Department of Applied Chemistry, Faculty of Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo, 169-8555, Japan.
Waseda Institute for Advanced Study, Waseda University, 1-6-1 Nishiwaseda, Shinjuku-ku, Tokyo, 169-8050, Japan.
Chemistry. 2018 Nov 16;24(64):17033-17038. doi: 10.1002/chem.201804441. Epub 2018 Nov 15.
Controlled assembly of siloxane-based building blocks provides a rational approach toward designed architectures of silica-based porous materials. Here, a non-hydrothermal method to prepare microporous crystals from cage-type oligosiloxanes is reported. The crystals formation occurs through an ordered assembly assisted by hydrogen bonds and subsequent intermolecular connection by silylation. Cage siloxanes with a double-four ring (D4R) structure were modified with dimethylsilanol groups. Intermolecular hydrogen bonding of the dimethylsilanol groups led to the formation of a pillared-layer structure consisting of D4R units. A new crystalline microporous material retaining the original ordered arrangement was realized by bridging adjacent cages within the crystals by direct silylation of the silanol groups with trichlorosilane. The use of this silylating agent created microporous crystals containing Si-H groups, proving the advantages of the proposed concept.
通过控制硅氧烷基砌块的组装，可以为设计二氧化硅基多孔材料的结构提供一种合理的方法。在这里，我们报道了一种非热液法，用于从笼型低聚硅氧烷制备微孔晶体。晶体的形成是通过氢键辅助的有序组装以及随后的硅烷化的分子间连接来实现的。用二甲基硅醇基团对具有双四元环（D4R）结构的笼型硅氧烷进行修饰。二甲基硅醇基团的分子间氢键导致形成由 D4R 单元组成的支柱层结构。通过用三氯硅烷直接硅烷化晶体中的相邻笼，实现了保留原始有序排列的新型结晶微孔材料。使用这种硅烷化剂可以制备含有 Si-H 基团的微孔晶体，这证明了所提出的概念的优势。
