Title : Copper(I)-catalyzed synthesis of 1,2,3-Triazoles from azidoformates, electron-deficient azides
Since the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction was discovered, which is one of the classical click reactions, a various range of the 1,2,3-Triazole synthesis has been extensively developed. In case of formation of 1,2,3-triazole with electron-deficient azides such as N-sulfonyl , carbonyl, and cabamoyl, only a few system have been reported. We have first found the formation of regioselective 1,4-disubstituted 1,2,3-triazoles from terminal alkynes and azidoformates, which are electron-deficient azide groups, using commercialized [(CH3CN)4Cu]PF6 copper catalyst with mild condition. This methodology can be applied to the synthesis of various bioactive triazole derivatives with other electron-deficient groups.