Synthesis and structure elucidation of 3‐methoxy‐1‐methyl‐1 H ‐1,2,4,‐triazol‐5‐amine and 5‐methoxy‐1‐methyl‐1 H‐ 1,2,4,‐triazol‐3‐amine

Previously it was shown that condensation of dimethyl N ‐cyanodithioimidocarbonate ( 1a ) with methylhydrazine gave predominantly 1‐methyl‐5‐methylthio‐1 H ‐,2,4‐triazol‐3‐amine ( 2 ), which was initially identified erroneously as the regioisomer l‐methyl‐3‐methylthio‐1 H ‐1,2,4‐triazol‐5‐amine ( 3 ). We have found that reaction of dimethyl N ‐cyanoimidocarbonate ( 1b ) with methyl hydrazine affords a high yield of 3‐methoxy‐1‐methyl‐1 H ‐1,2,4‐triazol‐5‐amine ( 4 ) rather than the regioisomer 5‐methoxy‐1‐methyl‐1 H‐ 1,2,4‐triazol‐3‐amine ( 5 ). The structure assignment of 4 was confirmed by X‐ray crystallographic analysis of the benzenesulfonyl isocyanate adduct 7 . Triazole 5 was obtained after reacting dimethyl N ‐cyanothioimidocarbonate ( 1c ) with methylhydrazine.