Stable heterocyclic primary nitroso-amines

Stable primary nitroso-amines are obtained by treating those heterocyclic amines which contain a CN system adjacent to the amino-group and no labile hydrogen atoms with nitrous acid. The presence of carbon, substituted nitrogen, oxygen, or sulphur atoms in the remaining portion of the heterocyclic ring does not militate against the formation of the nitroso-amines. The relationship between the structure of the primary nitrosoamino-system and imino, diazoate, and diazonium forms is discussed. Reactions of the nitroso-amines include ready reduction to hydrazines and a thermal arylation which involves a homolytic displacement of the nitroso-amino-group in a reaction similar to the Gomberg–Bachman process.