title: Studies for the enantiocontrolled preparation of substituted tetrahydropyrans: Applications for the synthesis of leucascandrolide A macrolactone.
abstract: Strategies for the stereocontrolled preparations of 2,6-cis-and 2,6-trans-substituted tetrahydropyrans have been devised. These studies have explored methodology for asymmetric induction in SE' reactions using chiral 1,3,2-diazaborolidine controllers. Reactions with aldehydes at -78 °C yield nonracemic 1,5-diols for chemoselective internal backside displacements. This concept is developed as a flexible and reliable strategy in studies toward leucascandrolide A macrolactone2via the sequential applications of SE' reactions leading to the C1-C9aldehyde14, and thebis-tetrahydropyran59, respectively.
authors.affiliation: Department of Chemistry, Indiana University, Bloomington, IN 47405, United States.
authors.forename: David R
authors.initials: DR
authors.lastname: Williams
authors.forename: Scott V
authors.initials: SV
authors.lastname: Plummer
authors.forename: Samarjit
authors.initials: S
authors.lastname: Patnaik
keywords: Asymmetric induction; Boron-auxiliary; Nonracemic 1,5-diols; SE′ reactions; Tetrahydropyran synthesis