9 - Silylenes, Silylaminosilylene, Disilane, Silanimine, Silacyclohexadienones, Bis(silyl)-Alkenes, and Hydrosilanimine

Abstract

Silylenes, divalent silicon compounds with the formula R2Si, are important intermediates in silicon chemistry. Like carbenes, silylenes are potentially useful as ligands in coordination chemistry and catalysis (1). Transient silylenes can be generated from a suitable tetravalent silicon compound either at high temperatures or under photochemical conditions. Alkali metal reduction of substituted silicon dihalides have been generally employed for the synthesis of stable silylenes. The first stable N-heterocyclic silylene was reported by West and co-workers in 1994 (2). Since then, several types of silylenes with different substituents were prepared by alkali metal reduction (3). In this experiment, the synthesis of an N-heterocyclic silylene by dehydrohalogenation of the corresponding hydrochlorosilane with N-heterocyclic carbenes is described (4). This new synthetic protocol allowed the synthesis of the N-heterocyclic silylene in high yields under mild and metal-free conditions and can be applied for the synthesis of various N-heterocyclic silylenes.