Regioselective Synthesis of Polysubstituted N2-Alkyl/Aryl-1,2,3-Triazoles via 4-Bromo-5-iodo-1,2,3-triazole

The regioselective N2-substitution of 4-bromo-5-iodo-1,2,3-triazole with alkyl/aryl halides in the presence of K2CO3 in DMF produced the desired 2-substituted 4-bromo-5-iodo-1,2,3-triazoles as a major products in good to excellent regioselectivity. Subsequent chemoselective Suzuki-Miyaura cross-coupling reaction of N2-substituted 4-bromo-5-iodo-1,2,3-triazoles provided polysubstituted 1,2,3-triazoles efficiently.