A Green Approach to Synthesize Dihydropyrimidinone Derivatives by Using Anhydrous ZnCl2 Catalyst Under Refluxing Condition in Heptane-Toluene Medium via Biginelli Reaction

摘要

Aldehydes, la-g (la, Ar = 4-Cl-C6H4, lb, Ar = 4-CH3-C6H4, lc, Ar = 2-Cl-C6H4, Id, Ar = 2-CH3-C6H4, le, Ar =-C6H5, Ar = 4-C1. CH,, lg, Ar = 2-C1-C6H4) reacted with acetylacetone 2a and urea/thiourea 3a-b in the presence of anhydrous zinc chloride under refluxing condition in heptane-toluene medium to give the corresponding 5-aceto-4-aryl-6-methyl-2-oxo-l,2,3,4-tetrahydropyridimidine 4a-d and 5-aceto-4-aryl-6-methyl-2-thio-l,2,3,4-tetrahydropyridimidine 4e-. The structure of the compounds 4a-g were confirmed by their UV, IR, ~1H NMR and ~(13)C NMR analysis.