N-Hydroxyphthalimide catalyzed allylic oxidation of steroids with t-butyl hydroperoxide

Article abstract of DOI:10.1016/j.steroids.2014.12.004

A new and optimized procedure for the allylic oxidation of Δ⁵-steroids with t-butyl hydroperoxide in the presence of catalytic amounts of N-hydroxyphthalimide (NHPI) under mild conditions was developed, showing excellent regioselectivity and chemoselectivity (functional group compatibility). It was found that Co(OAc)₂ could enhance the catalytic ability of NHPI resulting in better yields and shorter reaction times. The reaction mechanism and the scope of the reaction with a variety of Δ⁵-steroidal substrates were also investigated.