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Indolizinones as synthetic scaffolds: fundamental reactivity and the relay of stereochemical information.

ABSTRACT: Indolizinones are under-explored N-heterocycles that react with exquisite chemo- and stereoselectivity. An exploration of the fundamental reactivity of these azabicycles demonstrates the potential to relay stereochemical information from the ring-fusion to newly formed stereocenters on the bicyclic core. The indolizinone diene undergoes selective hydrogenation and readily participates in Diels-Alder cycloadditions as well as ene reactions. The vinylogous amide embedded in the five-membered ring is resistant to reaction when the diene is in place. However, removal of the diene allows for diastereoselective hydrogenation of, and 1,4-additions to, the vinylogous amide. These fundamental reactions with indolizinones have provided a structurally diverse array of products that hold promise in the context of natural product synthesis.

SUBMITTER: Hardin Narayan AR

PROVIDER: S-EPMC3342682 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

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Indolizinones as synthetic scaffolds: fundamental reactivity and the relay of stereochemical information.

Hardin Narayan Alison R AR Sarpong Richmond R

Organic & biomolecular chemistry 20111109 1

Indolizinones are under-explored N-heterocycles that react with exquisite chemo- and stereoselectivity. An exploration of the fundamental reactivity of these azabicycles demonstrates the potential to relay stereochemical information from the ring-fusion to newly formed stereocenters on the bicyclic core. The indolizinone diene undergoes selective hydrogenation and readily participates in Diels-Alder cycloadditions as well as ene reactions. The vinylogous amide embedded in the five-membered ring ...[more]

PMID: 22072189

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