Ion pair cooperative binding of potassium salts by new rhenium(I) bipyridine crown ether receptors.

Journal article

The new rhenium(I) bipyridine crown ether receptors 1-4 have been prepared and their ion pair recognition properties examined. The crystal structure of [1.KCl](2).2H(2)O demonstrates that potassium is coordinated by benzo-18-crown-6 and chloride is hydrogen bonded to the amide groups. Receptor 3 extracts solid KCl and KOAc into chloroform via ion pair complexation. NMR and emission titration studies with receptors 1-4 and KCl/KOAc show that cobound potassium enhances anion binding strength by electrostatic and conformational effects. Significant cooperative interactions are observed between the anion and cation sites for host 4 in CH(3)CN. This molecule coordinates potassium to form a 1:1 intramolecular sandwich complex, which preorganizes the host for acetate binding.

Authors: Uppadine, L; Redman, J; Dent, S; Drew, MG; Beer, P

• Publication status: Published
• Journal: Inorganic chemistry
• Volume: 40
• Issue: 12
• Pages: 2860-2869
• Publication date: 2001-06-01
• DOI: 10.1021/ic001450v
• EISSN: 1520-510X
• ISSN: 0020-1669
• Language: English
• Keywords: Cations, Monovalent; Potassium Chloride; 2,2'-Dipyridyl; Crystallography, X-Ray; Spectrometry, Mass, Fast Atom Bombardment; Rhenium; Magnetic Resonance Spectroscopy; Ethers, Cyclic; Organometallic Compounds; Anions; Acetates