CO hydrosilylation catalyzed by an N-heterocyclic carbene (NHC)-stabilized stannyliumylidene.

The di-N-heterocyclic carbene (NHCs) stabilized stannyliumylidene, [TerSn(IMe)][BArF], (Ter = 2,6-MesCH, Mes = 2,4,6-Me-CH, IMe = 1,3,4,5-tetramethylimidazol-2-ylidene, BArF = (3,5-(CF)-CH)B), was isolated from the reaction of (Ter)SnCl with two equivalents of IMe, followed by one equivalent of Na[BArF]. This stannyliumylidene acts as a precatalyst for the homogeneous hydrosilylation of CO. Experimental mechanistic studies and quantum chemical calculations have been conducted to elucidate the catalytically active species and the mechanism for the transformation, revealing the stannyliumylidene [TerSn(COIMe)][BArF], which is formed in the presence of CO, as the catalytically active species.