Tungstate-Catalyzed Bioinspired Decarboxylative Halogenation of Electron-Deficient (Hetero)Phenolic Acids

Abstract

Phenolic acids (PAs) can be derived from lignin, and their value-added transformations provide a good renewable source for arenes. The halogenase-catalyzed decarboxylative halogenation of PAs is a key step in the biosynthesis of many halogenated natural products. Inspired by halogenase, herein we present a synthetically useful tungstate-catalyzed decarboxylative halogenation of electron-deficient (hetero)phenolic acids under mild conditions, based on which the antibiotic bromophene and its analogues were prepared concisely. Mechanism studies support the halogenation–decarboxylation procedure, but the decarboxylation–halogenation pathway cannot be excluded. Additionally, the chloride can reverse the selectivity between bromination and iodination in this reaction, somehow providing a useful perspective for the halide selectivity in vanadium-dependent haloperoxidase in seawater.