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Alkenes from ?-lithiooxyphosphonium ylides generated by trapping ?-lithiated terminal epoxides with triphenylphosphine.

ABSTRACT: Terminal epoxides undergo lithium 2,2,6,6-tetramethylpiperidide-induced ?-lithiation and subsequent interception with Ph(3)P to provide a new and direct entry to ?-lithiooxyphosphonium ylides. The intermediacy of such an ylide is demonstrated by representative alkene-forming reactions with chloromethyl pivalate, benzaldehyde and CD(3)OD, giving a Z-allylic pivalate, a conjugated E-allylic alcohol and a partially deuterated terminal alkene, respectively, in modest yields.

SUBMITTER: Hodgson DM

PROVIDER: S-EPMC3511028 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Alkenes from β-lithiooxyphosphonium ylides generated by trapping α-lithiated terminal epoxides with triphenylphosphine.

Hodgson David M DM Persaud Rosanne S D RS

Beilstein journal of organic chemistry 20121107

Terminal epoxides undergo lithium 2,2,6,6-tetramethylpiperidide-induced α-lithiation and subsequent interception with Ph(3)P to provide a new and direct entry to β-lithiooxyphosphonium ylides. The intermediacy of such an ylide is demonstrated by representative alkene-forming reactions with chloromethyl pivalate, benzaldehyde and CD(3)OD, giving a Z-allylic pivalate, a conjugated E-allylic alcohol and a partially deuterated terminal alkene, respectively, in modest yields. ...[more]

PMID: 23209528

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