Total Syntheses

Reaction scheme for total synthesis of the natural product Hexacyclinic Acid (A,B,C-Rings)
Total synthesis of Hexacyclinic Acid (A,B,C-Rings):
Reference:Stellfeld, T.; Bhatt, U.; Kalesse, M. Org. Lett. 2004, 6, 3889. DOI
Reactions:O-H → O-SiMe2tBu • HWE → DienoateEster • Ozonolysis • EnoateEster → Allyl-OH • Allyl-OH → Enal • CarboxAmide(Evans) → CarboxAmide(Weinreb) • O-H → O-SiMe2tBu • Aldol-B-Evans • CarboxAmide enolate+Aldehyde (asym) • Diels-Alder, Intram, Yne • Cyclopentanone • Bicyclo(430) • Mg-Alkynyl+Aldehyde • Propargyl-OH → Ynone • CarboxAmide(Weinreb) → Aldehyde • Olefin cross metathesis • Cu-Vinyl+Enone • Mg-R → Cu-R • Ketone → Alkyl-OH • EnolSilane+EnoateEster • ConjAdd EnolSilane • Cyclobutane • Bicyclo(320) • O-H → O-SiPh2tBu • O-SiMe2tBu → O-H • CompE+-Si-O/Si-O+H2O • Alkyl-OH → Ketone •
Reagents:SiMe2tBu-Cl • O3; Me2S • P(O)(OR)2CH2-Vinyl • LiNiPr2 • AlHiBu2 • MnO2 • Chiral auxiliary (amide-Evans) • B(OTf)Bu2 • NMe(OMe)-AlMe2 • Alkynyl-MgX • Dess-Martin • SiMe2tBu-OTf • AlHiBu2 • Chiral auxiliary (amide-Evans) • Vinyl-MgX • CuBr·SMe2 • AlH4-Li+ • Grubbs-Hoveyda • Acrylate • SiPh2tBu-Cl • Sulfonic acid, Camphor • RuO4-Pr4N+, NMO • SiMe3-I • Fluoride, R4N+ •