (101.3 MHz, -80 °C, benzene-d6): δ 61.4 (s with Pt
satellites, 1JPPt = 2787 Hz). 31P{1H} NMR (101.3 MHz, 90 °C,
benzene-d6): δ 62.2(s withPtsatellites, 1JPPt = 2807 Hz). IR (film,
cm-1): 2045 (br m, Si-H). Anal. Calcd for C43H38P2PtSi2: C,
59.50; H, 4.41. Found: C, 59.16; H, 4.40.
Carom), 133.7 (apparent t, J = 10 Hz, CHarom), 131.5 (CHarom),
131.1 (CHarom), 129.1 (CHarom), 37.8-37.5 (overlapping reso-
nances, CHCy), 30.2-26.6 (overlapping resonances, CH2Cy),
9.4 (SiMe). 31P{1H} NMR (202.5 MHz, benzene-d6): δ 60.1 (s
[Cy-PSiP]PtSiH2Ph (16). A room-temperature solution of 10
(0.050 g, 0.063 mmol) in ca. 5 mL of benzene was treated with
PhSiH3 (0.007 g, 7.7 μL, 0.063 mmol). The resulting reaction
mixture was allowed to stand at room temperature for 18 h. The
volatile components were then removed under vacuum to afford
16 as a pale yellow solid (0.054 g, 96% yield). 1H NMR (500 MHz,
benzene-d6): δ 8.23 (d, 2 H, Harom, J = 7 Hz), 8.04 (d, 2 H,
SiPhortho, J = 7 Hz), 7.56 (m, 2 H, Harom), 7.33 (t, 2 H, Harom, J =
7 Hz), 7.29 (t, 2 H, SiPhmeta, J = 7 Hz), 7.21 (t, 2 H, Harom, J =
7 Hz), 7.16 (t, 1 H, SiPhpara, J = 7 Hz), 6.01 (t with Pt and Si
1
with Pt satellites, JPPt = 2919 Hz). 29Si NMR (99.4 MHz,
benzene-d6): δ 53.8 (with Pt satellites, JSiPt = 806 Hz). 19F{1H}
NMR (470.8 MHz, 25 °C, benzene-d6): -110.8 (d with Pt
satellites, 1 F, JFF = 33 Hz, 3JFPt = 255 Hz, C6F5ortho), -112.1
(d with unresolved Pt satellites, 1 F, JFF = 38 Hz, C6F5ortho),
-162.0 (m, 1 F, C6F5para), -162.8 (m, 1 F, C6F5meta), -163.8 (m,
1 F, C6F5meta).
[Cy-PSi(μ-H)P]Pt (14). A precooled (-30 °C) solution of 8
(0.10 g, 0.12 mmol) in ca. 5 mL of THF was treated with LiEt3BH
(1.0 M in THF, 0.12 mL, 0.12 mmol). The resulting tan-colored
reaction mixture was allowed to stand at room temperature for
20 min. The volatile components of the reaction mixture were then
removed under vacuum, and the residue was extracted with ca. 10
mL of benzene. The benzene extracts were filtered through Celite,
and the filtrate was concentrated to dryness under vacuum to
afford 14 as an off-white solid (0.087 g, 92% yield). 1H NMR (500
MHz, benzene-d6): δ 8.25 (d, 2 H, Harom, J = 7 Hz), 7.47 (m, 2 H,
satellites, 2 H, PtSiH2Ph, 1JSiH = 152 Hz, 2JHPt = 33 Hz, 3JHP
=
4 Hz), 2.85 (m, 2 H, PCH), 2.54 (m, 2 H, PCH), 2.08-2.01 (4 H,
PCy), 1.82-1.58 (6 H, PCy), 1.58-0.78 (overlapping resonances,
30 H, PCy), 0.69 (s, 3 H, SiMe). 13C{1H} NMR (125.8 MHz,
benzene-d6): δ 158.6 (apparent t, J = 22 Hz, Carom), 148.4 (Si-
Phipso), 144.5 (apparent t, J = 24 Hz, Carom), 137.5 (SiPhortho),
133.9 (apparent t, J = 10 Hz, CHarom), 132.0 (CHarom), 130.8
(CHarom), 128.8 (CHarom), 127.9 (SiPhmeta), 127.0 (SiPhpara), 39.1
(apparent t, CHCy, J = 17 Hz), 37.5 (apparent t, CHCy, J = 17
Hz), 31.2 (CH2Cy), 30.1-29.3 (overlapping resonances, CH2Cy),
27.8-27.2 (overlapping resonances, CH2Cy), 26.6 (CH2Cy), 9.9
(SiMe). 31P{1H} NMR (202.5 MHz, benzene-d6): δ 66.4 (s with Pt
H
arom), 7.33 (t, 2 H, Harom, J = 7 Hz), 7.19 (t, 2 H, Harom, J =
=
7Hz), 5.48(twithPtsatellites, 1 H, Pt-H-Si, JHPt =921 Hz, JHP
19 Hz), 2.63 (m, 2 H, PCy), 2.39 (m, 2 H, PCy), 2.30-2.23 (4 H,
PCy), 2.00 (br d, 2 H, J = 12 Hz, PCy), 1.86 (br s, 4 H, PCy),

Article
Organometallics, Vol. 28, No. 17, 2009 5135
satellites, 1JPPt = 2723 Hz). 29Si NMR (99.4 MHz, benzene-d6): δ
and 11 (OEt2)2, while SADABS (Bruker) was used for 1(AlCl3)
3
3
1
81.6 (with Pt satellites, JSiPt = 650 Hz, SiMe), 81.3 (with Pt
(C6H5F)2. All structures were solved by use of the Patterson
satellites, 1JSiPt = 1067 Hz, 1JSiH = 152 Hz, SiH2Ph). IR (film,
cm-1): 2018 (br m, Si-H). Anal. Calcd for C43H62P2PtSi2: C,
57.89; H, 7.00. Found: C, 57.78; H, 7.09.
search/structure expansion and were refined by use of full-
matrix least-squares procedures (on F2) with R1 based on Fo2 g
2σ(F2o) and wR2 based on F2o g -3σ(F2o). Anisotropic displace-
ment parameters were employed for all the non-hydrogen atoms
[Ph-PSiP]PtSiPh2Cl (17). A room-temperature solution of 2
(0.15 g, 0.18 mmol) in ca. 10 mL of benzene was treated with
Ph2SiHCl (0.039 g, 34.5 μL, 0.18 mmol). The resulting reaction
mixture was allowed to stand at room temperature for 18 h. The
volatile components were then removed under vacuum, and the
remaining residue was washed with 2 ꢀ 3 mL of pentaneand dried
in vacuo to afford 17 as a pale yellow solid (0.14 g, 81% yield). 1H
NMR (500 MHz, benzene-d6): δ 8.07 (d, 2 H, Harom, J = 7 Hz),
7.85 (m, 4 H, Harom), 7.29 (d, 4 H, Harom, J = 7 Hz), 7.17-7.11
(overlapping resonances, 8 H, Harom), 7.04 (m, 4 H, Harom),
6.99-6.96 (overlapping resonances, 6 H, Harom), 6.90-6.85
(overlapping resonances, 6 H, Harom), 6.77 (t, 4 H, Harom), 0.29
(s, 3 H, SiMe). 13C{1H} NMR (125.8 MHz, benzene-d6): δ 153.0
(apparent t, J = 24 Hz, Carom), 149.1 (apparent t, J = 31 Hz,
of 1. During the structure solution process for 1(AlCl3) -
3
(C6H5F)2, 2 equiv of fluorobenzene were located in the asym-
metric unit. Disorder involving these solvent molecules was
identified during refinement. The fluorine substituent (F1S) in
one molecule of fluorobenzene was modeled in a satisfactory
manner over two half-occupied positions. In a second molecule
of fluorobenzene, the fluorine substituent (F2S) was modeled
over three positions with occupancies of 0.3, 0.4, and 0.3,
respectively. The carbon atoms in this fluorobenzene molecule
(C21s, C22S, C23S, C24S, C25S, and C26S) were modeled in a
satisfactory manner over two positions with occupancies of 0.6
and 0.4, respectively. Carbon atom positions for this solvent
molecule were refined with a common isotropic displacement
parameter, while fluorine atom positions were refined with an
isotropic displacement parameter 120% of that for the carbon
atoms. Anisotropic displacement parameters were employed for
Carom), 148.2 (m, Carom), 136.3 (CHarom), 135.8 (m, CHarom),
134.2-134.0 (overlapping resonances, CHarom), 133.2 (CHarom),
131.2 (CHarom), 130.3 (CHarom), 129.8 (CHarom), 129.0 (CHarom),
128.1 (CHarom), 127.6 (CHarom), 127.2 (CHarom), 7.6 (SiMe).
31P{1H} NMR (202.5 MHz, benzene-d6): δ 55.5 (s with Pt
satellites, 1JPPt = 2823 Hz). 29Si NMR (99.4 MHz, benzene-d6):
δ 60.6 (with Pt satellites, 1JSiPt = 1212 Hz, SiPh2Cl), 71.6 (with Pt
all remaining non-hydrogen atoms for 1(AlCl3) (C6H5F)2. The
3
Flack absolute structure parameter (-0.009(4)) confirmed that
the correct absolute structure of 1(AlCl3) (C6H5F)2 was chosen.
During the structure solution process for 2 CH2Cl2, two crystal-
3
3
1
satellites, JSiPt = 556 Hz, SiMe). Anal. Calcd for C49H41ClP2-
PtSi2: C, 60.15; H, 4.22. Found: C, 60.03; H, 4.19.
lographically independent molecules of [Ph-PSiP]PtCH2Ph (A
and B) along with 2 equiv of dichloromethane were located in
the asymmetric unit; for convenience, only molecule A is
discussed in the text. Disorder involving the benzyl ligand
(C2B, C3B, C4B, C5B, C6B, C7B, and C8B) in molecule B
was identified during the solution process. The carbon atoms of
the disordered benzyl ligand were refined isotropically over
two positions, where C2B-C8B were refined with an occupancy
factor of 0.65, while C2C-C8C were refined with an occupancy
factor of 0.35. Bond distances involving the methylene carbon
(C2B) of the disordered benzyl group were constrained to
[Cy-PSiP]PtSiPh2Cl (18). A room-temperature solution of 14
(0.10 g, 0.13 mmol) in ca. 5 mL of benzene was treated with
Ph2SiHCl (0.028 g, 24.9 μL, 0.13 mmol). The resulting reaction
mixture was allowed to stand at room temperature for 16 h. The
volatile components were then removed under vacuum to afford
18 as a pale yellow solid (0.12 g, 92% yield). 1H NMR (500 MHz,
benzene-d6): δ 8.21 (d, 2 H, Harom, J = 7 Hz), 8.13 (d, 4 H,
SiPhortho, J = 7 Hz), 7.53 (m, 2 H, Harom, J = 7 Hz), 7.32 (t, 2 H,
H
H
arom, J = 7 Hz), 7.26 (t, 4 H, SiPhmeta, J = 7 Hz), 7.18 (t, 2 H,
arom, J = 7 Hz), 7.13 (m, 2 H, SiPhpara), 3.06 (m, 2 H, PCH), 2.30
˚
be equal (within 0.01 A) during refinement: d(Pt1B-
(m, 2 H, PCH), 2.08 (m, 2 H, PCy), 1.74-0.90 (overlapping
resonances, 36 H, PCy), 0.76 (s with unresolved Pt satellites, 3 H,
SiMe), 0.72 (m, 2 H, PCy). 13C{1H} NMR (125.8 MHz, benzene-
d6): δ 157.5 (apparent t, J = 22 Hz, Carom), 151.7 (SiPhipso), 143.3
(apparent t, J = 24 Hz, Carom), 136.4 (SiPhortho), 133.8 (apparent
t, J = 10 Hz, CHarom), 132.9 (CHarom), 130.9 (CHarom), 128.7
(CHarom), 128.3 (SiPhpara), 127.9 (SiPhmeta), 39.8 (apparent t, J =
16 Hz, CHCy), 37.9 (apparent t, J = 14 Hz, CHCy), 32.3 (CH2Cy),
30.5-30.0 (overlapping resonances, CH2Cy), 27.9-26.1 (over-
lapping resonances, CH2Cy), 9.7 (SiMe). 31P{1H} NMR (202.5
MHz, benzene-d6): δ 65.8 (s with Pt satellites, 1JPPt = 2710 Hz).
29Si NMR (99.4 MHz, benzene-d6): δ 74.9 (with Pt satellites,
1JSiPt = 638 Hz, SiMe), 62.2 (with Pt satellites, 1JSiPt = 1357 Hz,
SiPh2Cl). Anal. Calcd for C49H65ClP2PtSi2: C, 58.69; H, 6.53.
Found: C, 58.53; H, 6.67.
C2B) = d(Pt1B-C2C); d(C2B-C3B) = d(C2C-C3C). The
phenyl rings of the conformers for this disordered group were
refined as idealized hexagons, with a C-C bond distance of
˚
1.39 A. Anisotropic displacement parameters were employed for
all remaining non-hydrogen atoms of molecule B as well as all
non-hydrogen atoms of molecule A. Structural disorder invol-
ving the dichloromethane solvate was also noted during the
refinement process for 2 CH2Cl2; this disorder was treated in a
3
satisfactory manner by employing a model featuring one fully
occupied formula unit and two half-occupied formula units of
dichloromethane within the asymmetric unit. Anisotropic dis-
placement parameters were employed for all the non-hydrogen
atoms of the solvent molecules, with the exception of one-half-
occupied formula unit of dichloromethane (Cl5S, Cl6S,
and C3S), which was refined isotropically. During the structure
Crystallographic Solution and Refinement Details for 1, 1-
(AlCl3) (C6H5F)2, 2 CH2Cl2, 4(OEt2) OEt2, and 11 (OEt2)2.
solution process for 4(OEt2) OEt2, 2 equiv of diethyl ether
3
were located in the asymmetric unit; 1 equiv of diethyl ether
is coordinated to the Pt center, while a second equivalent is
not. Disorder involving the solvent molecule that is not bound to
Pt (O1SA, C1SA, C2SA, C3SA, and C4SA) was identified
and subsequently modeled in a satisfactory manner over
two half-occupied positions. The pairs of atoms (O1SA,
O1SB), (C1SA, C1SB), (C2SA, C2SB), (C3SA, C3SB), and
3
3
3
3
Crystallographic data for 1 were obtained at 173((2) K, while
data for each of 1(AlCl3) (C6H5F)2 and 2 CH2Cl2 were ob-
3
3
tained at 193((2) K on a Bruker PLATFORM/SMART 1000
CCD diffractometer using graphite-monochromated Mo KR
˚
(λ=0.71073 A) radiation, employing a sample that was mounted
in inert oil and transferred to a cold gas stream on the diffract-
ometer. Crystallographic data for each of 4(OEt2) OEt2 and
11 (OEt2)2 were obtained at 173((2) K on a Bruker D8/APEX
(C4SA, C4SB) were each refined with a common iso-
3
tropic displacement parameter. Anisotropic displacement para-
meters were employed for all remaining non-hydrogen atoms
for 4(OEt2) OEt2. During the structure solution process
3
II CCD diffractometer using graphite-monochromated Mo KR
˚
(λ=0.71073 A) radiation, employing a sample that was mounted
3
in inert oil and transferred to a cold gas stream on the diffract-
ometer. Programs for diffractometer operation, data collection,
and data reduction (including SAINT) were supplied by Bruker.
Gaussian integration (face-indexed) was employed as the absorp-
tion correction method for 1, 2 CH2Cl2, 4(OEt2) OEt2,
for 11 (OEt2)2, 1 equiv of diethyl ether was located in the
3
asymmetric unit and refined in a satisfactory manner. Anisotropic
displacement parameters were employed for all the non-hydrogen
atoms of 11 (OEt2)2. In all cases, hydrogen-atoms were added
3
at calculated positions and refined by use of a riding model
3
3

5136 Organometallics, Vol. 28, No. 17, 2009
Mitton et al.
employing isotropic displacement parameters based on the
isotropic displacement parameter of the attached atom.
Additional crystallographic information is provided in the depo-
sited CIF.
Research and Innovation Trust Fund, and Dalhousie
University for their generous support of this work. We
also thank Dr. Michael Lumsden (NMR3, Dalhousie) for
his assistance in the acquisition of NMR data.
Acknowledgment. We are grateful to the Natural
Sciences and Engineering Research Council (NSERC)
of Canada (including a Discovery Grant for L.T.), the
Canada Foundation for Innovation, the Nova Scotia
Supporting Information Available: Crystallographic data
for 1, 1(AlCl3) (C6H5F)2, 2 CH2Cl2, 4(OEt2) OEt2, and 11
(OEt2)2 (CIF). This material is available free of charge via the
3
3
3
3
Internet at http://pubs.acs.org.