Total synthesis of 4-Androstene-3,17-dione:
| Reference: | Schmidt, R.; Huesmann, P. L.; Johnson, W. S. J. Am. Chem. Soc. 1980, 102, 5122. DOI |
| Reactions: | Claisen-Johnson • Li-Alkynyl+Alkyl-X • Li/H → Li-Alkynyl • Alkyl-X+Li-R • Wittig-alkyl → Ene-trans • Aldol-Na → Enone • Mg-Vinyl+Aldehyde • Ozonolysis • Na-Alkynyl+Alkyl-X • Alkyl-X+Na-R • Steroid synthesis • Cationic cyclization • Si-Propargyl+Carbenium • Cyclohexane • Cyclopentene • Bicyclo(440) • Bicyclo(430) • Mechanism • Alkyl-X → Alkyl-PRn • Li/H → Li-Furyl • Li-Aryl+Alkyl-X • Enal → Acetal • Alkyl-X → Alkyl-I • Acetal → Aldehyde • CarboxEster → Alkyl-OH • Alkyl-OH → Aldehyde • Ketal → Ketone • Aldol-Na → Enone • Cyclopentenone • Li-Me+Ketone • Enone+Li-R • Na/H → Na-Alkynyl • Wittig-Schlosser • |
| Reagents: | NaNH2 • SiMe3-CH2X • Propargyl-Si • HCl, H2O • Propenyl-MgX • Orthoacetate • AlH4-Li+ • Cr2O7·2PyH (PDC) • PPh3=CH-Alkyl • PhLi • HCl, H2O • Hydroxide, sodium • Me-Li • O3 • Hydroxide, sodium • Alkynyl-Li • Zn° • Acetic acid, trifluoro • BuLi(n) • TsOH • Glycol • Iodide, sodium • PPh3 • Furyl-Li • |