Synthesis and Theoretical Study of Gadolinium(III)Complex of Heptadentate(N4O3)Tripodal Schiff Base Ligand

摘要

A new potentially heptadentate(N4O3)Schiff base ligand {N[(CH2)2N = CH(2-OH-5-BrC6H3)]2[(CH2)3N = CH(2-OH-5-BrC6H3)]}(H3L)was synthesized and characterized by elemental analysis and various spectroscopic methods.This ligand was derived from the condensation reaction of a tripodal tetraamine ligand,bis(2-aminoethyl)(3-aminopropyl)amine(pee)with 3 equiv.of 5-bromosalicylaldehyde.The neutral gadolinium(III)complex of this bulky ligand was also synthesized.The complex was characterized by microanalysis and IR spectra.The capability of H3L as well as its unsubstituted analogs to encapsulate a lanthanide ion,herein La(III),has been theoretically studied by ab initio restricted Hartree-Fock(RHF)and density functional B3LYP methods.