This paper describes the synthesis, structural characterization, and reactivity of the first stable 1-stannavinylidene-NHC complex, that is, a neutral monomeric compound with a C = Sn π-bond, which is a heavier group-14 analogue of vinylidene. The vinylidene-type character of the molecule was confirmed by spectroscopic means, X-ray diffraction analysis, theoretical calculations, and a reactivity study.

Abstract

The first stable 1-stannavinylidene-NHC complex with bulky silyl substituents has been obtained from the retro-dimerization of cyclic 1,3-bis(stannylene) with an N-heterocyclic carbene (NHC). To accomplish the retro-dimerization of cyclic 1,3-bis(stannylene), a suitably sized NHC is required. Both in the solid state and in solution, 1-stannavinylidene-NHC complex is characterized by the presence of a C = Sn π bond. When treated with SnCl₂, 1-stannavinylidene-NHC complex undergoes an addition reaction to afford the corresponding stable gem-bis(chlorostannylene).