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Asymmetric, organocatalytic, three-step synthesis of alpha-hydroxy-(E)-beta,gamma-unsaturated esters.

ABSTRACT: An efficient and enantiocontrolled three-step synthesis of alpha-hydroxy-(E)-beta,gamma-unsaturated esters is reported. Enantioenriched alpha-selenyl aldehydes, prepared in one step by asymmetric, organocatalytic alpha-selenylation of aldehydes, were directly subjected to a Wittig reaction followed by allylic selenide to selenoxide oxidation and final spontaneous [2,3]-sigmatropic rearrangement to yield the target compounds in 43-65% overall yield and in 94-97% ee.

SUBMITTER: Hess LC

PROVIDER: S-EPMC2864524 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature

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Asymmetric, organocatalytic, three-step synthesis of alpha-hydroxy-(E)-beta,gamma-unsaturated esters.

Hess Lindsey C LC Posner Gary H GH

Organic letters 20100501 9

An efficient and enantiocontrolled three-step synthesis of alpha-hydroxy-(E)-beta,gamma-unsaturated esters is reported. Enantioenriched alpha-selenyl aldehydes, prepared in one step by asymmetric, organocatalytic alpha-selenylation of aldehydes, were directly subjected to a Wittig reaction followed by allylic selenide to selenoxide oxidation and final spontaneous [2,3]-sigmatropic rearrangement to yield the target compounds in 43-65% overall yield and in 94-97% ee. ...[more]

PMID: 20377201

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