A theoretical study of the molecular mechanism and stereoselectivity of the epoxidation reaction of 4a,14a- dimethyl-5a-cholest-8-en-3-one using m-CPBA have been carried out at the B3LYP/6-31(d,p) level of theory. The calculation of activation and reaction energies indicated that the attack α side on the double bond of 4a,14a- dimethyl-5a-cholest-8-en-3-one was favored both kinetically and thermodynamically and was in agreement with the experimental data.
