Jb. Cooper et al., Heteroditopic rhenium(I) and ruthenium(II) bipyridyl calix[4]arene receptors for binding cation-anion ion pairs, J CHEM S DA, (4), 2001, pp. 392-401
Citations number
26
Categorie Soggetti
Inorganic & Nuclear Chemistry
Journal title
JOURNAL OF THE CHEMICAL SOCIETY-DALTON TRANSACTIONS
New heteroditopic ion pair receptors that contain rhenium(I) and ruthenium(
II) bipyridyl amide anion recognition sites covalently linked to a lower ri
m calix[4]arene tetraester alkali metal cation binding site have been prepa
red and shown to bind alkali metal (Li+, Na+)-halide (Br-, I-) ion pair spe
cies. Proton NMR titration studies reveal the lower rim ester co-bound alka
li metal cation significantly enhances the strength of bromide and iodide b
inding in acetonitrile solutions with the largest positive co-operative bin
ding effect of sixtyfold observed with bromide and the lithium complex of o
ne receptor. Solid/liquid extraction experiments show two of the receptors
are capable of solubilising NaCl and NaOAc in dichloromethane solutions.