Novel synthesis of 1,4,5-trisubstituted 1,2,3-triazoles via a one-pot three-component reaction of boronic acids, azide, and active methylene ketones

A series of 1-aryl-5-trifluoromethyl (or difluoromethyl)-1,4,5-trisubstituted 1,2,3-triazoles were synthesized in high yield by a novel one-pot three-component reaction of arylboronic acids, sodium azide, and active methylene ketones, such as ethyl 4,4-difluoroacetoacetate or ethyl 4,4,4-trifluoroacetoacetate in the presence of Cu(OAc)2 and piperidine using a DMSO/H2O (10/1) mixture as solvent.