Synthesis and characterization of lanthanide [Ln(L)]2 complexes of N4O3 amine phenol ligands with phenolate oxygen bridges: evidence for very weak magnetic exchange between lanthanide ions

Anion‐Induced Assembly of Hexacoordinate Rare‐Earth(III) Complexes

“…The mean value of the RE-O phenoxo distances (2.267, 2.274, and 2.271 Å for 1, 2, and 3, respectively) is in the range of those observed for rare-earth(III) complexes with similar Schiff base ligands. [11,13,15,18,19] The average carbon-nitrogen bond lengths for the imino group is 1.296, 1.290, and 1.289 Å for 1, 2, and 3, respectively, in agreement with the C=N distance. [13,15,19] Hydrogen atoms located on the three imino nitrogen atoms of each ligand are involved in intramolecular hydrogen bonds with the deprotonated phenol oxygen atoms, indicating that a proton migration is involved during coordination, which is similar to other reports on Schiff base rare-earth(III) complexes (1: av.…”

Lanthanide-Containing Molecular and Supramolecular Polymetallic Functional Assemblies

“…In this case, the highest temperature at which the magnetic susceptibility is maximum is expected in the case of 4f 7 (Gd(III)), 4f 5 (Sm(III)), and 4f 9 (Dy-(III)), in line with experimental data on [Ln(C 5 H 5 ) 2 -Br] 2 . 183 The magnetic behavior of Gd-Gd ( 4f 7 ) pairs is documented for several systems in which the metal ions are connected by bridging ligands, for instance, in coordination compounds, 184,185 podates 17,186 or complexes with calixarenes. 187 The examples listed in Table 2 show that the interaction is antiferromagnetic, with coupling constants J in the range -0.045 to -0.2 cm -1 , which is at least 1 to 2 orders of magnitude lower than that for Gd-Cu pairs, for instance.…”

Rhenium and technetium complexes from pentadentate (N3O2) and tetradentate (N2O2) Schiff base ligands

“…The bound dha-is obviously the hydrolyzed product of the original Schiff base. The ligated Schiff bases are known to be susceptible to metal-enhanced hydrolysis, as is known with some lanthanide complexes (22). The hydrolysis of Schiff bases coordinated to Tc(V) is important in the development of 9 9 m~c radiopharmaceuticals.…”