Syntheses, structures, and magnetic properties of symmetric and dissymmetric ester-functionalized 3d-4f schiff base complexes
Résumé
Ester-functionalized bicompartmental Schiff base ligands and their 3d-Ln complexes (3d = NiII, CuII, or ZnII and Ln = GdIII, TbIII, or DyIII) are reported. The modularity of the Schiff base structure (i.e., symmetric ester group compared with dissymmetric ester group) is illustrated to highlight the possibility offered by the ester for facile functionalization at the periphery of the ligand, in addition to its electron-withdrawing effect on the complexing core. The introduction of a chiral pool (i.e., a menthyl group) at the ester functions led to a transfer of chirality to the coordination sphere of the Ln in the solid state. Several 3d-4f complexes were found to crystallize as (NO3–)- or (OH–)-bridged compounds. Crystal structures and magnetic behaviors are reported for all of the 3d-4f complexes.