Rare earth chelates of biacetylbis(benzoylhydrazone)

Synthesis and characterisation of chelates of trivalent rare earth metals, La, Pr, Nd, Sm, Gd, Ho, Er and Yb with an unusual schiff base, biacetyl bis (benzoyldrazone), are described. The chelates have been synthesised by an in situ process refluxing biacetyl, benzoylhydrazide and metal salts. Biacetyl bis (benzoylhydrazone) (BDH) acts as tetradentate ligand coordinating through enolic oxygen and azomethine nitrogen atoms. The chelates are characterised to be neutral six-coordinated octahedral complexes of the formula [M(BDH)(OH)(H2O)] by elemental analysis, conductance, magnetic electronic and infrared spectral measurements. (author)