title: [1,2]- and [1,4]-Wittig Rearrangements of α-Alkoxysilanes: Effect of Substitutions at both the Migrating Benzylic Carbon and the Terminal sp2Carbon of the Allyl Moiety.
abstract: Substituted α-alkoxysilanes can be deprotonated by alkyllithium bases and made to undergo Wittig rearrangements to afford the #x0005B;1,4]- and [1,2]-rearranged products in varying ratios. Substitution at the benzylic migrating carbon and/or at the allylic carbon of the allyl moiety impacts the rearrangement reaction, influencing the reactivity as well as the [1,4]-/[1,2]-selectivity. Diastereomeric α-alkoxysilanes show different reactivities with thesyndiastereomer being the more reactive isomer.
authors: Department of Chemistry, Florida A&M University, Tallahassee, FL 32307 USA.
authors: Edith N
authors: EN
authors: Onyeozili
authors: Luis M
authors: LM
authors: Mori-Quiroz
authors: Robert E
authors: RE
authors: Maleczka
keywords: 1,2-shift; 1,4-shift; Wittig rearrangement; acylsilanes; alkoxysilanes