US EPA

561452 

Journal Article 

Activation of the SiH bond of silanes in photochemical reactions with W(CO)6: Hydrosilylation of ketones and dehydrosilylation of alcohol by H2SiPh2 

Gadek, A; Szymanska-Buzar, T 

2006 

1 

Polyhedron
ISSN: 02775387 

25 

6 

1441-1448 

10.1016/j.poly.2005.10.002 

WOS:000236698900024 

Photolysis of W(CO)6 in the presence of H2SiPh2, H2SiEt2, and HSiEt3 in n-heptane leads to SiH bond activation and to the formation of a WH bond. In photochemical reaction of W(CO)6 with HSiEt3 in cyclohexane-d12, [eta]2-coordination of the SiH bond to the tungsten atom and the existence of a two-electron, three-centre SiH...W bond is supported by 1H NMR spectroscopy due to the detection of high-field resonance at [delta]H -8.58 (heptet, 3JHH = 1.6 Hz, 1JWH = 35 Hz, 1JSiH = 89 Hz). The photochemically activated W(CO)6 was tested as a catalyst in the hydrosilylation of ketones, RR'CO (R = Me, R' = Me, iPr, nPr, Ph), by diphenylsilane. The same activation of the SiH bond of H2SiPh2 by tungsten(0) was applied in dehydrogenative silylation of 2-propanol and in transformation of H2SiPh2 to disiloxane Ph2HSiOSiHPh2 in the presence of water. The products of these reactions (organosilicon compounds) were characterized by GC-MS and NMR spectroscopy. 

Tungsten; Silane; Si-H activation; Hydrosilylation; Hydride