Lewis Acid-Mediated Regioselective Hydrofunctionalization of Styrenes with Isatins and Heterocycles

Abstract

The ligand-free Lewis acid-mediated regioselective hydroamination and hydroarylation of styrenes have been successfully developed in the presence of isatins or heterocyclic aryl compounds such as benzothiophenes and benzofurans. The reactions tolerate a variety of functional groups and afford the corresponding products in moderate to good yields. Deuterium labeling experiments show that the functionalized hydrogen of styrenes was derived from the nitrogen–hydrogen of the substrates in the hydroamination. Preliminary mechanistic studies suggest that the reactions may be a radical or a carbocation process.