A quick access to CF 3 -containing functionalized benzofuranyl, benzothiophene and indolyl heterocycles under catalyst-free conditions.

A catalyst-free one-pot synthetic protocol is presented for the preparation of CF 3 -containing benzofuran, indolin, and benzothiophene derivatives using readily available aromatic aldehydes and ketones. 2-Bromo-3,3,3-trifluoropropene was employed as a non-corrosive and environmentally benign trifluoromethylacetylene synthon for incorporation of the CF 3 group. The reaction proceeds via the formation of a suitably substituted 4,4,4-trifluoro-1-phenylbut-2-yn-1-ol intermediate, which undergoes 5- exo-dig cyclization, resulting in an exocyclic double bond with Z -configuration. The synthetic utility, substrate scope, tolerance to broader substrates are also presented.