Extractive reaction for epoxidation of cyclohexene to cyclohexene oxide using dioxiranes in the ketone/oxone system

Abstract

Extractive reaction for the epoxidation of cyclohexene to cyclohexene oxide using dioxirane was studied. The study was divided into 2 main parts: namely comparison of different preparation methods and effect of operating conditions such as stirring rate, type of solvent, initial solvent/aqueous ratio, temperature, pH and amount of catalyst on the performance of the system. The study showed that the best performance was obtained when cyclohexene was epoxidized with dioxirance in an extractive reaction system with the presence of the phase transfer catalyst. The extractive reaction process was found to be more efficient in term of cyclohexene oxide yield than the single-phase process because it bypassed the equilibrium limitation and prevented further reactions of the desired product. It was found that the rate of dioxirane formation increased with the presence of phase transfer catalyst. The yield of cyclohexene oxide increased with increasing stirringrate and amount of acetone. Dichloromethane was the best solvent for this system in this study. The optimum performance for the reaction time of 60 minutes was achieved when using the initial solvent/aqueous ratio of 0.83, temperature of 25 Cํ pH of 7.5 and stirring rate 2040 rpm. The maximum yield of 97.5% was obtained in this study.