Carbon Dioxide → Diphenyl carbonate

Participants

Reaction Conditions

Reaction Steps

There was added to a Parr stirred pressure reactor, 76.06 grams of phenol, 1.896 grams of diphenyl ether, 0.33 gram benzoquinone, 0.042 gram palladium diacetate, 0.035 gram of anhydrous cobalt diacetate, and 2.49 grams of tetrabutylammonium bromide. The reactor vessel was sealed, purged 4 times with CO2 at 400 psi and then charged with 0.278 mole of carbon dioxide, 0.209 mole of oxygen and 0.417 mole of carbon monoxide at room temperature. The resulting partial pressures of carbon dioxide were 400 psi, oxygen 300 psi, and carbon monoxide 600 psi. The mixture was heated to 100° C. while it was stirred rapidly to ensure efficient aeration of the solution phase. After 2 hours, 7.3 grams of diphenyl carbonate (8.4% yield based on phenol) had been produced. A total internal pressure drop of 195 psi was also observed during the first 2 hours. The reactor was exhausted to 1000 psi and then recharged with 300 psi of oxygen and 620 psi of carbon monoxide. An aliquot of the mixture was removed after 3 hours following the initiation of the reaction and it was found that 9.25 grams of diphenyl carbonate (10.7% yield) had formed based on GC. At the termination of the reaction which lasted 5 hours, a total of 13.2 grams of diphenyl carbonate (15.2% yield) had been formed. Recovery of the diphenyl carbonate is readily achieved by stripping the mixture to dryness at about 19 torr and 150°-190° C. followed by distillation at about 15 torr and 200° C.

Provenance & Evidence