The 12-tungstophosphoric acid supported on silica gel (PW/SiO2) exhibits excellent activity in the synthesis of 2,3-dihydroquinazolin-4(1H)-ones by cyclocondensation reaction of 2-aminobenzamide with carbonyl compounds in water under reflux conditions. The desired products have been obtained in short reaction times in high yields. Our method has been successfully applied for both aldehydes and ketones (aromatic and aliphatic). Easy recovery and reusable catalyst, easy work-up and avoidance of using harmful organic solvents are the major advantages of our method in comparison to existing methods.
