Oxidative Aromatic C−O Bond Formation: Synthesis of 3-Functionalized Benzo[<i>b</i>]furans by FeCl₃-Mediated Ring Closure of α-Aryl Ketones

Abstract

A variety of 3-functionalized benzo[b]furans were achieved by way of a FeCl(3)-mediated intramolecular cyclization of electron-rich alpha-aryl ketones. The alkoxy substituent on the benzene ring in the substrates was essential for an efficient cyclization to occur. This novel method allows the construction of benzo[b]furan rings by joining the O-atom on the side chain to the benzene ring via direct oxidative aromatic C-O bond formation.