Divergent synthesis of difluoromethylated indole-3-carbinols, bisindolylmethanes and indole-3-methanamines

Org Biomol Chem. 2023 Dec 20;22(1):90-94. doi: 10.1039/d3ob01735d.

Abstract

Indole-3-carbinol, bisindolylmethanes (BIMs) and indole-3-methanamines exhibit diverse therapeutic activities. Fluorinated molecules are widely used in pharmaceuticals. Herein we report a facile and straightforward method for the successful synthesis of difluoromethylated indole-3-carbinols, bisindolylmethanes and indole-3-methanamines by a Friedel-Crafts reaction. The reaction involves the in situ generation of difluoroacetaldehyde from difluoroacetaldehyde ethyl hemiacetal in the presence of a base or an acid. This protocol is distinguished by its good to excellent yields, broad substrate compatibility, good functional group tolerance and scalability.