Kinetics of the addition of 5-aryltetrazoles to stable substituted benzonitrile oxides

Abstract

Stable arylnitrile oxides were able to react with 5-aryltetrazoles in the presence of a tertiary amine, giving open-chain addition products with the structure of 2,5-disubstituted tetrazoles. Kinetic measurements were performed at 35 °C, mostly in chloroform in the presence of triethylamine. Substituents on the tetrazole benzene ring had almost no effect, but for substitution on the nitrile oxide benzene ring a non-Hammett-like effect was found. Rates were higher in CHCl₃ than in (CHCl₃+ 10% MeOH), and with Et₂N than with PhMe₂N. The reaction mechanism is discussed.