The copper(ii)-catalyzed and oxidant-promoted regioselective C-2 difluoromethylation of indoles and pyrroles

Chem Commun (Camb). 2020 Jul 25;56(58):8119-8122. doi: 10.1039/d0cc03345f. Epub 2020 Jun 17.

Abstract

A novel and efficient approach for the highly selective C-2 difluoromethylation of indole derivatives was developed by using sodium difluoromethylsulfinate (HCF2SO2Na) as the source of difluoromethyl groups and a Cu(ii) complex as the catalyst. Various substrates were well tolerated in this transformation and the desired products were obtained in moderate to good yields. Moreover, the late-stage C-2 difluoromethylation of bioactive molecules containing an indole ring was achieved in good yields. Generally, this reaction features excellent functional group compatibility, broad substrate scope and excellent C-2 selectivity.