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Designed construction of hydrogen-bonded host lattices with urea/thiourea, guanidinium and selected anions.

机译：设计了具有脲/硫脲，胍和选定阴离子的氢键主晶格的结构。

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摘要

This thesis reports a systematic investigation on the generation of new inclusion compounds by the combined use of urea/thiourea, guanidinium ion and various organic anions as building blocks of hydrogen-bonded host lattices and selected quaternary ammonium ion as the enclosed guests.;Various acids bearing specific functional groups have been explored as structure building components, including boric acid, Kemp's triacid, heterocyclic (thio)urea derivatives, aryl and N-heteroaryl carboxylic acids and (dithio)squaric acid. All the co-crystals and inclusion compounds built of molecular components in the afore-mentioned categories have been characterized by single-crystal X-ray analysis. As a result, the complexes exhibit a rich variety of inclusion topologies, such as networks containing isolated cages, open channels, intersecting tunnels, double-layer systems, and sandwich-like as well as wave-like layer structures.;Self-assembly of two-dimensional hydrogen-bonded honeycomb grids exhibiting the rosette motif has been conducted with the guanidinium cation and various anions as the building blocks, tetraalkylammonium ions of suitable bulk being employed as interlayer templates. It is noteworthy that the rosette layer constructed from three different trigonal-planar molecular components has been achieved. In addition, deviating from conventional topological design, the generation of new rosette layers, albeit highly distorted, has also been accomplished with 1,2-dithiosquarate and the dianionic form of 1,1'-biphenyl-2,2',6,6'-tetracarboxylate that do not conform to C3-symmetry. Although threefold molecular symmetry is regarded as a sacrosanct requirement for molecular building blocks in the construction of hydrogen-bonded rosette motif, this study shows that rosette motifs can be generated even if one of the building blocks does not have inherent threefold symmetry.;Study of compounds containing the deprotonated forms of Kemp's triacid (H3KTA) has revealed the chair or twist-boat conformation in six crystal structures. X-ray structural analysis showed that [C(NH2) 3+] · [C6H6(CH3) 3(COOH)2(COO-)] (2.2.2) exhibits a corrugated layer structure which mimics the rosette motif constructed from the guanidinium ion and the hydrogen carbonate dimer. The tricarboxylate form of Kemp's triacid KTA3- in 3[C(NH2) 3+] · [C6H6(CH3) 3(COO-)3] (2.2.4) registers a record number of eighteen acceptor hydrogen bonds involving the convergent N--H donor sites from nine guanidinium ions. The crystal structure of 3[(C2H5)4N+] · 20[C(NH 2)3+] · 11[C6H6(CH 3)3(COOH) (COO-)2] · [C6H6(CH3)3(COOH)2(COO -)]·17H2O (2.2.3) features a hydrogen-bonded aggregate with a centrosymmetric pseudo-octahedral arrangement of H2KTA- anions surrounding an inner core composed of eight guanidinium ions. The unusual twist-boat conformation of KTA3- is found in [(CH3)4N +] · 2[C(NH2)3+] · [C6H6(CH3)3(COO- )3] · 2H2O (2.2.6), which is stabilized by the co-existence of guanidinium and tetramethylammonium cations.;Systematic investigation on hydrogen-bonded supramolecular assembly using aromatic carboxylic acids bearing linear or bent skeletons with urea/guanidinium resulted in the formation of mainly R228 and R126 synthon motifs. In addition, isostructures were also constructed by varying the length of the linker between two carboxylate groups, as in naphthalene-2,6-dicarboxylate (2.3.2) and biphenyl dicarboxylate (2.3.3).;Investigation on a series of hydrogen-bonded networks constructed with N-heteroaryl acids is described in Section 3.4. In this section, we focused on the connection modes within the heteroaryl dimer. The study of co-crystals and inclusion compounds based on 2-thiobarbituric acid (TBA) or trithiocyanuric acid (TCA) indicated that the dimer of TBA is present in all three crystals in the forms of ribbon, tetramer or separated dimer. In the case of 5-nitrobarbiturate, its dimer occurs in two ammonium salts and in three of its four thiourea complexes, but is absent in all three urea complexes.
机译：本论文系统地研究了通过结合使用尿素/硫脲，胍盐离子和各种有机阴离子作为氢键主晶格的构建基团，并选择季铵离子作为封闭的客体来生成新的包合物的方法。已经探究了具有特定官能团的结构构建组分，包括硼酸，肯普氏三酸，杂环（硫代）脲衍生物，芳基和N-杂芳基羧酸和（二硫代）方酸。通过单晶X射线分析已经表征了上述类别中由分子成分构成的所有共晶体和包含化合物。结果，这些复合物表现出多种多样的包含拓扑结构，例如包含隔离的笼子，明渠，相交的隧道，双层系统以及三明治状以及波浪状层结构的网络。用胍鎓阳离子和各种阴离子作为结构单元，已经完成了呈现玫瑰花序图案的二维氢键结合的蜂窝状网格，采用适当体积的四烷基铵离子作为中间层模板。值得注意的是，已经实现了由三种不同的三角平面分子成分构成的玫瑰花结层。此外，与常规的拓扑设计不同，新的玫瑰花结层的生成尽管高度变形，但也已通过1,2-二硫代方酸和1,1'-联苯-2,2'，6,6的二价阴离子形式完成。不符合C3对称性的'-四羧酸盐。尽管三重分子对称性被认为是构建氢键玫瑰花饰基序对分子构件的神圣要求，但这项研究表明，即使其中一个构建基团不具有固有的三重对称性，也可以生成玫瑰花序基序。含有肯普氏三酸（H3KTA）去质子化形式的化合物揭示了六种晶体结构中的椅子或扭曲结构。 X射线结构分析表明[C（NH2）3+]·[C6H6（CH3）3（COOH）2（COO-）]（2.2.2）表现出波纹状的层结构，模仿了胍基构造的玫瑰花序图案。离子和碳酸氢二聚体。 Kemp's三酸KTA3-在3 [C（NH2）3+]·[C6H6（CH3）3（COO-）3]（2.2.4）中的三羧酸盐形式记录了十八个涉及会聚N-的氢键-H供体来自9个胍离子。 3 [（（C2H5）4N +]·20 [C（NH 2）3+]·11 [C6H6（CH 3）3（COOH）（COO-）2]·[C6H6（CH3）3（COOH） 2（COO-）]·17H2O（2.2.3）的特征是氢键结合的聚集体，其中心对称的H2KTA-阴离子伪八面体结构围绕由八个胍离子组成的内核。在[（CH3）4N +]·2 [C（NH2）3+]·[C6H6（CH3）3（COO-）3]·2H2O（2.2.6）中发现了KTA3-的不同寻常的扭摆构象。 ；通过胍和四甲基铵阳离子的共存而稳定。；对带有线性或弯曲骨架的芳香族羧酸与脲/胍的氢键键合超分子组装的系统研究导致形成主要的R228和R126合成子基序。此外，还可以通过改变两个羧酸酯基团之间的连接基长度来构建同构结构，例如在萘-2,6-二羧酸酯（2.3.2）和联苯二羧酸酯（2.3.3）中。由N-杂芳基酸构成的键合网络在第3.4节中进行了描述。在本节中，我们重点介绍杂芳基二聚体中的连接方式。对基于2-硫代巴比妥酸（TBA）或三硫氰尿酸（TCA）的共晶体和包合物的研究表明，TBA的二聚体以带状，四聚体或分离的二聚体形式存在于所有三个晶体中。就5-硝基巴比妥酸盐而言，其二聚体存在于两种铵盐和其四种硫脲复合物中的三种中，但在所有三种脲复合物中均不存在。

著录项

  • 作者

    Han, Jie.;

  • 作者单位

    The Chinese University of Hong Kong (Hong Kong).;

  • 授予单位 The Chinese University of Hong Kong (Hong Kong).;
  • 学科 Chemistry Physical.
  • 学位 Ph.D.
  • 年度 2009
  • 页码 231 p.
  • 总页数 231
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

  • 入库时间 2022-08-17 11:38:24

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