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An alkyne hydrosilylation-oxidation strategy for the selective installation of oxygen functionality.

ABSTRACT: Alkynes bearing propargylic, homopropargylic, and bishomopropargylic hydroxyl groups are shown to serve as precursors for ketone or alpha-hydroxy ketone functionality. The approach hinges on the intermediacy of vinylsilanes created through regioselective hydrosilylation catalyzed by the complex [Cp*Ru(MeCN)3]PF6. Several oxidative pathways of linear and cyclic vinylsilanes are studied, and the possibility of diastereoselective epoxidation of cyclic vinylsilanes is demonstrated. The sequences constitute the equivalent of stereoselective aldol, homo-aldol, and bishomo-aldol type processes. The method is applied to a short synthesis of the piperidine alkaloid, spectaline.

SUBMITTER: Trost BM

PROVIDER: S-EPMC2581901 | biostudies-literature | 2005 Jul

REPOSITORIES: biostudies-literature

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An alkyne hydrosilylation-oxidation strategy for the selective installation of oxygen functionality.

Trost Barry M BM Ball Zachary T ZT Laemmerhold Kai M KM

Journal of the American Chemical Society 20050701 28

Alkynes bearing propargylic, homopropargylic, and bishomopropargylic hydroxyl groups are shown to serve as precursors for ketone or alpha-hydroxy ketone functionality. The approach hinges on the intermediacy of vinylsilanes created through regioselective hydrosilylation catalyzed by the complex [Cp*Ru(MeCN)3]PF6. Several oxidative pathways of linear and cyclic vinylsilanes are studied, and the possibility of diastereoselective epoxidation of cyclic vinylsilanes is demonstrated. The sequences con ...[more]

PMID: 16011365

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