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Stereoselective VO(acac)(2) Catalyzed Epoxidation of Acyclic Homoallylic Diols. Complementary Preparation of C2-syn-3,4-Epoxy Alcohols.

ABSTRACT: A substrate-controlled stereoselective epoxidation of free and monoprotected homoallylic diols was developed. This second-generation approach is based on the incorporation of a primary hydroxy directing group at the C2 methyl carbon, which changes the nature of the vanadium ester intermediate providing a new diastereoselectivity manifold for the preparation of 3,4-epoxy alcohols. This modification favored the formation of the challenging C2-syn epoxy alcohol product not previously available using the standard homoallylic alcohol substrates. These new epoxy alcohol diastereomers expand the scope and generality for the utilization of 3,4-epoxy alcohols as precursors for stereoselective polypropionate synthesis.

SUBMITTER: Rodriguez-Berrios RR

PROVIDER: S-EPMC3034253 | biostudies-literature | 2011 Feb

REPOSITORIES: biostudies-literature

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Stereoselective VO(acac)(2) Catalyzed Epoxidation of Acyclic Homoallylic Diols. Complementary Preparation of C2-syn-3,4-Epoxy Alcohols.

Rodríguez-Berríos Raúl R RR Torres Gerardo G Prieto José A JA

Tetrahedron 20110201 5

A substrate-controlled stereoselective epoxidation of free and monoprotected homoallylic diols was developed. This second-generation approach is based on the incorporation of a primary hydroxy directing group at the C2 methyl carbon, which changes the nature of the vanadium ester intermediate providing a new diastereoselectivity manifold for the preparation of 3,4-epoxy alcohols. This modification favored the formation of the challenging C2-syn epoxy alcohol product not previously available usin ...[more]

PMID: 21311601

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