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Phosphine-catalyzed ?'-umpolung addition of nucleophiles to activated ?-alkyl allenes.

ABSTRACT: Highly functionalized alkenes can be prepared through phosphine-catalyzed ?'-umpolung additions of nucleophiles (carbon-, oxygen-, nitrogen-, and sulfur-centered) to activated ?-disubstituted allenes, providing many potentially useful synthetic intermediates in good to excellent yields, often with high levels of stereoselectivity for the product olefin geometry. Various substitution patterns around the allene are compatible with the process, showcasing the synthetic utility of allenes under the conditions of nucleophilic phosphine catalysis.

SUBMITTER: Martin TJ

PROVIDER: S-EPMC3094471 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Phosphine-catalyzed β'-umpolung addition of nucleophiles to activated α-alkyl allenes.

Martin Tioga J TJ Vakhshori Venus G VG Tran Yang S YS Kwon Ohyun O

Organic letters 20110414 10

Highly functionalized alkenes can be prepared through phosphine-catalyzed β'-umpolung additions of nucleophiles (carbon-, oxygen-, nitrogen-, and sulfur-centered) to activated α-disubstituted allenes, providing many potentially useful synthetic intermediates in good to excellent yields, often with high levels of stereoselectivity for the product olefin geometry. Various substitution patterns around the allene are compatible with the process, showcasing the synthetic utility of allenes under the ...[more]

PMID: 21491870

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