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Updated: Oct 16, 2025
Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Organocatalytic asymmetric formal oxidative coupling for the construction of all-aryl quaternary stereocenters
Zhiyang Li1,2, Yichen Li3, Xingguang Li1,4
1Department of Chemistry, The Hong Kong University of Science and Technology (HKUST) Clear Water Bay Kowloon Hong Kong SAR China sunjw@ust.hk.
Abstract:
A new catalytic asymmetric formal cross dehydrogenative coupling process for the construction of all-aryl quaternary stereocenters is disclosed, which provides access to rarely explored chiral tetraarylmethanes with excellent enantioselectivity. The suitable oxidation conditions and the hydrogen-bond-based organocatalysis have enabled efficient intermolecular C-C bond formation in an overwhelmingly crowded environment under mild conditions. para-Quinone methides bearing an ortho-directing group serve as the key intermediate. The precise loading of DDQ is critical to the high enantioselectivity. The chiral products have also been demonstrated as promising antiviral agents.
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