Copper-mediated [3 + 2] cycloaddition of trifluoroacetimidoyl chlorides and N-isocyanoiminotriphenylphosphorane for the synthesis of 3-trifluoromethyl-1,2,4-triazoles

Herein, a facile and straightforward route to synthesize 3-trifluoromethyl-1,2,4-triazoles via copper-mediated [3 + 2] cycloaddition of trifluoroacetimidoyl chlorides and N-isocyanoiminotriphenylphosphorane (NIITP) has been described. Mo(CO)6 is utilized as an effective promotor to activate NIITP. The transformation features readily accessible reagents, mild reaction conditions, a broad substrate scope and high efficiency, and could be reproducible on a 3 mmol scale.