Efficient Oxidative Cyclization of 1,6-Dienes: A Highly Diastereoselective Entry to Substituted Tetrahydropyrans

Authors


  • We thank the Deutsche Forschungsgemeinschaft (STA-634/1-1), the Fonds der Chemischen Industrie, and the Ernst-Schering-Stiftung (fellowship to S.R.) for financial support of this work. We are also grateful to Professor H.-U. Reissig for helpful discussions and generous support.

Abstract

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Widely applicable: Substituted tetrahydropyran products can be obtained in good to high yields and excellent diastereoselectivity by oxidative cyclization of 1,6-dienes (see scheme, PG=protecting group). In situ generated ruthenium tetroxide (1–5 mol %) serves as a catalyst and sodium periodate on wet silica serves as a terminal oxidant. The conversion of a cyclization product into a synthetically useful δ-lactone building block is also presented.

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