The imputed formation of 1,2,3-triazoles, triazines, and triazepines from hydrazinobenzoquinolines and nitrous acid. A correction

Abstract

It has been claimed that the reactions of 1-chloro-3-methylbenzo[f]quinoline (1), 4-chloro-2-methylbenzo[h]quinoline (7), 3-chloro-1-methylbenzo[f]quinoline (12), and 2-chloro-4-methylbenzo[h]quinoline (16) with hydrazine followed by nitrous acid give the 1,2,3-triazepine (3), the triazine (11), and the triazoles (15) and (19), respectively. These transformations are unprecedentated. The products are now correctly identified as, respectively, the pyrazolotriazine (5), the azide (9), and the tetrazoles (14) and (18); the reactions involved are unexceptional. The first product isolated from the chloro-compound (1) and hydrazine is not the hydrazine (2) but the aminonaphthylpyrazole (4). The pyrazolotriazine (5) formed from this with nitrous acid rearranges thermally to the pyrazolopyridazine (6).