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Selective syntheses of ?(?,?) and ?(?,?) butenolides from allylic cyclopropenecarboxylates via tandem ring expansion/[3,3]-sigmatropic rearrangements.

ABSTRACT: Allylic cyclopropenecarboxylates undergo ring expansion reactions to give 2-allyloxyfuran intermediates, which subsequently rearrange to ?(?,?) butenolides via a Claisen rearrangement or to the corresponding ?(?,?) butenolides via further Cope rearrangement. Also described are methods for chirality transfer in the rearrangement of nonracemic allylic esters.

SUBMITTER: Xie X

PROVIDER: S-EPMC3908874 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature

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Selective syntheses of Δ(α,β) and Δ(β,γ) butenolides from allylic cyclopropenecarboxylates via tandem ring expansion/[3,3]-sigmatropic rearrangements.

Xie Xiaocong X Li Yi Y Fox Joseph M JM

Organic letters 20130320 7

Allylic cyclopropenecarboxylates undergo ring expansion reactions to give 2-allyloxyfuran intermediates, which subsequently rearrange to Δ(β,γ) butenolides via a Claisen rearrangement or to the corresponding Δ(α,β) butenolides via further Cope rearrangement. Also described are methods for chirality transfer in the rearrangement of nonracemic allylic esters. ...[more]

PMID: 23514430

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