Oxidation of steroidal 5-en-3β-ols with Jones reagent in ether

The two-phase oxidation of steroidal 5-en-3β-ol (via 5-en-3-ones) into corresponding 4-en-3,6-diones in diethyl ether with Jones reagent was investigated. It was found that the system Jones reagent/diethyl ether enables short reaction times and easy isolation of the obtained products. The exclusive abstraction of 4α-hydrogen during oxidation, together with molecular mechanics (MM2), and semiempirical (PM3) calculations, suggest that boat conformation of ring A precedes the formation of corresponding radicals (or cations). © 1994