Lanthanide ion(III) complexes of deprotonated p-tert-butylcalix[n]arene in acetonitrile
Written by sctunisie no commentsThe anionic calixarene derivatives ('calixanions') have been obtained by the reaction of weak bases such as triethylamine, with p-tert-butylcalix[n]arenes in MeCN. To clarify the involvement of the solvent in deprotonation, comparison of media effect (MeCN and DMF) and computational methods (Frontier Molecular Orbital Theory) are employed. The binding of representative lanthanide(III) cations with p-tert-butylcalix[n]arenes (n=4, 6, 8) anions form in MeCN monomeric complexes in the case of tetra and hexa calixarenes, and dimeric complexes with the larger calixarene ,calix[8]arene. The conditional stability constants of the lanthanum (La3+), europium (Eu3+), gadolinium (Gd3+) and terbium (Tb3+) complexes were determined. In addition, it was found that deprotonated p-tert-butylcalix[n] arenes (n=4, 8) present an affinity toward europium, while p-tert-butylcalix[6]arene anion shows a significant selectivity for lanthane cation.
I. Hamzi, K. Essalah, R. Abidi
Calixanions, Lanthanides (III), Complexation, Absorption spectrophotometry, Frontier Molecular Orbital Theory (FMO)
Pages 21-30
