Use of an aminosilyllithium for the diastereoselective synthesis of diphenyl oxasilacyclopentane acetals and polyols.
[reaction: see text] The conjugate addition reaction of a stable, in situ generated silyllithium gives a beta-hydroxysilyl ester with high diastereoselectivity. Conversion of the beta-hydroxysilyl ester to a beta-fluorosilyl ester affords the precursor to the oxasilacyclopentane acetal in high yields under mild conditions. A hydride reduction and subsequent intramolecular silylation lead to the acetal in excellent yields. Finally, highly selective nucleophilic substitution affords oxasilacyclopentanes, which undergo a mild oxidation to afford 1,3-trans diols with high selectivity.
Tenenbaum
Jason M
JM
Department of Chemistry, University of California, Irvine, California 92697-2025, USA.
Woerpel
K A
KA
D000080:Acetals / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D013237:Stereoisomerism
D000080:Acetals; D011108:Polymers; C024617:polyol