Trivalent lanthanide metal complexes of a tetradentate nitrogen donor-synthesis and characterization

Chelate compounds of La(III), Ce(III), Pr(III), Nd(III), Dy(III), Sm(III), Eu(III), Yb(III) and Lu(III) with N,N'-ethylene-bis-(2-aminobenzamide), EBAB, have been prepared by the reaction between the respective metal chlorides and the ligand in methyl alcohol. The complexes have been characterized by the elemental analysis, conductance, magnetic and thermal studies and IR, electronic and 1H NMR spectral investigations. The 1:1 complexes are found to be non-ionic with the molecular formula Ln(EBAB)Cl3. The IR and NMR spectra of complexes confirm that EBAB acts as a tetradentate ligand coordinating through two amine and two amide nitrogen atoms. Based on the results obtained a tentative structure of monocapped trigonal prism, has been proposed for these seven coordinated complexes of lanthanides. (author). 20 refs., 1 fig., 3 tabs