Taking Advantage of the Ambivalent Reactivity of Ynamides in Gold Catalysis: A Rare Case of Alkyne Dimerization

Abstract

A gold mine of results: A series of ynamides have been dimerized in the presence of a gold(I) complex. This unprecedented transformation involves the formation of a key keteniminium intermediate that reacts to form a variety of cyclic and acyclic products. The substitution pattern of the ynamide determines which product is formed (see scheme; EWG=electron-withdrawing group, Ts=p-toluenesulfonyl).