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Published on: May 26, 2019
Enantioselective intermolecular all-carbon [4+2] annulation via N-heterocyclic carbene organocatalysis
Guoxiang Zhang1, Weici Xu, Jian Liu
1State Key Laboratory of Structural Chemistry, and Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Fujian Institute of Research on the Structure of Matter (FJIRSM), University of Chinese Academy of Sciences, Fuzhou 350100, China. xqfang@fjirsm.ac.cn.
Abstract:
The highly stereoselective intermolecular all-carbon [4+2] annulation between in situ generated acyclic dienolates and α,β-unsaturated acyl azoliums is disclosed. The identification of 2-acyloxy-3-butenones as suitable diene precursors is the key to the success of this transformation. The corresponding highly functionalized cyclohexene products, which are inaccessible from Diels-Alder reactions, were delivered with high levels of diastereo- and enantioselectivities. A series of further transformations based on the product showed the potential of this reaction.
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