Kinetics and mechanism of 1-phenyl-5-methyltetrazole nitration in HNO3–H2SO4 system

Abstract

At nitration of 1-phenyl-5-methyltetrazole with nitric acid in aqueous solutions of sulfuric acid of 84–96% concentration a mixture forms of 1-(4-nitrophenyl)- and 1-(3-nitrophenyl)-5-methyltetrazoles in a ratio 60: 40. According to kinetic data, the tetrazole ring in the substrate is present in a protonated form. The protonation constants of 1-(4-carboxyphenyl)-5-methyltetrazole at the tetrazole ring and the carboxy group were determined. The Hammet’s electronic constant of the protonated tetrazole ring was calculated.