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Aerobic Pd-catalyzed sp3 C-H olefination: a route to both N-heterocyclic scaffolds and alkenes.

ABSTRACT: This communication describes a new method for the Pd/polyoxometalate-catalyzed aerobic olefination of unactivated sp(3) C-H bonds. Nitrogen heterocycles serve as directing groups, and air is used as the terminal oxidant. The products undergo reversible intramolecular Michael addition, which protects the monoalkenylated product from overfunctionalization. Hydrogenation of the Michael adducts provides access to bicyclic nitrogen-containing scaffolds that are prevalent in alkaloid natural products. Additionally, the cationic Michael adducts undergo facile elimination to release ?,?-unsaturated olefins, which can be further elaborated via C-C and C-heteroatom bond-forming reactions.

SUBMITTER: Stowers KJ

PROVIDER: S-EPMC3083468 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Aerobic Pd-catalyzed sp3 C-H olefination: a route to both N-heterocyclic scaffolds and alkenes.

Stowers Kara J KJ Fortner Kevin C KC Sanford Melanie S MS

Journal of the American Chemical Society 20110408 17

This communication describes a new method for the Pd/polyoxometalate-catalyzed aerobic olefination of unactivated sp(3) C-H bonds. Nitrogen heterocycles serve as directing groups, and air is used as the terminal oxidant. The products undergo reversible intramolecular Michael addition, which protects the monoalkenylated product from overfunctionalization. Hydrogenation of the Michael adducts provides access to bicyclic nitrogen-containing scaffolds that are prevalent in alkaloid natural products. ...[more]

PMID: 21476513

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