上海交通大学刘家旺小组探明了双功能光活性手性配体实现可见光诱导镍催化的对映选择性C−O偶联。2025年12月4日出版的《德国应用化学》杂志发表了这项成果。

在此，小组报道了通过将咔唑（Cz）基团结合到吡啶-恶唑啉（Pyox）支架上，设计和合成了一系列新的双功能光活性手性配体。这种二合一的设计不仅增强了配体的光收集能力，而且还实现了更有效的分子内通过键的电子/能量转移。利用这些配体，一个可见光驱动的，对映选择性的镍催化的C通过动力学分解（KR）过程，实现了杂二芳基与多种羧酸的O交叉偶联。该工艺在温和的条件下进行，具有广泛的底物范围和良好的官能团耐受性，以高产率和对映体选择性提供了广泛的阻转异构异联芳基酯和富对映体三氟甲磺酸酯。机理研究表明，在Pyox配体中加入Cz基团显著增强了可见光吸收，从而促进了高效的Ni(0)/Ni(II)/Ni(0)催化循环。

据了解，不对称金属光氧化还原催化（AMPC）通常依赖于光催化和手性金属催化循环之间不相容的双催化系统。目前基于双功能手性光活性催化剂的策略虽然很有前途，但通常是底物特异性和金属依赖性的。因此，合理设计新型双功能光活性手性催化剂，促进高效的对映选择转化仍然是一个重要而具有挑战性的目标。

附：英文原文

Title: Bifunctional Photoactive Chiral Ligands Enable Visible-Light-Induced Nickel-Catalyzed Enantioselective C−O Coupling

Author: Junjie Xue, Lei Su, Weiwei Fang, Shen Gao, Qingshu Zheng, Jiawang Liu

Issue&Volume: 2025-12-04

Abstract: Asymmetric metallaphotoredox catalysis (AMPC) typically relies on dual catalytic systems that often suffer from incompatibility between the photocatalytic and chiral metal catalytic cycles. Current strategies based on bifunctional chiral photoactive catalysts, while promising, are generally substrate-specific and metal-dependent. Therefore, the rational design of novel bifunctional photoactive chiral catalysts capable of promoting efficient enantioselective transformations remains an important yet challenging goal. Herein, we report the design and synthesis of a series of new bifunctional photoactive chiral ligands by incorporating carbazole (Cz) groups into a pyridine-oxazoline (Pyox) scaffold. This two-in-one design not only enhances the light-harvesting ability of the ligands but also enables more efficient intramolecular through-bond electron/energy transfer. Using these ligands, a visible-light-driven, enantioselective Ni-catalyzed CO cross-coupling of heterobiaryls with diverse carboxylic acids was realized via a kinetic resolution (KR) process. The protocol proceeds under mild conditions with broad substrate scope and excellent functional group tolerance, affording a wide range of atropisomeric heterobiaryl esters and enantioenriched triflates in high yields and enantioselectivities. Mechanistic studies reveal that the incorporation of Cz groups into the Pyox ligand significantly enhances visible-light absorption, thereby promoting an efficient Ni(0)/Ni(II)/Ni(0) catalytic cycle.

DOI: 10.1002/anie.202523823

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202523823