1,2,4‐Triazoles. V . Nuclear magnetic resonance study of N ‐Methyl derivatives of 1,2,4‐triazoles

The chemical shifts of the N ‐methyl protons of a number of N ‐methylated‐1,2,4‐triazoles were studied. Substitution of methyl and methylthio groups in position 3 causes upfield shifts of the N ‐methyl signals, while substitution of α‐pyridyl, γ‐pyridyl, and phenyl groups causes downfield shifts. In 3,5‐disubstituted 1,2,4‐triazoles, substituents in positions 3 and 5 have additive effects on the chemical shifts of N ‐methyl groups, so that the chemical shifts of the N ‐methyl groups of such compounds can be calculated. In this way, it was possible to assign the peaks of mixtures of N ‐monomethylated derivatives obtained by methylation of 1,2,4‐triazoles.