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).
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aIsolated yield. |