Sessler Jonathan L, Gross Dustin E, Cho Won-Seob, Lynch Vincent M, Schmidtchen Franz P, Bates Gareth W, Light Mark E, Gale Philip A
Department of Chemistry and Biochemistry, University of Texas at Austin, Texas 78712-0165, USA.
J Am Chem Soc. 2006 Sep 20;128(37):12281-8. doi: 10.1021/ja064012h.
The interaction of calixpyrrole with several chloride salts has been studied in the solid state by X-ray crystallography as well as in solution by isothermal titration calorimetry (ITC) and (1)H NMR spectroscopic titrations. The titration results in dimethylsulfoxide, acetonitrile, nitromethane, 1,2-dichloroethane, and dichloromethane, carried out using various chloride salts, specifically tetraethylammonium (TEA), tetrapropylammonium (TPA), tetrabutylammonium (TBA), tetraethylphosphonium (TEP), tetrabutylphosphonium (TBP), and tetraphenylphosphonium (TPhP), showed no dependence on method of measurement. The resulting affinity constants (K(a)), on the other hand, were found to be highly dependent on the choice of solvent with K(a)'s ranging from 10(2)-10(5) M(-1) being recorded in the test solvents used for this study. In dichloromethane, a strong dependence on the countercation was also seen, with the K(a)'s for the interaction with chloride ranging from 10(2)-10(4) M(-1). In the case of TPA, TBA, and TBP, the ITC data could not be fit to a 1:1 binding profile.
通过X射线晶体学在固态下以及通过等温滴定量热法（ITC）和¹H NMR光谱滴定法在溶液中研究了杯吡咯与几种氯化物盐的相互作用。使用各种氯化物盐，特别是四乙铵（TEA）、四丙铵（TPA）、四丁铵（TBA）、四乙鏻（TEP）、四丁鏻（TBP）和四苯基鏻（TPhP），在二甲基亚砜、乙腈、硝基甲烷、1,2 - 二氯乙烷和二氯甲烷中进行滴定，结果表明不依赖于测量方法。另一方面，发现所得的亲和常数（Kₐ）高度依赖于溶剂的选择，在本研究使用的测试溶剂中记录的Kₐ范围为10² - 10⁵ M⁻¹。在二氯甲烷中，还观察到对抗衡阳离子有很强的依赖性，与氯离子相互作用的Kₐ范围为10² - 10⁴ M⁻¹。在TPA、TBA和TBP的情况下，ITC数据不符合1:1的结合模式。
