Reaction of β-aminocinnamonitrile and its N-mono- and NN-di-substituted derivatives with benzonitrile oxides

Abstract

β-Aminocinnamonitrile (4a) reacts with benzonitrile oxides (2) to give, as primary products, the 3-aryl-5-(β-aminostyryl)-1,2,4-oxadiazoles (6) together with lesser a mounts of 3-aryl-4-cyano-5-phenylisoxazoles (3). In the case of p-nitrobenzonitrile oxide (2c), 3-(p-nitrophenyl)-5-phenyl-1,2,4-oxadiazole (7) is also obtained. The N-monosubstituted aminocinnamonitriles behave similarly, whereas the NN-disubstituted compounds yield only the 3-aryl-4-cyano-5-phenylisoxazoles (3). A mechanism is proposed.