Latest News:Index Copernicus Value (ICV) for 2013 was 3.59; 2014 was 58.17; 2015 was 64.83 and in 2016 is 79.75
: The complexing properties of some pyridine amide calix[4]arenes have been carried out in acetonitrile and monitored by UV spectrophotometry. Their considered targets were several heavy metals (Hg2+, Cd2+ and Pb2+) and trivalent lanthanides cations (La3+, Nd3+, Eu3+, Gd3+ and Yb3+). The three derivatives (1, 2 and 3) form mononuclear complexes with heavy metal and lanthanide cations, except in the case of calixarene 2, which formed simultaneously mononuclear and binuclear species with Pb2+. The results show that the complexation is the main factor affecting the extraction with the tetra-substituted ligands (1, 2), in contrast with the di-substituted ligand 3.