Zheng Zhi-Wei, Zhou Jun-Jie, Liu Hua, Zhang Xiang-Yu, Zhao Jian, Zheng Da-Sheng, Huang Kun, Qin Da-Bin
Key Laboratory of Chemical Synthesis and Pollution Control of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong 637002, China.
Frontiers Science Center for New Organic Matter, Key Laboratory of Advanced Energy Materials Chemistry (MOE), College of Chemistry, Nankai University, Tianjin 300071, China.
Inorg Chem. 2024 Sep 9;63(36):16878-16887. doi: 10.1021/acs.inorgchem.4c02730. Epub 2024 Aug 27.
Effective CO transformations hold essential significance for carbon neutrality and sustainable energy development. Carboxylative cyclization of propargylic amines with CO serves as an atom-economic reaction to afford oxazolidinones, showing broad applications in organic synthesis and pharmaceutical fields. However, most catalysts involved noble metals, exhibited low efficiency, or required large amounts of base. Hence, it is imperative to explore alternative noble-metal-free catalysts in order to achieve efficient conversion while minimizing the use of additives. Herein, a novel nanopore-based Cu(II)-organic framework () based on a new imidazole carboxylic ligand was successfully constructed and exhibited excellent stability. Catalytic investigations revealed that the combination of with 1,4-diaza[2.2.2]bicyclooctane (DABCO) efficiently catalyzed the carboxylative cyclization of propargylic amines with CO, achieving turnover numbers of 142 based on the catalyst and 7.1 based on DABCO. as a heterogeneous catalyst maintained high catalytic performance even after being reused at least 5 cycles, with its structure remaining stable. The strong activation of Cu(II) cluster nodes of catalyst toward -NH- groups within organic substrates, as demonstrated by mechanism experiments, along with excellent CO adsorption performance and the presence of regular 1D channels, synergistically facilitates the reaction rate. This research presents the first instance of a Cu(II)-organic framework achieving this cyclization reaction, offering wide prospects for novel catalyst design and CO utilization.
高效的CO转化对于碳中和和可持续能源发展具有至关重要的意义。炔丙胺与CO的羧基环化反应作为一种原子经济反应，可生成恶唑烷酮，在有机合成和制药领域具有广泛应用。然而，大多数催化剂涉及贵金属，效率较低，或需要大量碱。因此，必须探索替代的无贵金属催化剂，以实现高效转化，同时尽量减少添加剂的使用。在此，基于一种新型咪唑羧酸配体成功构建了一种新型的基于纳米孔的Cu(II)有机框架（），并表现出优异的稳定性。催化研究表明，与1,4-二氮杂[2.2.2]双环辛烷（DABCO）的组合能有效催化炔丙胺与CO的羧基环化反应，基于催化剂的周转数为142，基于DABCO的周转数为7.1。作为一种多相催化剂，即使在至少重复使用5次后仍保持高催化性能，其结构保持稳定。机理实验表明，催化剂的Cu(II)簇节点对有机底物中的-NH-基团具有强烈的活化作用，同时具有优异的CO吸附性能和规则的一维通道，协同促进了反应速率。本研究首次报道了一种Cu(II)有机框架实现这种环化反应，为新型催化剂设计和CO利用提供了广阔前景。
