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[1,2]- and [1,4]-Wittig Rearrangements of ?-Alkoxysilanes: Effect of Substitutions at both the Migrating Benzylic Carbon and the Terminal sp2 Carbon of the Allyl Moiety.

ABSTRACT: Substituted ?-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 ?-alkoxysilanes show different reactivities with the syn diastereomer being the more reactive isomer.

SUBMITTER: Onyeozili EN

PROVIDER: S-EPMC3580876 | biostudies-literature | 2013 Jan

REPOSITORIES: biostudies-literature

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[1,2]- and [1,4]-Wittig Rearrangements of α-Alkoxysilanes: Effect of Substitutions at both the Migrating Benzylic Carbon and the Terminal sp2 Carbon of the Allyl Moiety.

Onyeozili Edith N EN Mori-Quiroz Luis M LM Maleczka Robert E RE

Tetrahedron 20130101 2

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 the syn diastereomer being the more react ...[more]

PMID: 23459008

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