Synthesis and Characterization of Dendrimeric Bridged Salen/Saloph Complexes and Investigation of Their Magnetic and Thermal Behaviors

Eight new multinuclear Fe(III) and Cr(III) complexes involving tetradentate schiff bases N,N'-bis(salicylidene)ethylenediamine (salenH(2)) or N,N'-bis(salicylidene)benzene-1,2-diamine (salophH(2)) and the two new ligands 4,4',4 '',4''',4'''',4'''''-[1,3,5-trianzine-2,4,6-triyltris(nitrilomethylidyne-4,1-phenyl-eneoxy-1,3,5-trianzine-6,2,4-triyldiimino)]hexakis[benzoic acid] (4) or 5,5',5 '',5''',5'''',5'''''-[1,3,4-trianzine-2,4,6-triyltris(nitrilomethylidyne-4,1-phenyleneoxy-1,3,5-trianzine-6,2,4-trianzine-6,2,4-triyldiimino)]hexakis[benzene-1,3-dicarboxylic acid] (5) were synthesized (schemes 1 and 2) and characterized by means of (1)H-NMR and FT-IR spectroscopy, elemental analysis, LC/MS analysis, AAS (atomic-absorption spectrum) analysis, thermal analyses, and magnetic-susceptibility measurements. The complexes can also be characterized as low-spin distorted-octahedral Fe(III) and Cr(III) complexes bridged by carboxylato moieties.