Reactions of alkyl methyl ketoximes with tetrasulfur tetranitride antimony pentachloride complex (S4N42.SbCl5): A regioselective formation of 3-alkyl-4-methyl-1,2,5-thiadiazoles and their mechanism of formation

Article abstract of DOI:10.3987/COM-98-8258

Treatment of alkyl methyl ketoximes with tetrasulfur tetranitride antimony pentachloride complex (S₄N₄·SbCl₅) in aromatic solvents such as benzene and toluene at 60 °C led to the regioselective formation of 3-alkyl- 4-methyl-1,2,5-thiadiazoles in low yields, whereas the reactions of alkyl aryl ketoximes under the same conditions gave exclusively N-arylalkanamides in good yields. A mechanism is proposed for the formation of 3-alkyl-4- methyl-1,2,5-thiadiazoles.