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Catalytic asymmetric intermolecular stetter reaction of heterocyclic aldehydes with nitroalkenes: backbone fluorination improves selectivity.

ABSTRACT: The catalytic asymmetric intermolecular Stetter reaction of heterocyclic aldehydes and nitroalkenes has been developed. We have identified a strong stereoelectronic effect on catalyst structure when a fluorine substituent is placed in the backbone. X-ray structure analysis provides evidence that hyperconjugative effects are responsible for a change in conformation in the azolium precatalyst. This new N-heterocyclic carbene precursor bearing fluorine substitution in the backbone results in significantly improved enantioselectivities across a range of substrates.

SUBMITTER: DiRocco DA

PROVIDER: S-EPMC2747345 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Catalytic asymmetric intermolecular stetter reaction of heterocyclic aldehydes with nitroalkenes: backbone fluorination improves selectivity.

DiRocco Daniel A DA Oberg Kevin M KM Dalton Derek M DM Rovis Tomislav T

Journal of the American Chemical Society 20090801 31

The catalytic asymmetric intermolecular Stetter reaction of heterocyclic aldehydes and nitroalkenes has been developed. We have identified a strong stereoelectronic effect on catalyst structure when a fluorine substituent is placed in the backbone. X-ray structure analysis provides evidence that hyperconjugative effects are responsible for a change in conformation in the azolium precatalyst. This new N-heterocyclic carbene precursor bearing fluorine substitution in the backbone results in signif ...[more]

PMID: 19722669

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