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An "aprotic" Tamao oxidation/syn-selective tautomerization reaction for the efficient synthesis of the C1-C9 fragment of fludelone.

ABSTRACT: An efficient synthesis of the C(1)-C(9) fragment of fludelone has been developed. The key step is a tandem silylformylation-crotylsilylation/Tamao oxidation sequence that establishes the C(5) ketone, the C(6), C(7), and C(8) stereocenters, and the C(9) alkene in a single operation from a readily accessed starting material. The stereochemical outcome at C(6) depends critically on the development of an "aprotic" Tamao oxidation, which leads to a reversal in the intrinsic diastereoselectivity observed using "standard" Tamao oxidation conditions.

SUBMITTER: Harrison TJ

PROVIDER: S-EPMC3466590 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature

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An "aprotic" Tamao oxidation/syn-selective tautomerization reaction for the efficient synthesis of the C1-C9 fragment of fludelone.

Harrison Tyler J TJ Rabbat Philippe M A PM Leighton James L JL

Organic letters 20120905 18

An efficient synthesis of the C(1)-C(9) fragment of fludelone has been developed. The key step is a tandem silylformylation-crotylsilylation/Tamao oxidation sequence that establishes the C(5) ketone, the C(6), C(7), and C(8) stereocenters, and the C(9) alkene in a single operation from a readily accessed starting material. The stereochemical outcome at C(6) depends critically on the development of an "aprotic" Tamao oxidation, which leads to a reversal in the intrinsic diastereoselectivity obser ...[more]

PMID: 22950417

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