Gold-catalyzed cascade cyclization of N-propargyl ynamides: rapid access to functionalized indeno[1,2-c]pyrroles

Abstract

A new gold-catalyzed cascade cyclization of N-propargyl ynamides involving a presumable vinyl cation intermediate has been developed, which allows the efficient and practical synthesis of various functionalized indeno[1,2-c]pyrroles in moderate to good yields under mild reaction conditions. Importantly, an unusual regioselective cyclization on the β-carbon of the ynamide was observed in such a gold-catalyzed alkyne–ynamide cyclization.