N-nitroso compounds. Part 5. Hydrogen–deuterium exchange of N-nitroso-2-(alkyl or arylamino)acetonitriles in aqueous solution

Abstract

The hydrogen–deuterium exchange of the cyanomethyl protons of a series of nitrosamines, RN(NO)CH₂CN (R = alkyl, benzyl, p-substituted phenyl, and cyanomethyl), has been investigated kinetically in CD₃COCD₃–D₂O or CD₃CN–deuteriated phosphate buffer at 35.1 °C. The order of the ring substituents of the arylnitrosamines is found to be p-MeO > H > p-Cl. The electronic effect of the R group on the relative stability of the nitrosamino carbanion is discussed in relation to the resonance structure of the nitrosamines in aqueous solution.