Epoxidation of β-pinene to 2,10-epoxypinane by Oxone

This paper describes a highly effective catalytic method for epoxidation of β-pinene to 2,10-epoxypinane using potassium peroxomonosulfate (Oxone) as oxidant and acetone as catalyst. Structure of 2,10-epoxypinane was characterized by data of infrared spectrum, GC-MS spectrum and 1H NMR spectrum. The procedure consists simply in stirring the substrate, NaHCO₃ and acetone, at 0°C, with dropwise addition of an aqueous solution of Oxone. Optimization of the conditions identified (1) the mole ratio of Oxone to β-pinene 0.8:1, (2) reaction temperature 40°C, (3) pH 7.0-7.5, and (4) reaction time 2.5h. The yield of 2,10-epoxypinane can reach 85.4% and the system exhibits good chemical selectivity and few byproducts.