d-Xylonic acid: a solvent and an effective biocatalyst for a three-component reaction†
Abstract
A simple and effective synthesis of 3,4-dihydropyrimidin-2(1H)-ones/thiones and their derivatives from aldehydes, β-dicarbonyl compounds and urea or thiourea using D-xylonic acid both as a green solvent and an effective catalyst is described. Taking the environment and economy into account, the work presented here has the merits of environmental friendliness, easy operation, simple work-up, excellent yields and the avoidance of organic solvents and inexpensive catalysts. In addition, the good properties of D-xylonic acid have also been validated by the synthesis of 5-phenyl-1(4-methoxyphenyl)-3[(4-methoxyphenyl)-amino]-1H-pyrrol-2(5H)-one and 12-phenyl-9,9-dimethyl-8,9,10,12-tetrahydrobenzo[a]xanthen-11-one. The synthesized compounds were characterized by FT-IR, 1H NMR, 13C NMR and melting point.