Isotopic labelling studies of the deaminative fragmentation of N-nitrosohydroxylamines and related compounds by kinetics, millimetre-wave spectroscopy and 17O NMR spectroscopy

Abstract

Nitrous oxide enriched with ¹⁸ O has been identified by millimetre-wave spectroscopy from the acid-induced hydrolysis of N ¹ -(2-adamantyl)-N ² -[ ¹⁸ O]hydroxydiazen-1-ium N ¹ -oxide 2 which, along with ¹⁷ O NMR studies and an α-deuterium kinetic isotope effect of k _H /k _D = 0.98 (±0.02) for N-nitroso-N-(2-[2- ² H]adamantyl)-O-b enzylhydroxylamine 4, confirms (i) that nitrous oxide is liberated in these reactions, and (ii) that the fragmentations in these reactions are step-wise and not concerted.