手性三齿配体的合理设计：双功能钴（II）配合物/氢键用于对映选择性迈克尔加成反应。

Rational Design of Chiral Tridentate Ligands: Bifunctional Cobalt(II) Complex/Hydrogen Bond for Enantioselective Michael Reactions.

机构信息

NMPA 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.

State Key Laboratory of Southwestern Chinese Medicine Resources, School of Pharmacy, Chengdu University of Traditional Chinese Medicine, Chengdu 611137, China.

出版信息

Org Lett. 2022 Jun 3;24(21):3861-3866. doi: 10.1021/acs.orglett.2c01435. Epub 2022 May 23.

DOI:10.1021/acs.orglett.2c01435

PMID:35604128

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.

摘要

双功能手性三齿双（吡咯并[2,3-b] 吡唑啉）吡啶（PyBPI）配体已被设计、合成，并应用于不对称迈克尔加成反应中。使用 0.05 mol% 的 PyBPI-Co(II) 配合物，β,γ-不饱和α-酮酯与 4-羟基香豆素反应，以 93-99%的产率和 90-97%的对映选择性得到加成产物。实验和密度泛函理论（DFT）计算支持了双重活化方式，其中三齿配体与 Co(II)配位以活化酮酯，而 PyBPI 中的羟基和羰基通过两个不同的氢键与 4-羟基香豆素相互作用。