Copyright 2009
Volume 28, Number 9, May 11, 2009
American Chemical Society
Communications Steric and Electronic Effects in Half-Sandwich Ruthenium Silane σ-Complexes with Si-H and Si-Cl Interligand Interactions† Dmitry V. Gutsulyak,‡ Andrei V. Churakov,§ Lyudmila G. Kuzmina,§ Judith A. K. Howard,| and Georgii I. Nikonov*,‡ Chemistry Department, Brock UniVersity, 500 Glenridge AVenue, St Catharines L2S 3A1, Ontario, Canada, Institute of General and Inorganic Chemistry RAS, Leninskii Prosp. 31, 119991 Moscow, Russia, and Chemistry Department, UniVersity of Durham, South Road, Durham DH1 3LE, U.K. ReceiVed December 17, 2008 Summary: The Cp ring is found to exert a primarily electronic effect on the strength of Si-H interaction in silane σ-complexes Cp(Pri3P)RuCl(η2-HSiClR2). Complexation of chlorosilanes HSiClR2 is supported by an additional RuCl · · · SiCl interaction. Transition-metal silane σ-complexes1,2 are of significant current interest, due to their proposed intermediacy in catalytic transformations of organosilicon compounds.1-3 The majority of structurally characterized silane σ-complexes show isolated η2- or η3-HnSiR4-n moieties:4 i.e., without additional (secondary) * To whom correspondence should be addressed. Tel: (905)6885550 ext. 3350. Fax: (905)9328846. E-mail: gnikonov@ brocku.ca. † Dedicated to the memory of Prof. Robert Bau. ‡ Brock University. § Institute of General and Inorganic Chemistry RAS. | University of Durham. (1) For recent discussions of nonclassical Si. .H interligand interactions, see: (a) Nikonov, G. I. AdV. Organomet. Chem. 2005, 53, 217–309. (b) Lin, Z. Chem. Soc. ReV. 2002, 31, 239. (c) Corey, J. Y.; Braddock-Wilking, J. Chem. ReV. 1999, 99, 175. (2) For a more general discussion of nonclassical interligand bonding see: (a) Kubas, G. J. Metal Dihydrogen and σ-Bond Complexes; Kluwer Academic/Plenum: New York; 2001. (b) Crabtree, R. H. Angew. Chem., Int. Ed. Engl. 1993, 32, 789. (3) Only in a few cases were silane σ-complexes established as precursors or intermediates in hydrosilylation. See, for instance: (a) Lachaize, S.; Sabo-Etienne, S.; Donnadieu, B.; Chadret, B. Chem. Commun. 2003, 214. (b) Yang, J.; White, P. S.; Brookhart, M. J. Am. Chem. Soc. 2008, 130, 17509.
interactions of the silane ligand with nearby ligands. However, there is mounting evidence of the involvement of such interligand interactions in transformations of σ-coordinated silanes without complete oxidative addition of the Si-H bond.5-7 In particular, Sabo-Etienne et al. suggested the occurrence of secondary interactions between hydride and silane ligands (as (4) η3-coordination has been reported recently: (a) Thomas, C. M.; Peters, J. C. Angew. Chem., Int. Ed. 2006, 45, 776–780. (b) Atheaux, I.; Donnadieu, B.; Daran, J.-C.; Sabo-Etienne, S.; Chaudret, B.; Hussein, K.; Barthelat, J.-C. J. Am. Chem. Soc. 2000, 122, 5664–5665. (5) (a) Lachaize, S.; Sabo-Etienne, S. Eur. J. Inorg. Chem. 2006, 2115. (b) Lachaize, S.; Caballero, A.; Vendier, L.; Sabo-Etienne, S. Organometallics 2007, 26, 3713–3721. (6) Perutz, R.; Sabo-Etienne, S. Angew. Chem., Int. Ed. 2007, 46, 2578– 2592. (7) Related interactions between η2-dihydrogen ligands and other ligands (hydrides, halides, etc.) are well-known: (a) Barrio, P.; Esteruelas, M. A.; Lledo`s, A.; On˜ate, E.; Toma`s, J. Organometallics 2004, 23, 3008. (b) Van der Sluys, L. S.; Eckert, J.; Eisenstein, O.; Hall, J. H.; Huffman, J. C.; Jackson, S. A.; Koetzle, T. F.; Kubas, G. J.; Vergamini, P. J.; Caulton, K. G. J. Am. Chem. Soc. 1990, 113, 4831. (8) Osipov, A. L.; Vyboishchikov, S. F.; Dorogov, K. Y.; Kuzmina, L. G.; Howard, J. A. K.; Lemenovskii, D. A.; Nikonov, G. I. Chem. Commun. 2005, 3349. (9) Deglmann, P.; Ember, E.; Hofmann, P.; Pitter, S.; Walter, O. Chem. Eur. J. 2007, 13, 2864. (10) (a) Osipov, A. L.; Gerdov, S. M.; Kuzmina, L. G.; Howard, J. A. K.; Nikonov, G. I. Organometallics 2005, 24, 587. (b) Duckett, S. B.; Kuzmina, L. G.; Nikonov, G. I. Inorg. Chem. Commun. 2000, 3/3, 126. (c) Gutsulyak, D. V.; Osipov, A. L.; Kuzmina, L. G.; Howard, J. A. K.; Vyboishchikov, S. F.; Nikonov, G. I. Dalton Trans. 2008, 6843.
10.1021/om801192b CCC: $40.75 2009 American Chemical Society Publication on Web 04/08/2009
2656 Organometallics, Vol. 28, No. 9, 2009
Communications
Scheme 1. Preparation of Silane σ-Complexes 4a-e
Table 1. Selected Spectroscopic Parameters in Complexes 4a-d and 2a-c,e
J(Si-H) (Hz) in 2 J(Si-H) (Hz) in 4 ν(SiHRu) (cm-1) in 4
SiCl3 (a)
SiMeCl2 (b)
SiMe2Cl (c)
SiH2Ph (d)
SiMe2Ph (e)
