Phenyl benzoate

Chemical properties

white crystalline powder

The Uses of Phenyl benzoate

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

Definition

ChEBI: A benzoate ester obtained by the formal condensation of phenol with benzoic acid.

Preparation

A 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%.

Synthesis Reference(s)

Canadian Journal of Chemistry, 61, p. 86, 1983 DOI: 10.1139/v83-015
Synthesis, p. 908, 1983 DOI: 10.1055/s-1983-30561
Tetrahedron Letters, 41, p. 1343, 2000 DOI: 10.1016/S0040-4039(99)02289-3

General Description

Phenyl 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.

Safety Profile

Moderately toxic by ingestion. When heated it emits acrid smoke and irritating fumes.

Purification Methods

Crystallise the ester from EtOH using ca twice the volume needed for complete dissolution at 69o. [Beilstein 9 IV 303.]