Synthesis of several 3-substituted 2-trifluoromethylindoles via Mannich reaction of 2-trifluoromethylindoles

Several 2-trifluoromethyl derivatives of biologically active indoles, tryptamine, indole-3-acetic acid, oxypertine and tryptophan,were synthesized starting from 2-trifluoromethylindoles by use of the Mannich reaction and subsequent nucleophilic substitution reaction as key steps, In this study, chemoselective hydrolysis and reductions of the nitrile group to the respective carboxylic acid, amine and aldehyde in the presence of the trifluoromethyl group were achieved.