Nanocavities with Fine Adjustment in Channel-Type Inclusion Crystals of Alkylammonium Deoxycholates. Control of Molecular Cavities by Partial Filling of Molecular Channels
Nanocavities with Fine Adjustment in Channel-Type Inclusion Crystals of Alkylammonium Deoxycholates. Control of Molecular Cavities by Partial Filling of Molecular Channels
复制标题
脱氧胆酸烷基铵通道型夹杂物晶体中具有微调的纳米腔。
DOI：
10.1021/ja982057f
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发表时间：
1998
影响因子：
15
通讯作者：
M. Miyata
中科院分区：
文献类型：
--
作者：
K. Sada;Naotaka Shiomi;M. Miyata
有机晶体材料的分子设计是有机固体化学领域的一个重要研究方向，它具有可控制大小、形状、手性和化学环境的纳米空腔。然而，纳米空腔的微调还处于起步阶段3,4，因为很少有坚固的结构基序可以构建不受化学修饰的不变3D框架。本文提出了一种由传统主体化合物和可调节次级组分组成的二元主体化合物调节纳米空腔的新策略。该系统以最佳的分辨率为我们提供了一系列具有控制尺寸和形状的宿主腔。脱氧胆酸(1)是形成分子通道的宿主化合物之一。包合物和晶体状态下的特定有机反应已经被很好地记录下来。6,7我们的分子腔微调策略依赖于1烷基铵盐坚固的多孔双层结构。羧酸阴离子构成具有分子空腔的三维框架，烷基铵阳离子部分占据空腔。客体分子包含在剩余的空隙空间中。因此，可以通过修改后一个主部件来设计和控制空间尺寸和环境。用过量的2a-e处理1的THF溶液，使3a-e成为白色沉淀，产率很高（方案1）。通过x射线晶体学和包合晶体的形成，对它们进行了各种有机化合物的再结晶。虽然1的羧酸阴离子的位置在所有5个宿主体系中都已确定，但铵离子和客体化合物的烷基在三维空间中的无序性非常严重，因此羧酸阴离子只能各向同性地细化。然而，与适当的客体化合物的3a-e的晶体结构都是同形晶体。8
Molecular design of organic crystalline materials that have nanocavities with controlled size, shape, chirality, and chemical environment is of great interest in organic solid-state chemistry. 1, 2 However, fine-tuning of nanocavities is in its infancy3, 4 because there have been few robust structural motifs that construct unchanged 3D framework against chemical modification. We present herein a novel strategy for tuning nanocavities by the binary host compounds that consist of the traditional host compound and the adjustable secondary components. This system gives us a series of the host cavities with the controlled size and shape at the finest resolution.Deoxycholic acid (1) is one of the host compounds that forms molecular channels. 5 Inclusion complexes and the specific organic reactions in the crystalline state have been already well documented. 6, 7 Our strategy for the fine-tuning of the molecular cavities relies on the robust porous bilayer structure of alkylammonium salts of 1. The carboxylate anions construct a 3D framework with molecular cavities, and the alkylammonium cations partially occupy the cavities. Guest molecules are included in the remaining void space. Consequently, the steric dimensions and environments can be designed and controlled by the modification of the latter host components. THF solutions of 1 were treated with excess 2a-e to give 3a-e as white precipitates in good yields (Scheme 1). They were subjected to recrystallization from various organic compounds for X-ray crystallography and the formation of inclusion crystals. Although the positions of the carboxylate anion of 1 were established for all five of the host systems, disorder of the alkyl groups of the ammonium cation and the guest compounds in 3d was so severe that the carboxylate anion only can be refined isotropically. However, crystal structures of 3a-e with the appropriate guest compounds are all isomorphic crystals. 8 A