Direct α-Chalcogenation of Aliphatic Carboxylic Acid Equivalents.

A novel approach to α-chalcogenation of aliphatic carboxylic acids has been developed by means of transforming them as the corresponding benzazoles. The catalyst system, consisting of CuI, DMSO, and a base, operates through a unique mechanism to access a range of practically significant thio- and selenoethers that are otherwise challenging to achieve. The applicative potentials have been exemplified by utilizing the resultant chalcogenated compounds as the precursor for the synthesis of biologically pertinent molecules and synthetic intermediates.