近日，南京大学谢劲及其小组的最新研究揭示了用于可见光能量转移催化的剪裁功能集成多核Au-Ag配合物。相关论文于2025年12月4日发表在《美国化学会杂志》上。

本研究通过整合光敏配体策略，合理设计并制备了一系列功能化的异核Au-Ag配合物。有趣的是，通过阴离子效应可以精确控制金属中心的数量，其中硝酸盐阴离子有利于Au-Ag-Au-Ag四核配合物的形成，而三氟甲烷磺酸盐有利于Au-Ag-Au三核配合物的产生。这种金属-金属相互作用的结构微调将增强分子刚性，从而延长三重态寿命。

值得注意的是，这些结构多样的Au-Ag配合物可以表现出广泛的配体到配体电荷转移（LLCT）吸收带，长三重态寿命和可调谐的发射特性，它们在可见光下可以作为高效的EnT光催化剂。它们可以在可见光照射下在温和的条件下实现不同种类烯烃的分子间[2 + 2]环加成。在不安装发色团官能团的情况下，可以成功地使用广泛的普通烯烃，提供丰富的结构多样的多取代环丁烷库，收率中等至良好（高达90%），具有一致的非对映选择性。密度泛函理论（DFT）的计算支持一种阶梯反应途径，其中第一个C-C键的形成决定了反应速率和立体选择性。

据介绍，作为贵金属的经典代表之一，金基光催化传统上依赖于单电子转移（SET）机制，由于可见光吸收差和激发态短，很少有系统能够参与三重态能量转移（EnT）催化。

附：英文原文

Title: Tailoring Function-Integrated Multinuclear Au–Ag Complex for Visible-Light Energy Transfer Catalysis

Author: Nan Zhang, Sitian Zhou, Shunruo Yao, Congqing Zhu, Weipeng Li, Jie Han, Jin Xie

Issue&Volume: December 4, 2025

Abstract: As one of the classical representatives of precious metals, gold-based photocatalysis has traditionally relied on single-electron transfer (SET) mechanisms, with few systems capable of engaging in triplet energy transfer (EnT) catalysis due to poor visible-light absorption and short-lived excited states. Herein, we rationally design and prepare a series of functionalized heteromultinuclear Au–Ag complexes by integrating a photosensitizing ligand strategy. It is interesting to find that the number of metal centers can be precisely controlled via the anion effect, where the nitrate anion benefits the formation of Au–Ag-Au-Ag tetranuclear complexes while trifluoromethanesulfonate facilitates the production of Au–Ag–Au trinuclear complexes. This structural fine-tunes over metal–metal interactions, would enhance molecular rigidity and consequently prolong triplet-state lifetimes. Remarkably, these structurally diverse Au–Ag complexes can exhibit broad ligand-to-ligand charge transfer (LLCT) absorption bands, long triplet lifetimes, and tunable emission properties, thus serving as efficient EnT photocatalyst under visible light. They can enable a robust intermolecular [2 + 2] cycloaddition of different kinds of alkenes under mild conditions by means of visible light irradiation. A wide range of general alkenes can be successfully employed without the installation of chromophore functional groups, affording a rich library of structurally diverse multisubstituted cyclobutanes in moderate to good yields (up to 90%) with consistent diastereoselectivity. Density functional theory (DFT) calculations support a stepwise EnT pathway in which the first C–C bond formation governs both the rate and stereoselectivity.

DOI: 10.1021/jacs.5c14788

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.5c14788