Synthesis of 1,2,3-Triazoles via Huisgen 1,3-Dipolar Cycloaddition

Significance

Reported is a general synthetic route for 1,4-disubstituted 1,2,3-triazoles by a copper(II)-catalyzed Huisgen 1,3-dipolar cycloaddition of azides with a series of simple alkynes. In a one-pot conversion, compound 1 undergoes reaction with sodium azide affording trifluoroazido compound 2, which further participates in a Huisgen 1,3-dipolar cycloaddition with alkynes to yield 1,4-disubstituted 1,2,3-triazoles in high yields. Single regioisomeric triazoles are obtained, presumably owing to mechanistic differences between copper-catalyzed and normal thermal reactions (F. Himo et al. J. Am. Chem. Soc. 2005, 127, 210). Information on the preparation of starting material 1 is not provided.