1,2-Silyl Rearrangement in Gold Carbene Chemistry: Synthesis of Furyl-Decorated Tetrasubstituted Silylallene Derivatives.

The gold-catalyzed reaction of 2-en-4-ynones with alkynylsilanes provides fully substituted allene derivatives bearing furyl and silyl groups. This transformation would involve generation of a gold furyl carbene intermediate, which regioselectively undergoes a nucleophilic attack by the alkynylsilane at the electrophilic carbene carbon atom with the formation of a β-gold vinyl cation species. The subsequent release of the gold catalyst, accompanied by a 1,2-silyl shift, leads to the formation of tetrasubstituted allene products.