Carboxylate-Decorated Aggregation of Octanuclear Co₄Ln₄ (Ln = Dy, Ho, Yb) Complexes from Ligand-Controlled Hydrolysis: Synthesis, Structures, and Magnetic Properties

One-pot reactions of an asymmetric carboxy-ether-phenol based Schiff base H2L (2-((2-hydroxy-3-methoxybenzylidene)amino)benzoic acid) with selected Ln(NO3)3·nH2O and [Co2(μ-OH2)(O2CCMe3)4(HO2CCMe3)4] (Co2-Piv) in basic MeOH medium resulted a family three octanuclear complexes, [CoII4LnIII4L4(μ1,3-Piv)4(μ1,1,3-Piv)2(η1-Piv)2(μ3-OH)4(MeOH)2]·mMeOH·nH2O (Ln = Dy; m 3, n 1 (1), Ho; 4, 0 (2), Yb; (3)). The coordination aggregates thus obtained were nicely sustained by four ligand anions eight externally added carboxylate showing different modes intermetallic connectivity. options for incorporating 4f ions investigative synthesis, without altering the resulting core structure, successful representative examples. Single-crystal X-ray diffraction studies revealed that compounds are isostructural built from two initially formed partial dicubane-type Co2Ln2L2 units. In each tetranuclear parts, metal ion centers held together L2-, μ3-HO-, Piv- bridges, one terminal Piv-, MeOH. Four ends L2- units responsible connecting Co2Ln2 into structures. unique distortion around CoII is achieved facile bigger to adjacent hard OO sites. further maintained presence COO- groups L2-. dc magnetic susceptibility data ferromagnetic coupling between LnIII within series, whereas ac measurements identified only 1, having highly anisotropic DyIII ion, as single-molecule magnet absence any external field, energy barrier Ueff 12.5 K.