diphenyl oxalate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:190.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution comprising 54.1% by weight of phenol, 45.3% by weight of dimethyl oxalate and 0.5% by weight of tetraphenoxytitanium was fed into the twelfth step from the top of a first fifty-plate Oldershaw-type reactive distillation column provided with a one liter bottom flask and having an inner diameter of 32 mm, at a flow rate of 600 ml/hr, and the bottom flask was heated by a mantle heater to a temperature of 190° C., while withdrawing a resultant vapor fraction from the top portion of the first column at a reflux ratio of 2 and condensing the withdrawn vapor fraction by a cooler, to transesterify dimethyl oxalate with phenol and to produce diphenyl oxalate. was fed into the twelfth step from the top of a first fifty-plate Oldershaw-type reactive distillation column provided with a one liter bottom flask while withdrawing a resultant vapor fraction from the top portion of the first column at a reflux ratio of 2 and condensing the withdrawn vapor fraction by a cooler

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: N,N'-diacetyloxamide (10 g, 0.058 mol), phenol (27.91 g, 0.297 mol) and sodium methoxide (0.2 g, 3.7 mmol) are charged into a three-necked flask equipped with a reflux condenser, a thermometer, an inlet tube for nitrogen, and a magnetic stirrer. The temperature is brought to 130° C., and after two hours the complete disappearance of the N,N'-diacetyloxamide is observed. The reaction mixture is then cooled and ethyl ether (30 ml) is added thereto. The compound of the title is separated from the reaction mixture by crystallization, recovered by filtration and recrystallized from absolute ethyl alcohol, yielding 4.5 g (18.6 mmol) of oxalic acid diphenyl ester with m.p. 132°-5° C. equipped with a reflux condenser is brought to 130° C. The reaction mixture is then cooled The compound of the title is separated from the reaction mixture by crystallization recovered by filtration recrystallized from absolute ethyl alcohol

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: N,N'-diacetyloxamide (10 g, 0.058 mol), phenol (27.91 g, 0.297 mol) and sodium methoxide (0.2 g, 3.7 mmol) are charged into a three-necked flask equipped with a reflux condenser, a thermometer, an inlet tube for nitrogen, and a magnetic stirrer. The temperature is brought to 130° C., and after two hours the complete disappearance of the N,N'-diacetyloxamide is observed. The reaction mixture is then cooled and ethyl ether (30 ml) is added thereto. The compound of the title is separated from the reaction mixture by crystallization, recovered by filtration and recrystallized from absolute ethyl alcohol, yielding 4.5 g (18.6 mmol) of oxalic acid diphenyl ester with m.p. 132°-5° C. equipped with a reflux condenser is brought to 130° C. The reaction mixture is then cooled The compound of the title is separated from the reaction mixture by crystallization recovered by filtration recrystallized from absolute ethyl alcohol

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Diphenyl oxalate was prepared from dimethyl oxalate and phenol by using the apparatus shown in FIG. 3 including first and second distillation reactors and a refining distillation column. second distillation reactors a refining distillation column

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In a 1,000 mL-volume three-necked flask, 27.3 g of diphenyl oxalate was dissolved in 600 mL of acetone. In the solution, an aqueous solution of 6.76 g of acetic acid and 7.77 g of potassium carbonate in 25 mL of water was dropwise added under stirring for 4 hours. The mixture was then stirred for 2 hours, and the produced precipitate was collected on a filter by suction. The collected precipitate was washed with acetone and dried under reduced pressure to give 19.9 g of potassium phenyl oxalate. These procedures were performed at room temperature. The mixture was then stirred for 2 hours the produced precipitate was collected on a filter by suction The collected precipitate was washed with acetone dried under reduced pressure

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In a 1,000 mL-volume three-necked flask, 27.3 g of diphenyl oxalate was dissolved in 600 mL of acetone. In the solution, an aqueous solution of 6.76 g of acetic acid and 7.77 g of potassium carbonate in 25 mL of water was dropwise added under stirring for 4 hours. The mixture was then stirred for 2 hours, and the produced precipitate was collected on a filter by suction. The collected precipitate was washed with acetone and dried under reduced pressure to give 19.9 g of potassium phenyl oxalate. These procedures were performed at room temperature. The mixture was then stirred for 2 hours the produced precipitate was collected on a filter by suction The collected precipitate was washed with acetone dried under reduced pressure

Conditions: temp:190.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution comprising 54.1% by weight of phenol, 45.3% by weight of dimethyl oxalate and 0.5% by weight of tetraphenoxytitanium was fed into the twelfth step from the top of a first fifty-plate Oldershaw-type reactive distillation column provided with a one liter bottom flask and having an inner diameter of 32 mm, at a flow rate of 600 ml/hr, and the bottom flask was heated by a mantle heater to a temperature of 190° C., while withdrawing a resultant vapor fraction from the top portion of the first column at a reflux ratio of 2 and condensing the withdrawn vapor fraction by a cooler, to transesterify dimethyl oxalate with phenol and to produce diphenyl oxalate. was fed into the twelfth step from the top of a first fifty-plate Oldershaw-type reactive distillation column provided with a one liter bottom flask while withdrawing a resultant vapor fraction from the top portion of the first column at a reflux ratio of 2 and condensing the withdrawn vapor fraction by a cooler

Conditions: temp:190.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution comprising 54.1% by weight of phenol, 45.3% by weight of dimethyl oxalate and 0.5% by weight of tetraphenoxytitanium was fed into the twelfth step from the top of a first fifty-plate Oldershaw-type reactive distillation column provided with a one liter bottom flask and having an inner diameter of 32 mm, at a flow rate of 600 ml/hr, and the bottom flask was heated by a mantle heater to a temperature of 190° C., while withdrawing a resultant vapor fraction from the top portion of the first column at a reflux ratio of 2 and condensing the withdrawn vapor fraction by a cooler, to transesterify dimethyl oxalate with phenol and to produce diphenyl oxalate. was fed into the twelfth step from the top of a first fifty-plate Oldershaw-type reactive distillation column provided with a one liter bottom flask while withdrawing a resultant vapor fraction from the top portion of the first column at a reflux ratio of 2 and condensing the withdrawn vapor fraction by a cooler

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 400 parts of an aqueous solution of sodium hydrogencarbonate having a pH of 8 were added to 200 parts of diphenyl carbonate, obtained through the decarbonylation reaction of diphenyl oxalate using tetraphenylphosphonium chloride as a catalyst, the mixture was heated to 90° C. and stirred for 1 hour. This washing step was repeated twice. To the obtained heavy solution (diphenyl carbonate layer) was further added 400 parts of distilled water, and the resulting mixture was heated to 90° C. and stirred for 1 hour. This additional washing step was repeated twice. The resulting heavy solution was purified by distillation in the same manner as in Example 3 at an yield of 85% to obtain diphenyl carbonate containing 0.09 ppm of hydrolyzable chlorine. 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.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 400 parts of an aqueous solution of sodium hydrogencarbonate having a pH of 8 were added to 200 parts of diphenyl carbonate, obtained through the decarbonylation reaction of diphenyl oxalate using tetraphenylphosphonium chloride as a catalyst, the mixture was heated to 90° C. and stirred for 1 hour. This washing step was repeated twice. To the obtained heavy solution (diphenyl carbonate layer) was further added 400 parts of distilled water, and the resulting mixture was heated to 90° C. and stirred for 1 hour. This additional washing step was repeated twice. The resulting heavy solution was purified by distillation in the same manner as in Example 3 at an yield of 85% to obtain diphenyl carbonate containing 0.05 ppm of hydrolyzable chlorine. 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.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 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 aluminum chloride as catalysts, the mixture was heated to 90° C. and stirred for 1 hour. This washing step was repeated twice to obtain diphenyl carbonate containing 7.9 ppm of hydrolyzable chlorine. 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.