Trifluoromethyl Sulfones and Perfluoroalkanesulfonamides of the Azole Series

Abstract

2-Phenyl-4-trifluoromethylsulfonylmethyl-2H-1,2,3-triazole was synthesized from 4-bromo-methyl-2-phenyl-2H-1,2,3-triazole and sodium trifluoromethanesulfinate CF₃SO₂Na. 1(2)-Ethyl-4-nitro-1(2)H-1,2,3-triazoles and 4-nitro-2-phenyl-2H-1,2,3-triazole were reduced to the corresponding amines. Intermediate 1,2-bis(1-ethyl-1H-1,2,3-triazol-4-yl)diazene 1-oxide exists as a mixture of syn and anti isomers, the former being stabilized via formation of a strong intramolecular hydrogen bond. The reduction of 2-ethyl-4-nitro-2H-1,2,3-triazole in the presence of HCl afforded the target 4-amino-2-ethyl-2H-1,2,3-triazole and also 4-amino-5-chloro-2-ethyl-2H-1,2,3-triazole. Treatment of alkyl-substituted 4-amino-1,2,3-triazoles with trifluoromethanesulfonyl chloride and pentafluoroethanesulfonyl chloride gave N-triazolyl-substituted trifluoromethane- and pentafluoroethanesulfonamides and -imides.