Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China.
Inorg Chem. 2011 Mar 7;50(5):1682-8. doi: 10.1021/ic1021609. Epub 2011 Jan 18.
The present work was devoted to an experimental investigation of the molecule-ion interaction between copper chloride (CuCl(2)) and β-cyclodextrin (CD) and its effect on the electrostatic interaction between Cu(2+) and Cl(-) ions. Our results gave an explicit description of the mutual effect between the interactions. First, the molecular arrangement and surface feature of β-CD experienced a fundamental structural change after interaction with Cu(2+) and Cl(-) ions, which was ascribed to a good separation of Cu(2+) from Cl(-) ions in β-CD matrix. Second, arguments based on electronic structural analysis provided a direct indication of the change in charge density distributions of Cu(2+) and Cl(-) ions in the presence of β-CD. Third, the actual occurrence of a second signal in the course of water release at a higher temperature suggested that the Cu(2+) ions were trapped in the form of hydrates in the crystal interstice of β-CD molecules. Fourth, comparison of the mass spectra indicated that the thermal decomposition of β-CD in the presence of CuCl(2) produced a series of interesting molecular ions: C(3)H(2)OH(+), C(4)H(3)OH(+), C(5)H(4)OH(+), and C(7)H(6)OH(+). We consider that this study is helpful in providing a new approach to the evaluation of the extent of the mutual effect between an inorganic salt and an organic molecule.
本工作致力于研究氯化铜（CuCl(2)）和β-环糊精（CD）之间的分子离子相互作用及其对 Cu(2+)和 Cl(-)离子静电相互作用的影响。我们的结果明确描述了相互作用之间的相互影响。首先，β-CD 的分子排列和表面特征在与 Cu(2+)和 Cl(-)离子相互作用后经历了根本性的结构变化，这归因于 Cu(2+)在β-CD 基质中与 Cl(-)离子的良好分离。其次，基于电子结构分析的论点提供了 Cu(2+)和 Cl(-)离子在存在β-CD 时电荷密度分布变化的直接指示。第三，在较高温度下水释放过程中出现第二个信号的实际发生表明 Cu(2+)离子以水合物的形式被捕获在β-CD 分子的晶体间隙中。第四，质谱比较表明，在 CuCl(2)存在下β-CD 的热分解产生了一系列有趣的分子离子：C(3)H(2)OH(+)、C(4)H(3)OH(+)、C(5)H(4)OH(+)和 C(7)H(6)OH(+)。我们认为这项研究有助于提供一种新方法来评估无机盐和有机分子之间相互作用的程度。
