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Updated: Sep 22, 2025
Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
Rational Design of Chiral Tridentate Ligands: Bifunctional Cobalt(II) Complex/Hydrogen Bond for Enantioselective
Xiao-Bing Wang1, Yin Tian2, Li Zhou1
1NMPA Key Laboratory for Research and Evaluation of Innovative Drug, Key Laboratory of Green Chemical Media and Reactions, Ministry of Education, Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals, School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China.
Abstract:
Bifunctional chiral tridentate bis(pyrroloimidazolone)pyridine (PyBPI) ligands have been designed, synthesized, and applied in an asymmetric Michael addition. With a 0.05 mol % PyBPI-Co(II) complex, β,γ-unsaturated α-keto esters reacted with 4-hydroxycoumarin to give the adducts in 93-99% yields and 90-97% ee. Experiments and DFT calculations supported the dual activation manner, in which the tridentate ligand coordinated with Co(II) to activate the keto ester, and the hydroxyl and carbonyl groups in PyBPI interacted with 4-hydroxycoumarin via two different H bonds.
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