Acid-catalysed, thermal, and photochemical reactions of N-Nitroso-5H-dibenz[b,f ]azepine

Abstract

The acid-catalysed, thermal, and photochemical reactions of N-nitroso-6H-dibenz[b,f]azepine (2) have been studied and two general reaction types delineated. The first involves ring contraction to give acridine (3), acridine-9-carboxaldehyde (5), and 9-methylacridine (4). The yields of these products are dependent on the reaction conditions, particularly the presence or absence of oxygen and the nature of the solvent. In the second type, the parent heterocyclic nucleus is retained, and 5H-dibenz[b,f]azepine (1) and 2-nitro-5H-dibenz[b,f]azepine (6) are the main products. These results are compared with those observed for (1), and some mechanistic details of the transformations are discussed.