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Published on: May 26, 2019
Synergistic B/Cu-Catalyzed Asymmetric Propargylic Substitution of β-Hydroxyl Ketones
Kai Huang1, Zhihe Cen1, Hua Liang1
1Center for Supramolecular Chemistry and Catalysis and Department of Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China.
Abstract:
A copper/borinic acid catalytic platform was developed for the asymmetric propargylic substitution of β-hydroxy ketones with propargylic carbonates. This reaction involves nucleophilic activation of β-hydroxy ketones by borinic acid to form a cyclic boron enediolate, which then reacts with a Cu-allenylidene intermediate. A series of chiral β-alkynyl ketones were prepared with high diastereoselectivity and high enantioselectivity. The utility of this method was demonstrated by a millimole-scale reaction and downstream transformations.
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