Synthesis of 2,3‐Disubstituted Benzofurans by the Palladium‐Catalyzed Coupling of 2‐Iodoanisoles and Terminal Alkynes, Followed by Electrophilic Cyclization: 3‐Iodo‐2‐phenylbenzofuran

Abstract

The benzo[b]furan nucleus is prevalent in a wide variety of biologically active natural and unnatural compounds. The article describes the preparation of 3‐iodo‐2‐phenylbenzofuran which illustrates a general protocol for the palladium/copper‐catalyzed cross‐coupling of various o‐iodoanisoles and terminal alkynes, followed by electrophilic cyclization with I2. This approach to 2,3‐disubstituted benzofurans is very versatile. The substituents attached to the triple bond can be vinylic groups or aromatic rings bearing certain types of functionality.