Kieslich D, Christoffers J. Formation of δ-Lactones by Cyanide Catalyzed Rearrangement of α-Hydroxy-β-oxoesters.
Org Lett 2021;
23:953-957. [PMID:
33464092 DOI:
10.1021/acs.orglett.0c04157]
[Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
δ-Valerolactone derivatives are formed by cyanide-catalyzed ring-transformation of cyclic α-hydroxy-β-oxoesters. This unprecedented reaction defines a new synthetic methodology, and the products are obtained in up to quantitative yields. Several alkyl substitutions as well as different ester residues are tolerated. Furthermore, benzo- and heteroarene-annulated starting materials are converted without problems. As an additional benefit, the starting materials are straightforwardly accessed by cerium-catalyzed aerobic α-hydroxylation of readily available β-oxoesters.
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