Catalytic Epoxidation of 3-Carene and Limonene with Aqueous Hydrogen Peroxide, and Selective Synthesis of α-Pinene Epoxide from Turpentine

Abstract

The epoxidation of turpentine (technical α-pinene), 3-carene, and limonene with aqueous hydrogen peroxide was studied in a new catalytic system employing manganese sulfate, salicylic acid, sodium bicarbonate, and acetonitrile, as a polar solvent. The proposed approach makes it possible to carry out a “chemical separation” of turpentine components, yielding valuable individual derivatives of monoterpenes without the need to isolate individual monoterpene reagents. Specific methods have been developed for the production of α-pinene epoxide, 3-carene epoxide, limonene diepoxide, as well as for two related compounds: 3-carene-5-one and 3-carene-2,5-dione.