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Scope and mechanism of the Pt-catalyzed enantioselective diboration of monosubstituted alkenes.

ABSTRACT: The Pt-catalyzed enantioselective diboration of terminal alkenes can be accomplished in an enantioselective fashion in the presence of chiral phosphonite ligands. Optimal procedures and the substrate scope of this transformation are fully investigated. Reaction progress kinetic analysis and kinetic isotope effects suggest that the stereodefining step in the catalytic cycle is olefin migratory insertion into a Pt-B bond. Density functional theory analysis, combined with other experimental data, suggests that the insertion reaction positions platinum at the internal carbon of the substrate. A stereochemical model for this reaction is advanced that is in line both with these features and with the crystal structure of a Pt-ligand complex.

SUBMITTER: Coombs JR

PROVIDER: S-EPMC3805123 | biostudies-literature | 2013 Jul

REPOSITORIES: biostudies-literature

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Scope and mechanism of the Pt-catalyzed enantioselective diboration of monosubstituted alkenes.

Coombs John R JR Haeffner Fredrik F Kliman Laura T LT Morken James P JP

Journal of the American Chemical Society 20130718 30

The Pt-catalyzed enantioselective diboration of terminal alkenes can be accomplished in an enantioselective fashion in the presence of chiral phosphonite ligands. Optimal procedures and the substrate scope of this transformation are fully investigated. Reaction progress kinetic analysis and kinetic isotope effects suggest that the stereodefining step in the catalytic cycle is olefin migratory insertion into a Pt-B bond. Density functional theory analysis, combined with other experimental data, s ...[more]

PMID: 23862690

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