Phenyl benzoate

UsesPhenyl Benzoate is a key reagent in the synthesis of soluble polyimides using dianhydride/diamine derivatives.

General DescriptionPhenyl benzoate is a phenyl ester of benzoic acid. Crystal structure of phenyl benzoate has been determined from 844 microdensitometer-measured intensities. All bond lengths and angles were reported to be normal. Phenyl benzoate undergoes Fries rearrangement catalyzed by heteropoly acids to yield the acylated phenols and esters.

PreparationA glass tube was charged with benzoic anhydride (1.13 g, 5.00 mmol), diphenyl carbonate (1.07 g, 5.00 mmol), and either Ti(OBu)4 (0.020 g, 0.059 mmol) or Sn(OMe)2Bu2 (0.017 g, 0.059 mmol) as catalyst. The reaction mixture was heated at 300 ℃ for 30 min. After cooling to room temperature, the crude product obtained was dissolved in dichloromethane (10 mL) and the solution was filtered. The solvent was evaporated and the product obtained after column chromatography (silica gel; CH2Cl2/cyclohexane, 4:1) was recrystallized from petroleum ether; yield 95%.