Pyridinium compounds. Part I. Carbon–nitrogen bond cleavage in p-nitrobenzylpyridinium ion and related α-substituted derivatives by aqueous sodium hydroxide

Abstract

Treatment of N-(p-nitrobenzyl)pyridinium benzenesulphonate with aqueous sodium hydroxide gives pp′-di-formylazoxybenzene (40%), C-(p-nitrophenyl)-N-benzaldehyde nitrone (30%) and p-nitrobenzaldehyde (7·5%). N-(1-p-Nitrophenylethyl)pyridinium benzenesulphonate and N-(p-nitrodiphenylmethyl)pyridinium benzenesulphonate react with aqueous sodium hydroxide to give pp′-diacetylazoxybenzene (75%) and p-nitrobenzophenone (40%) respectively. The nature of the substituents on the benzylic carbon affects the nature of the products.