A new strategy for the preparation of 11-oxygenated steroids synthesis of (±)-adrenosterone

Article abstract of DOI:10.1016/S0040-4039(98)01526-3

Conjugate 1,4-addition of 1-[(tert-butyldimethylsilyl)oxy]-2-methyl- 1,3-cyclohexadiene (5) to 2-methyl-cyclopentenone in highly polar media and subsequent alkylation of the resultant silyl enol ether (4) with phenylthiodienyl carbonate 10 in 5.0 M LiClO₄·Et₂O provides substrate 2. Exposure of 2 to TMSOTf/TMSOCH₂CH₂OTMS affords tetracyclic bis-ketal 3, which is converted into (±)-adrenosterone (1) in four steps.