Synthesis of gadolinium(III) and samarium(III) complexes of new potentially heptadentate (N4O3) tripodal Schiff base ligands, and a theoretical study

The synthesis and characterization of two new potentially heptadentate N4O3 tripodal Schiff base ligands H3L1 and H3L2 are reported. The neutral gadolinium(III) and samarium(III) complexes, [Ln(L)], of these bulky ligands and also a gadolinium(III) complex of a previously known ligand, H3L3, were also synthesized and characterized by various spectroscopic methods. The relative capability of these ligands as well as their unsubstituted analogs to encapsulate a lanthanide ion, herein La(III), has been theoretically studied.