Studies with aza-heterocyclic N-oxides: Synthesis of some new aromatic N-oxide derivatives

Abstract

Benzofuroxan derivative (1a) reacts with the cyanoacetanilides (2a-d) to give the benzimidazole derivatives (3a-d). Benzofuroxan (1b) reacts with rhodanine derivatives (4a,b) in presence of sodium ethoxide to give the arylaminobenzoimidazole derivatives (6a,b); while the last reaction afforded the thiazolidinone derivatives (8a,b) and the o-benzoquinone dioxime derivatives (9a,b) when it was repeated in the presence of sodium acetate. Moreover, a series of quinoxalinyl 1,4-di-N-oxide derivatives were prepared starting from quinoxalin-1,4-di-N-oxide derivatives (10a-c). Plausible mechanisms to account for the formation of the products are discussed.