Synthesis, Structure, and Reactivity of an NHC Silyl Gold(I) Complex

The first example of a silyl gold(I) complex stabilized by an N-heterocyclic carbene (NHC) was synthesized and fully characterized, including crystallographically. The syn insertion of methyl propiolate into the Au-Si bond leading to a vinyl gold complex is reported. As substantiated by X-ray diffraction analysis, the reaction proceeds with opposite regioselectivity compared with that previously observed with phosphine silyl gold(I) complexes.