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Pd^II -Catalyzed C(alkenyl)-H Activation Facilitated by a Transient Directing Group.

ABSTRACT: Palladium(II)-catalyzed C(alkenyl)-H alkenylation enabled by a transient directing group (TDG) strategy is described. The dual catalytic process takes advantage of reversible condensation between an alkenyl aldehyde substrate and an amino acid TDG to facilitate coordination of the metal catalyst and subsequent C(alkenyl)-H activation by a tailored carboxylate base. The resulting palladacycle then engages an acceptor alkene, furnishing a 1,3-diene with high regio- and E/Z-selectivity. The reaction enables the synthesis of enantioenriched atropoisomeric 2-aryl-substituted 1,3-dienes, which have seldom been examined in previous literature. Catalytically relevant alkenyl palladacycles were synthesized and characterized by X-ray crystallography, and the energy profiles of the C(alkenyl)-H activation step and the stereoinduction model were elucidated by density functional theory (DFT) calculations.

SUBMITTER: Liu M

PROVIDER: S-EPMC9320856 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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PdII -Catalyzed C(alkenyl)-H Activation Facilitated by a Transient Directing Group.

Liu Mingyu M Sun Juntao J Erbay Tuğçe G TG Ni Hui-Qi HQ Martín-Montero Raúl R Liu Peng P Engle Keary M KM

Angewandte Chemie (International ed. in English) 20220526 25

Palladium(II)-catalyzed C(alkenyl)-H alkenylation enabled by a transient directing group (TDG) strategy is described. The dual catalytic process takes advantage of reversible condensation between an alkenyl aldehyde substrate and an amino acid TDG to facilitate coordination of the metal catalyst and subsequent C(alkenyl)-H activation by a tailored carboxylate base. The resulting palladacycle then engages an acceptor alkene, furnishing a 1,3-diene with high regio- and E/Z-selectivity. The reactio ...[more]

PMID: 35467792

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