Ligand-Free Copper-Catalyzed One-Pot Synthesis of Indole-2-carboxylic Esters

摘要

A simple, efficient, and facile synthetic route for the preparation of indole-2-carboxylic esters was described. The cascade reactions of 2-bromobenzaldehyde and glycine ester hydrochloride were promoted by Cu_ 2O and a base to provide the corresponding products in good yields. Commercially available, inexpensive substrates and reagents were employed under mild reaction conditions in this one-pot operation, which is complementary to existing methods for access to 2-substituted indoles.