Reactions of transition-metal ions with methylsilanes in the gas phase. The formation and characteristics of strong transition metal-silylene bonds

Journal Article · Wed Sep 17 04:00:00 EDT 1986 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00279a002· OSTI ID:5279347

Kang, H; Jacobson, D B; Shin, S K; Beauchamp, J L; Bowers, M T

Reactions of transition-metal ions (Ti/sup +/, V/sup +/, Cr/sup +/, Fe/sup +/, Co/sup +/, and Ni/sup +/) with organosilanes are investigated in the gas phase with an ion beam apparatus. Co/sup +/ and Ni/sup +/ react with silane to yield metal silylenes as exothermic products. Collision-induced dissociation studies of the product CoSiH/sub 2//sup +/ and nascent CoSiH/sub 4//sup +/ adducts provide additional information concerning the product structure and reaction mechanisms. Reactions with methylsilanes lead to formation and metal silylenes as major reaction channels, along with several other processes including hydride abstraction, dehydrogenation, and methane loss. Reactions with hexamethyldisilane are also investigated, with major products indicating Si-Si bond cleavage. An examination of the reaction enthalpies for the observed metal silylene products provides estimates for metal ion-silylene bond energies, which include D/sup 0/(M/sup +/ - SiH/sub 2/) = 67 +/- 6 kcal mol/sup -1/ (M = Co, Ni). Correlation between the metal ion-silylene bond energies and the electronic structure of the metal ions supports a bonding scheme in which silylene donates its nonbonding lone pair electrons to an empty 4s orbital of the metal center. For Co/sup +/ and Ni/sup +/, back-donation of paired 3d electrons from the metal into the empty 3p orbital on silicon is suggested to account for the stronger bond deduced for these metals.

• Research Organization: California Institute of Technology, Pasadena
• OSTI ID: 5279347
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 108:19; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400301* -- Organic Chemistry-- Chemical & Physicochemical Properties-- (-1987)
ALKANES
BINDING ENERGY
CATIONS
CHARGED PARTICLES
CHEMICAL BONDS
CHEMICAL REACTIONS
CHROMIUM
COBALT
COLLISIONS
DATA
ELECTRONIC STRUCTURE
ELEMENTS
ENERGY
ENERGY LEVELS
EXPERIMENTAL DATA
FLUIDS
GASES
HYDRIDES
HYDROCARBONS
HYDROGEN COMPOUNDS
INFORMATION
ION COLLISIONS
ION-MOLECULE COLLISIONS
IONS
IRON
METALS
MOLECULE COLLISIONS
NICKEL
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC SILICON COMPOUNDS
SILANES
SILICON COMPOUNDS
THERMODYNAMICS
TITANIUM
TRANSITION ELEMENTS
VANADIUM