Araki Takahiro, Kondo Atsushi, Maeda Kazuyuki
Department of Applied Chemistry, Tokyo University of Agriculture and Technology, Koganei, Tokyo 184-8588 (Japan), Fax: (+81) 42-388-7040.
Chemistry. 2015 Apr 13;21(16):6257-64. doi: 10.1002/chem.201406518. Epub 2015 Mar 9.
Novel isomorphous pillared-layer-type crystalline lanthanide 1,3,5-benzenetriphosphonates were prepared with bpy and dbo as organic pillars (LnBP-bpy and LnBP-dbo; Ln: Ce, Pr, and Nd). Ab initio crystal structure solution using synchrotron X-ray powder diffraction data revealed that the organic pillars do not exist as neutral coordinating ligands but as cationic molecules. Especially the LnBP-dbo phases have ordered interlayer space filled with water molecules between the dbo pillars, and the interlayer water is successfully removed by heating under vacuum with slightly distorted but basically retained pillared layer structures. Microporosity of the materials is confirmed by adsorption of nitrogen, carbon dioxide, and hydrogen gases. Such microporous layered metal phosphonates pillared with cationic molecules should be unprecedented and should offer new strategies to design ordered microporous materials.
以联吡啶（bpy）和二苯并-18-冠-6（dbo）作为有机支柱，制备了新型同构柱状层状晶体镧系1,3,5-苯三膦酸盐（LnBP-bpy和LnBP-dbo；Ln：Ce、Pr和Nd）。利用同步辐射X射线粉末衍射数据进行的从头算晶体结构解析表明，有机支柱并非以中性配位配体形式存在，而是以阳离子分子形式存在。特别是LnBP-dbo相在dbo支柱之间具有填充水分子的有序层间空间，通过真空加热成功除去了层间水，同时支柱层结构略有扭曲但基本保留。通过氮气、二氧化碳和氢气的吸附证实了材料的微孔性。这种由阳离子分子支撑的微孔层状金属膦酸盐应该是前所未有的，并且应该为设计有序微孔材料提供新的策略。
