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A syn outer-sphere oxidative addition: the reaction mechanism in Pd/Senphos-catalyzed carboboration of 1,3-enynes.

ABSTRACT: We report a combined experimental and computational study of Pd/Senphos-catalyzed carboboration of 1,3-enynes utilizing DFT calculations, ³¹P NMR study, kinetic study, Hammett analysis and Arrhenius/Eyring analysis. Our mechanistic study provides evidence against the conventional inner-sphere β-migratory insertion mechanism. Instead, a syn outer-sphere oxidative addition mechanism featuring a Pd-π-allyl intermediate followed by coordination-assisted rearrangements is consistent with all the experimental observations.

SUBMITTER: Wang Z

PROVIDER: S-EPMC9945512 | biostudies-literature | 2023 Feb

REPOSITORIES: biostudies-literature

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A syn outer-sphere oxidative addition: the reaction mechanism in Pd/Senphos-catalyzed carboboration of 1,3-enynes.

Wang Ziyong Z Lamine Walid W Miqueu Karinne K Liu Shih-Yuan SY

Chemical science 20230117 8

We report a combined experimental and computational study of Pd/Senphos-catalyzed carboboration of 1,3-enynes utilizing DFT calculations, 31P NMR study, kinetic study, Hammett analysis and Arrhenius/Eyring analysis. Our mechanistic study provides evidence against the conventional inner-sphere β-migratory insertion mechanism. Instead, a syn outer-sphere oxidative addition mechanism featuring a Pd-π-allyl intermediate followed by coordination-assisted rearrangements is consistent ...[more]

PMID: 36845936

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