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C(sp³ )-H Arylation Promoted by a Heterogeneous Palladium-N-Heterocyclic Carbene Complex in Batch and Continuous Flow.

ABSTRACT: A heterogeneous reusable palladium(II)-bis(N-heterocyclic carbene) catalyst was prepared and shown to catalyze the intramolecular C(sp³ )-H activation/cyclization of N-alkyl-2-bromoanilines furnishing indolines. This new catalytic system was based on a bis-imidazolium ligand immobilized on a spaced cross-linked polystyrene support. The iodide ligands on the catalyst played a central role in the efficiency of the process occurring through a "release and catch" mechanism. The heterogeneous nature of the catalyst was further exploited in the design of a continuous-flow protocol that allowed a more efficient recovery and reuse of the catalyst, as well as a very fast and safe procedure.

SUBMITTER: Ferlin F

PROVIDER: S-EPMC9303704 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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C(sp3 )-H Arylation Promoted by a Heterogeneous Palladium-N-Heterocyclic Carbene Complex in Batch and Continuous Flow.

Ferlin Francesco F Anastasiou Ioannis I Salameh Nihad N Miyakoshi Takeru T Baudoin Olivier O Vaccaro Luigi L

ChemSusChem 20220218 6

A heterogeneous reusable palladium(II)-bis(N-heterocyclic carbene) catalyst was prepared and shown to catalyze the intramolecular C(sp3 )-H activation/cyclization of N-alkyl-2-bromoanilines furnishing indolines. This new catalytic system was based on a bis-imidazolium ligand immobilized on a spaced cross-linked polystyrene support. The iodide ligands on the catalyst played a central role in the efficiency of the process occurring through a "release and catch" mechanism. The heterogene ...[more]

PMID: 35098689

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