Base-Stabilized 1-Silacyclopenta-2,4-dienylidenes

Two novel carbenc-stabilized silacyclopentadieny-lidenes have been obtained via dehydrohalogenation of the corresponding hydrochlorosilole with N-heterocyclic carbenes THF at low temperature. The hose-stabilized cyclic carbon substituted silylenes are highly nucleophilic, as exemplified by the nucleophilic attack phenylacetylene to give a luminescent 1-alkenyl-1-alkynylsilole with the liberation of the coordinated carbene.