Research Article

Rapid and Efficient Synthesis of Hydroxytriarylmethanes under Ultra Sonic Irradiation Using Keggin Heteropolyacids and Preyssler Catalysts in Green Conditions

Table 4

The reaction of o-cresol and 2-sulfobenzoeic anhydride in the presence of different catalyst at 140°C (time of reaction 60 min).

EntryCatalystYielda (%)

1H4SiW12O4065
2H3PW12O4068
3H14[NaP5W30O110]72
4H14[NaP5W30O110]/SiO235
5H2SO458
6ZnCl244

aIsolated yield.