Research Article
Rapid and Efficient Synthesis of Hydroxytriarylmethanes under Ultra Sonic Irradiation Using Keggin Heteropolyacids and Preyssler Catalysts in Green Conditions
Table 5
The reaction of o-cresol and 2-sulfobenzoeic anhydride in the presence of different catalysts at 55–65°C under ultrasonic irradiation (time of reaction 15 min).
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aIsolated yield. | ||||||||||||||||||||||||||||||