Metal-free synthesis of 3-chalcogen benzo[b]furans via an iodine-mediated electrophilic cyclisation of 2-alkynylanisoles

An efficient and metal-free method was developed to synthesize 3-chalcogen benzo[b]furans via the iodine-mediated electrophilic cyclisation of 2-alkynylanisoles with disulfides or diselenides. In the presence of I2, various 3-sulfenylbenzofurans or 3-selenenylbenzofurans were obtained in moderate to high yields.