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Abstract：
The design of metal-organic frameworks (MOFs) allows the definition of properties for their final application in small-scale heterogeneous catalysis. Incorporating various catalytic centers within a single structure can produce a synergistic effect, which is particularly intriguing for cross-coupling reactions. The URJC-1 material exhibits catalytic duality: the metal centers act as Lewis acid centers, while the nitrogen atoms of the organic ligand must behave as basic centers. The impact of reaction temperature, catalyst concentration, and basic agent concentration was evaluated. Several copper-based catalysts, including homogeneous and heterogeneous MOF catalysts with and without the presence of nitrogen atoms in the organic ligand, were assessed for their catalytic effect under optimal conditions. Among the catalysts tested, URJC-1 exhibited the highest catalytic activity, achieving complete conversion of 4-nitrobenzaldehyde with only 3% mol copper concentration in one hour. Furthermore, URJC-1 maintained its crystalline structure even after five reaction cycles, demonstrating remarkable stability in the reaction medium. The study also examined the impact of various substituents of the substrate alcohol on the reaction using URJC-1. The results showed that the reaction had high activity when activating substituents were present and for most cyclic alcohols rather than linear ones.
摘要：
金属有机骨架（MOF）的设计允许定义其在小规模多相催化中的最终应用的性质。在单一结构中结合各种催化中心可以产生协同效应，这是特别有趣的交叉偶联反应。URJC-1材料表现出催化二重性：金属中心充当路易斯酸中心，而有机配体的氮原子必须表现为基本中心。反应温度的影响,催化剂浓度,并对碱性试剂浓度进行评价。几种铜基催化剂，包括有机配体中存在和不存在氮原子的均相和非均相MOF催化剂，在最佳条件下评估了它们的催化效果。在测试的催化剂中，URJC-1表现出最高的催化活性，在1小时内仅用3%mol铜浓度实现4-硝基苯甲醛的完全转化。此外，URJC-1即使在五个反应循环后仍保持其晶体结构，在反应介质中表现出显著的稳定性。该研究还检查了底物醇的各种取代基对使用URJC-1的反应的影响。结果表明，当存在活化取代基时，对于大多数环状醇而不是直链醇，反应具有很高的活性。
