Carboxylation of Cyclohexanone with Carbon Dioxide and Potassium Phenoxide. Dependence of the Reaction upon the Amount of Carbon Dioxide Complexed with Potassium Phenoxide

Abstract

The uptake of CO₂ by potassium phenoxide (PhOK) in N, N-dimethylformamide (DMF) was investigated in a vacuum system. Further, the carboxylation of cyclohexanone by various amounts of CO₂ complexed with PhOK was studied. The yield of the carboxylate at 30s increased with increase of M.R. (molar ratio of CO₂ absorbed by PhOK to PhOK initially added) in the range of M.R. less than 0.41. However, in the range of M.R. above 0.60, it decreased with increase of M.R. The time required for completion of the reaction depended on the M.R., and three ranges were distinguishable. The ultimate yield of the carboxylate in the carboxylation increase proportionally to M.R. value. It is considered that the source of CO₂ for carboxylate formation was CO₂ complexed with PhOK rather than uncomplexed CO₂.