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Palladium-catalyzed allylic cross-coupling reactions of primary and secondary homoallylic electrophiles.

ABSTRACT: The Pd(0)-catalyzed allylic cross-coupling of homoallylic tosylate substrates using boronic acids and pinacol esters is reported. The reaction uses 2-(4,5-dihydro-2-oxazolyl)quinoline (quinox) as a ligand and is performed at ambient temperature. The scope of the reaction is broad in terms of both the boronate transmetalating reagent and the substrate and includes secondary tosylates. Mechanistic studies support an alkene-mediated S(N)2-type stereoinvertive oxidative addition of unactivated primary and secondary alkyl tosylates.

SUBMITTER: Stokes BJ

PROVIDER: S-EPMC3412144 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Palladium-catalyzed allylic cross-coupling reactions of primary and secondary homoallylic electrophiles.

Stokes Benjamin J BJ Opra Susanne M SM Sigman Matthew S MS

Journal of the American Chemical Society 20120706 28

The Pd(0)-catalyzed allylic cross-coupling of homoallylic tosylate substrates using boronic acids and pinacol esters is reported. The reaction uses 2-(4,5-dihydro-2-oxazolyl)quinoline (quinox) as a ligand and is performed at ambient temperature. The scope of the reaction is broad in terms of both the boronate transmetalating reagent and the substrate and includes secondary tosylates. Mechanistic studies support an alkene-mediated S(N)2-type stereoinvertive oxidative addition of unactivated prima ...[more]

PMID: 22742056

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