Aminolysis and hydrolysis of chromonyl oxazolones and some condensation reactions of 2-methylchromone leading to novel chromones

Abstract

The aminolysis of 4-[(4-oxo-4H-1-benzopyran-3-yl)methylene]-2-phenyl-1,3-oxazol-5(4H)-one with diethylamine gave N-[1-(diethylamino)-1-oxo-3-(4-oxo-4H-1-benzopyran-3-yl)prop-2-en-2-yl] benzamide. The hydrolysis of 2-methyl-4-[(4-oxo-4H-1-benzopyran-3-yl)methylene]-1,3-oxazol-5(4H)-one gave the α-keto-acid, which could be converted into amino-acid derivatives. Condensation of 2-methylchromone with diethyl oxalate, 2-formyl-NN-diethylbenzamide, and 2-formylbenzoic acid gave the α-keto-acid, (E)-NN-diethyl-2-[2-(4-oxo-4H-1-benzopyran-2-yl) vinyl]benzamide, and (E)-2-[(4-oxo-4H-1-benzopyran-2-yl) vinyl]benzoic acid, respectively.