Studies on Tertiary Amine Oxides. XLVIII. The Reaction of Quinoline N-Oxide with Acrylonitrile

Abstract

Treatment of quinoline N-oxide (I) with acrylonitrile and acetic anhydride in hot dioxane or dimethylformamide resulted in the formation of β-(2-quinolyl) acrylonitrile (II) and di-(2-quinolyl) acetonitrile (III) in 34.4 and 3.3% yields, respectively. No definite product was obtained in the absence of acetic anhydride, whereas the reaction in excess acetic anhydride using no solvent caused the increase of the formation of III and conversely the decrease of that of II. In spite of such a markedly important role of acetic anhydride, it was further disclosed that, when a dioxane solution of I and acrylonitrile was heated in the presence of a catalytic amount of hydroquinone, II and β-(2-quinolyl)-lactonitrile (XI) were produced. The acrylonitrile derivative II should be assumed to result from the 1, 3-dipolar cycloaddition between the free I and acrylonitrile. The mechanism of formation of III was also discussed. Acrylamide and ethyl acrylate showed similar behaviors to that of acrylonitrile.