nanosilica extracted from rice husk in Polyhydroqinilion Synthesis

Abstract

Phosphosulfonic acid as a multi solid site was easily<br />prepared from the reaction of ammonium dihydrogen phosphate<br />with chlorosulfonic acid in CCl4and for improved its catalytic<br />activity was supported nano Silica was extracted from husk rice<br />contains about 95% of Silica the size of extracted nano silica was<br />determined by SEM efficiency of this solid acid in four component<br />condensation reaction of aromatic aldehydes, dimidone, diketon, an<br />ammonium acetate was investigated the results were clearly<br />shown that aldehydes having electron withdrawing and electron<br />donating groups were efficiently converted to the corresponding<br />Polyhydroqinilion the high yields and short time products were<br />produced at 110 0C under solvent free conditions