Dehydrochlorination to Silylenes by N-Heterocyclic Carbenes

Reaction of cyclic diaminochlorosilanes with 1,3-bis(tert-butyl)imidazol-2-ylidene resulted in the facile formation of the corresponding stable and transient diaminosilylenes. This novel dehydrochlorination route could be applied for the generation of four- and five-membered N-heterocyclic silylenes with a range of different substituents under very mild conditions. Activation of an olefinic C-H bond and reduction of a cyclic diaminochlorosilane have been observed for these new transient silylenes.