Fidalgo-Marijuan Arkaitz, Amayuelas Eder, Barandika Gotzone, Larrea Edurne S, Bazán Begoña, Urtiaga Miren Karmele, Iglesias Marta, Arriortua María Isabel
Mineralogía y Petrología, Universidad del País Vasco (UPV/EHU), Barrio Sarriena s/n, Leioa, Bizkaia 48940, Spain.
BCMaterials, Basque Center for Materials, Applications and Nanostructures, Bld. Martina Casiano, 3rd Floor, UPV/EHU Science Park, Barrio Sarriena s/n, Leioa, Bizkaia 48940, Spain.
IUCrJ. 2018 Jul 20;5(Pt 5):559-568. doi: 10.1107/S2052252518007856. eCollection 2018 Sep 1.
Heterogeneous catalysts are of great interest in many industrial processes for environmental reasons and, during recent years, a great effort has been devoted to obtain metal-organic frameworks (MOFs) with improved catalytic behaviour. Few supramolecular metal-organic frameworks (SMOFs) are stable under ambient conditions and those with anchored catalysts exhibit favourable properties. However, this paper presents an innovative approach that consists of using metal nodes as both structural synthons and catalysts. Regarding the latter, metalloporphyrins are suitable candidates to play both roles simultaneously. In fact, there are a number of papers that report coordination compounds based on metalloporphyrins exhibiting these features. Thus, the aim of this bioinspired work was to obtain stable SMOFs (at room temperature) based on metallo-porphyrins and explore their catalytic activity. This work reports the environmentally friendly microwave-assisted synthesis and characterization of the compound [H(bipy)][(MnTPPS)(HO)]·2bipy·14HO (TPPS = -tetra-phenyl-porphine-4,4',4'',4'''-tetra-sulfonic acid and bipy = 4,4'-bi-pyridine). This compound is the first example of an MnTPPS-based SMOF, as far as we are aware, and has been structurally and thermally characterized through single-crystal X-ray diffraction, IR spectroscopy, thermogravimetry and transmission electron microscopy. Additionally, this work explores not only the catalytic activity of this compound but also of the compounds μ--[FeTCPP]·16DMF and [CoTPPS(bipy)(HO)]·6HO. The structural features of these supra-molecular materials, with accessible networks and high thermal stability, are responsible for their excellent behaviour as heterogeneous catalysts for different oxidation, condensation (aldol and Knoevenagel) and one-pot cascade reactions.
出于环境原因，多相催化剂在许多工业过程中备受关注。近年来，人们付出了巨大努力来获得具有改进催化性能的金属有机框架（MOF）。很少有超分子金属有机框架（SMOF）在环境条件下是稳定的，而那些带有锚定催化剂的SMOF表现出良好的性能。然而，本文提出了一种创新方法，即使用金属节点作为结构合成子和催化剂。关于后者，金属卟啉是同时扮演这两种角色的合适候选者。事实上，有许多论文报道了基于金属卟啉的配位化合物具有这些特征。因此，这项受生物启发的工作的目的是获得基于金属卟啉的稳定SMOF（在室温下）并探索其催化活性。这项工作报道了化合物[H(bipy)][(MnTPPS)(HO)]·2bipy·14HO（TPPS = -四苯基卟啉-4,4',4'',4'''-四磺酸，bipy = 4,4'-联吡啶）的环境友好型微波辅助合成及表征。据我们所知，该化合物是首个基于MnTPPS的SMOF实例，并通过单晶X射线衍射、红外光谱、热重分析和透射电子显微镜对其进行了结构和热性能表征。此外，这项工作不仅探索了该化合物的催化活性，还探索了化合物μ--[FeTCPP]·16DMF和[CoTPPS(bipy)(HO)]·6HO的催化活性。这些超分子材料的结构特征，具有可及的网络和高热稳定性，使其作为不同氧化、缩合（羟醛和Knoevenagel）及一锅法级联反应的多相催化剂表现出优异性能。
