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A borane-mediated palladium-catalyzed reductive allylic alkylation of α,β-unsaturated carbonyl compounds.

ABSTRACT: The development of the palladium-catalyzed allylic alkylation of in situ generated boron enolates via tandem 1,4-hydroboration is reported. Investigation of the reaction revealed insights into specific catalyst electronic features as well as a profound leaving group effect that proved crucial for achieving efficient allylic alkylation of ester enolates at room temperature and ultimately a highly preparatively useful synthesis of notoriously challenging acyclic all-carbon quaternary stereocenters. The method demonstrates boron enolates as viable pro-nucleophiles in transition-metal catalyzed allylic alkylation, potentially opening up further transformations outside their traditional use.

SUBMITTER: Trost BM

PROVIDER: S-EPMC8150111 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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A borane-mediated palladium-catalyzed reductive allylic alkylation of α,β-unsaturated carbonyl compounds.

Trost Barry M BM Zuo Zhijun Z Schultz Johnathan E JE Anugula Nagaraju N Carr Katherine A KA

Chemical science 20200113 8

The development of the palladium-catalyzed allylic alkylation of in situ generated boron enolates via tandem 1,4-hydroboration is reported. Investigation of the reaction revealed insights into specific catalyst electronic features as well as a profound leaving group effect that proved crucial for achieving efficient allylic alkylation of ester enolates at room temperature and ultimately a highly preparatively useful synthesis of notoriously challenging acyclic all-carbon quaternary ...[more]

PMID: 34123302

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