Switching Ion Binding Selectivity of Thiacalix[4]arene Monocrowns at Liquid–Liquid and 2D-Confined Interfaces

International Journal of Molecular Sciences

Viktor Syakaev¹  Olga Babaeva¹  Tatiana Gerasimova¹  Sergey Katsyuba¹  Anton Muravev¹  Igor Antipin²  Svetlana Solovieva²  Ayrat Yakupov²  Ramil Nugmanov²  Guliya Nizameeva³  Sofiya Selektor⁴  Ekaterina Trushina⁵ 

[1]Arbuzov Institute of Organic and Physical Chemistry, FRC Kazan Scientific Center, Russian Academy of Sciences, Arbuzov Str. 8, 420088 Kazan, Russia

[2]Butlerov Institute of Chemistry, Kazan Federal University, Kremlevskaya Str. 18, 420008 Kazan, Russia

[3]Department of Physics, Kazan National Research Technological University, Karl Marx Str. 68, 420015 Kazan, Russia

[4]Frumkin Institute of Physical Chemistry and Electrochemistry, Russian Academy of Sciences, Leninsky pr. 31, 119071 Moscow, Russia

[5]School of Chemistry, University of Glasgow, University Avenue, Glasgow G12 8QQ, UK

关键词: thiacalix[4]arene monocrowns;    Langmuir monolayers;    liquid-phase extraction;    ion binding;    surface potential;    UV/visible reflection–absorption spectroscopy;   

DOI  :  10.3390/ijms22073535

来源: DOAJ

【 摘 要 】

Understanding the interaction of ions with organic receptors in confined space is of fundamental importance and could advance nanoelectronics and sensor design. In this work, metal ion complexation of conformationally varied thiacalix[4]monocrowns bearing lower-rim hydroxy (type I), dodecyloxy (type II), or methoxy (type III) fragments was evaluated. At the liquid–liquid interface, alkylated thiacalixcrowns-5(6) selectively extract alkali metal ions according to the induced-fit concept, whereas crown-4 receptors were ineffective due to distortion of the crown-ether cavity, as predicted by quantum-chemical calculations. In type-I ligands, alkali-metal ion extraction by the solvent-accessible crown-ether cavity was prevented, which resulted in competitive Ag⁺ extraction by sulfide bridges. Surprisingly, amphiphilic type-I/II conjugates moderately extracted other metal ions, which was attributed to calixarene aggregation in salt aqueous phase and supported by dynamic light scattering measurements. Cation–monolayer interactions at the air–water interface were monitored by surface pressure/potential measurements and UV/visible reflection–absorption spectroscopy. Topology-varied selectivity was evidenced, towards Sr²⁺ (crown-4), K⁺ (crown-5), and Ag⁺ (crown-6) in type-I receptors and Na⁺ (crown-4), Ca²⁺ (crown-5), and Cs⁺ (crown-6) in type-II receptors. Nuclear magnetic resonance and electronic absorption spectroscopy revealed exocyclic coordination in type-I ligands and cation–π interactions in type-II ligands.

【 授权许可】

Unknown