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Enantioenriched dihydropyrones from beta-lactone templates.

G Greg Zipp·Mark A Hilfiker·Scott G Nelson
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Abstract

[reaction: see text] Optically active 4-substituted 2-oxetanones provide conduits for preparing 2,3-dihydro-4H-pyrone heterocycles. Enantioenriched beta-lactones are prepared by asymmetric catalytic acyl halide-aldehyde cyclocondensation reactions. Hydrazone anion-mediated beta-lactone ring opening and ensuing cyclization-dehydroamination of the derived beta-ketohydrazone afford the desired dihydropyrones (68-81%). Optimized lactone ring-opening-cyclization reaction conditions render a variety of optically active 4-substituted-2-oxetanones as effective precursors to enantioenriched 2,3-dihydro-4H-pyrones.

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CyclizationLactonesMolecular ConformationPyronesStereoisomerismTemplates, GeneticJournal ArticleResearch Support, Non-U.S. Gov't

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BibTeXRIS

G Greg Zipp, Mark A Hilfiker, Scott G Nelson. 2002-05-30. Enantioenriched dihydropyrones from beta-lactone templates.. https://doi.org/10.1021/ol025607u

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