The interaction between aluminium ion (Al) and quinolic acid (L) in acidic aqueous solution was investigated by potentiometry and 13 C and 27 Al NMR spectroscopy. In the 27 Al NMR spectra, two peaks were observed at 8 and 15.6 ppm, which were assigned to AlL and AlL 2 complexes, respectively. The 13 C NMR spectra provide clear evidence that the L acts as a bidentate ligand and that the L coordinates with a nitrogen atom and an oxygen atom of the adjacent carboxylic group to form a chelate complex with a five-membered ring. From a potentiometric study, the formation constants (log β 1 and log β 2 ) for the AlL and AlL 2 complexes were estimated to be 4.52 ± 0.02 and 7.99 ± 0.05, respectively.
All Science Journal Classification (ASJC) codes
- Analytical Chemistry