New compounds in ring‐opening reaction of 5‐substituted epoxyisoindolines

Abstract

Methoxy or nitro group present in the furan ring of tertiary alkenylfurfurylamine changes the expected results of both, the intramolecular [4+2]cycloaddition and the acid catalyzed ring-opening reaction of the derived oxatricycloadduct. With a 5-methoxy group, in addition to the expected 5-methoxyisoindoline 3, the corresponding hydroxy derivative 5 was obtained. On the other hand a 5-nitro group changes the outcome of the reaction even more profoundly. Instead of the expected 5-nitroisoindoline 12, 5-nitro-substituted epoxyisoindoline 6 submitted to ring-opening reaction with the mixture of hydrobromic and acetic acid, yielded the mixture of bromo-substituted epoxy compounds 7, 8, 9 and/or bromo-substituted isoindolines 10 and 11.