Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.

Issue 24, 2014
Previous Article Next Article

Tetraphosphonated thiophene ligand: mixing the soft and the hard

Author affiliations


The synthesis of ligand LTH8, based on a thiophene framework containing two bis(aminomethyldiphosphonate) functions in the ortho position to the central sulfur atom, is described, together with the characterization of the intermediate compounds. The physico-chemical properties of the ligand were first studied by means of potentiometry and UV-Vis absorption spectrophotometric titrations to determine its pK values. Six successive equilibrium constants were determined in aqueous solutions. The same means were then used to quantify the interactions of the ligand with Ni(II), Cu(II) and Zn(II). Following the conventional Irving–Williams trend, LT was shown to have the highest affinity towards Cu(II) (log K(CuLT) = 16.11(3)), while Zn(II) and Ni(II) showed similar values (log K(MLT) = 10.81(8) and 10.9(1), respectively), revealing a large selectivity of LT toward Cu(II). Based on a combination of UV-Vis absorption spectroscopy and EPR measurements as a function of pH, along with DFT calculations, the coordination behavior of the hard phosphonate, medium amino and soft thiophene entities are questioned regarding their coordination to the Cu atom.

Graphical abstract: Tetraphosphonated thiophene ligand: mixing the soft and the hard

Back to tab navigation

Supplementary files

Article information

12 Feb 2014
14 Apr 2014
First published
15 Apr 2014

Dalton Trans., 2014,43, 9070-9080
Article type
Author version available

Tetraphosphonated thiophene ligand: mixing the soft and the hard

J. Brandel, A. Lecointre, J. Kollek, S. Michel, V. Hubscher-Bruder, I. Déchamps-Olivier, C. Platas-Iglesias and L. J. Charbonnière, Dalton Trans., 2014, 43, 9070
DOI: 10.1039/C4DT00451E

Social activity

Search articles by author