Catalytic Rearrangement of a Tetrasubstituted Tetrahydropyridine

A new compound, 5-acetyl-2-amino-4-(2-chloro-5-nitrophenyl)-6-oxo-1-phenyl-1,4,5,6-tetrahydropyridine-3-carbonitrile, was synthesized by the reaction of 2-chloro-5-(nitrobenzylidene)malononitrile with malononitrile and aniline. The product was then subjected to catalytic rearrangement in the presence of ethylenediamine to obtain one more new compound, 4-(2-chloro-5-nitrophenyl)-6-oxo-2-(phenylamino)-1,4,5,6-tetrahydropyridine-3-carbonitrile. The structure of the products was confirmed by NMR spectroscopy and X-ray diffraction analysis. A plausible mechanism of the rearrangement reaction was proposed.