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Palladium-catalysed alkene chain-running isomerization.

ABSTRACT: We report a method for palladium-catalysed chain-running isomerization of terminal and internal alkenes. Using an air-stable 2,9-dimethylphenanthroline-palladium catalyst in combination with NaBAr4 promoter, olefins are converted to the most stable double bond isomer at -30 to 20 °C. Silyl enol ethers are readily formed from silylated allylic alcohols. Fluorinated substituents are compatible with the reaction conditions, allowing the synthesis of fluoroenolates. Catalyst loading as low as 0.05% can be employed on a gram scale.

SUBMITTER: Kocen AL

PROVIDER: S-EPMC5705238 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Palladium-catalysed alkene chain-running isomerization.

Kocen Andrew L AL Brookhart Maurice M Daugulis Olafs O

Chemical communications (Cambridge, England) 20170901 72

We report a method for palladium-catalysed chain-running isomerization of terminal and internal alkenes. Using an air-stable 2,9-dimethylphenanthroline-palladium catalyst in combination with NaBAr<sub>4</sub> promoter, olefins are converted to the most stable double bond isomer at -30 to 20 °C. Silyl enol ethers are readily formed from silylated allylic alcohols. Fluorinated substituents are compatible with the reaction conditions, allowing the synthesis of fluoroenolates. Catalyst loading as lo ...[more]

PMID: 28835962

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