Visible‐Light‐Induced Trifluoromethylation of Isonitrile‐Substituted Indole Derivatives: Access to 1‐(Trifluoromethyl)‐4,9‐dihydro‐3H‐pyrido[3,4‐b]indole and β‐Carboline Derivatives

Abstract A visible‐light‐induced trifluoromethylation of isonitrile‐substituted indole derivatives has been developed from the reaction of isonitrile‐substituted indoles with Togni II reagent, affording 1‐(trifluoromethyl)‐4,9‐dihydro‐3 H ‐pyrido[3,4‐b]indoles in moderate to good yields. The further transformations to β ‐carboline derivatives and a harmacine derivative have been performed, demonstrating the potential synthetic utility of this method. A preliminary biological study indicated that the CF 3 ‐containing harmine analogue significantly stimulated the secretion of glucagon‐like peptide‐1 (GLP‐1), suggesting an improvement in treating diabetes. magnified image