Taxol total synthesis

Preparation of a chiral ring a moiety via biomimetic cyclization and evaluation of a tandem nitrile oxide strategy for rings B/C

L. Alcaraz, J. J. Harnett, C. Mioskowski, T. Le Gall, Dong Soo Shin, J. R. Falck

Research output: Contribution to journalArticle

27 Citations (Scopus)

Abstract

A fully functionalized taxol ring A moiety 7 was efficiently prepared via biomimetic cation-olefin cyclization of chiral geraniol epoxide 2b using SnCl4 in toluene. Fractional crystallization provided endo-3 (50% yield from 2b) that was converted to aldehyde 5 by stereospecific epoxidation, secondary alcohol protection, and PCC oxidation. NaOMe-mediated ring opening secured enal 6. Addition of lithium dithiane to 6 at low temperature provided 7 as the sole product in good yield. A tandem nitrile oxide cycloaddition strategy for creating the remaining B/C carbocycles as well as key functionality present in both rings was validated, in part, by cyclization of 14 to tricyclic isoxazoline 15.

Original languageEnglish (US)
Pages (from-to)7209-7214
Number of pages6
JournalThe Journal of Organic Chemistry
Volume60
Issue number22
StatePublished - 1995

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Nitriles
Cyclization
Biomimetics
Paclitaxel
Oxides
Epoxidation
Cycloaddition
Epoxy Compounds
Toluene
Alkenes
Crystallization
Lithium
Aldehydes
Cations
Alcohols
Oxidation
Temperature
dithiane
geraniol
stannic chloride

ASJC Scopus subject areas

  • Organic Chemistry

Cite this

Taxol total synthesis : Preparation of a chiral ring a moiety via biomimetic cyclization and evaluation of a tandem nitrile oxide strategy for rings B/C. / Alcaraz, L.; Harnett, J. J.; Mioskowski, C.; Le Gall, T.; Shin, Dong Soo; Falck, J. R.

In: The Journal of Organic Chemistry, Vol. 60, No. 22, 1995, p. 7209-7214.

Research output: Contribution to journalArticle

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