Diphenyl carbonate → Oxalic acid, diphenyl ester

Participants

Reaction Steps

400 parts of distilled water were added to 200 parts of diphenyl carbonate, obtained through the decarbonylation reaction of diphenyl oxalate using triphenyl phosphine and bromine (Br2) as catalysts, and the mixture was heated to 90° C. and stirred for 1 hour. This washing step was repeated twice. The obtained heavy solution (diphenyl carbonate layer) was purified by distillation in the same manner as in Example 3 at an yield of 85% to obtain diphenyl carbonate containing 0.7 ppm of hydrolyzable bromine. An ester interchange reaction between this diphenyl carbonate and bisphenol A was carried out in the same manner as in Example 1 except that a disodium salt of bisphenol A was used in place of sodium hydroxide as an ester interchange catalyst in an amount of 2.0×10−6 mole, in terms of sodium, based on bisphenol A, to synthesize polycarbonate. A pellet of this polycarbonate was used for the measurement of its physical properties. The conditions and results are shown in Tables III-A and III-B below.

Provenance & Evidence