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Updated: Jul 10, 2026

A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Solid phase synthesis of highly substituted tetrahydropyrans by tandem ene-reaction/intramolecular Sakurai
Sylvain Broussy1, Herbert Waldmann
1Max-Planck-Institut für molekulare Physiologie, Abteilung Chemische Biologie, Otto-Hahn-Strasse 11, 44227 Dortmund.
Abstract:
A solid-phase tandem ene-reaction/intramolecular Sakurai cyclization sequence has been developed to synthesize highly substituted tetrahydropyran derivatives in two steps from aldehydes and with complete control of the relative stereochemistry of the three newly formed stereocenters. The compounds are obtained with high purity after release from the solid support and can be easily isolated in multimilligram amounts. Moreover, we have shown that asymmetric induction is possible on solid phase and that enantiomerically pure tetrahydropyrans containing four stereocenters can be effectively synthesized with this method.
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