An efficient method for the synthesis of 4,6-diarylpyrimidin-2(1H)-ones or thiones by using SiO2.CAA. The condensation of acetophenone , aldehydes and Urea or thiourea in the presence of silica supported catalyst was employed to synthesize a variety of pyrimidinones or thiones in excellent yields. The remarkable feature of this synthic pathway are simple workup, shorter reaction times, high yields.