Application of ¹³C and ¹⁵N spectroscopy to the study of electronic delocalization in NN bonds: Nitrosamines, hydrazones, triazenes and related protonated species

Abstract

Abstract 13 C and 15 N spectroscopies at natural abundance have been applied to the study of nitrogen lone‐pair delocalization in NN containing compounds: nitrosamines, nitramines, hydrazines, hydrazones and triazenes. Structure‐chemical shift correlations have been derived for nitrosamines; the 13 C upfield effect of a γ substituent has been used for assigning the configuration of both diastereoisomers in N , N ‐unsymmetrically substituted nitrosamines. Equations have been computed which permit the prediction of the electronic delocalization, expressed in terms of free enthalpy of activation ΔG , as a function of δ 15 N and of the length of the NN bond. 15 N spectroscopy has also been applied to the study of the protonated species of nitrosamines and of acceptor‐donor complexes of nitrosamines with Lewis acids. The behaviour of such NN containing compounds is compared to that of amides.