title: 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.
authors.affiliation: Department of Chemistry, University of Puerto Rico, Río Piedras Campus, PO Box 70377, San Juan, PR 00931-3346, USA.
authors.forename: Raúl R
authors.initials: RR
authors.lastname: Rodríguez-Berríos
authors.forename: Gerardo
authors.initials: G
authors.lastname: Torres
authors.forename: José A
authors.initials: JA
authors.lastname: Prieto