N-Heterocyclic Carbene-Catalyzed Umpolung of β,γ-Unsaturated 1,2-Diketones.

Org Lett

State Key Laboratory of Structural Chemistry, Center for Excellence in Molecular Synthesis, Fujian Institute of Research on the Structure of Matter, University of Chinese Academy of Sciences, Fuzhou, 350100, China.

Published: January 2018

The umpolung of β,γ-unsaturated diketones through N-heterocyclic carbene catalysis is described, which allows access to a variety of highly functionalized bicyclic cyclohexene-β-lactones and 1,3,4-triaryl benzenes. An unprecedented reaction pattern involving the catalytic formation of nucleophilic O-acylated homoenolate intermediate is proposed. A diverse set of transformations on the product further showed the synthetic potential of this protocol.

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http://dx.doi.org/10.1021/acs.orglett.7b03358DOI Listing

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