On treatment with diphenyldichloromethane or anisal chloride in the presence of acetone and aqueous sodium hydroxide, pyridine undergoes condensation and ring cleavage to yield the enamine Schiff bases 1, 1-diphenyl-2-azadeca-1, 3Z, 5Z, 7E-tetraen-9-one (1) and 1-(4-methoxyphenyl)-2-azadeca-1E, 3Z, 5Z, 7E-tetraen-9-one (7). The reaction proceeds through attack of acetonyl carbanion on the initially formed bis-pyridinium salt, followed by ...
