Study of the Regioselectivity of the N-alkylation Reaction of 1H-1,2,4-Triazole with an O-tosyl Derivative, Using Two-Dimensional NMR Spectroscopy

The alkylation reaction of 1H-1,2,4-triazole with (4-methyl-2-phenyl-4,5-dihydrooxazol-4-yl)methyl-4-
methylbenzenesulfonate in presence of K2CO3 as base and a catalytic amount of tetrabutylammonium
bromide in N,N’-dimethylformamide, followed by an oxazoline ring-opening reaction in an acidic
medium, and protection of amine function, leads normally to obtain two regioisomers of N-protected β-
aminoalcohols with prevalence of the N1-isomer. After purification by column chromatography of the
crude reaction product, only a single product is obtained in 97% yield. Hence, there is need of its
identification by spectroscopic study.