Bile acid-based cyclic bisbenzimidazolium receptors for anion recognition: highly improved receptors for fluoride and chloride ions.
The anion binding properties of bile acid-based cyclic bisbenzimidazolium receptors 6-8 bridged with m-xylene, p-xylene, and 2,6-dimethylpyridine have been studied. Receptors 6 and 7 exhibit much higher binding affinity for fluoride and chloride ions, respectively, as compared to the imidazolium receptors 1 and 2. Receptor 8, however, shows high selectivity but very low binding affinity for anions due to the presence of pyridyl nitrogen. The single-crystal X-ray structure of imidazolium receptor 10-(Br)2 containing pyridyl spacer reveals the binding pattern.
Khatri
Vijay K
VK
Department of Chemistry, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
Chahar
Mamta
M
Pavani
K
K
Pandey
Pramod S
PS
D000838:Anions / Q000737:chemistry; D001562:Benzimidazoles / Q000737:chemistry*; D001647:Bile Acids and Salts / Q000737:chemistry*; D002712:Chlorides / Q000737:chemistry*; D018360:Crystallography, X-Ray; D005459:Fluorides / Q000737:chemistry*; D007477:Ions / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D011725:Pyridines / Q000737:chemistry; D013237:Stereoisomerism; D014992:Xylenes / Q000737:chemistry
D000838:Anions; D001562:Benzimidazoles; D001647:Bile Acids and Salts; D002712:Chlorides; D007477:Ions; D011725:Pyridines; D014992:Xylenes; C031286:4-xylene; C031285:3-xylene; D005459:Fluorides