Dinuclear Rare-Earth β-Diketiminates with Bridging 3,5-Ditert-butyl-catecholates: Synthesis, Structure, and
Svetlana V Klementyeva1, Michael T Gamer2, Michael Schulze3
1Institute of Nanotechnology, Karlsruhe Institute of Technology (KIT) Campus North, P.O. Box 3640, Karlsruhe 76021, Germany.
Abstract:
The dinuclear β-diketiminato complex [L1ClDy(μ-Cl)3DyL1(THF)] (1) (L1 = {2,6-iPr2C6H3-NC(Me)CHC(Me)N-2,6-iPr2C6H3}-) was obtained by reaction of DyCl3 with KL1 in a molar ratio of 1:1 and used for the preparation of the mixed-ligand complex [L1Dy(μ-3,5-Cat)]2 (2) by salt metathesis reaction with 3,5-CatK2 (3,5-Cat -3,5-di-tert-butyl-catecholate). Reactions of 3,5-CatNa2 with [L2LnCl2(THF)2] (Ln3+ = Dy, Y) ligated with the less bulky ligand L2 = {2,4,6-Me3C6H2-NC(Me)CHC(Me)N-2,4,6-Me3C6H2}- afforded the mixed-ligand THF-containing complexes [L2Ln(μ-3,5-Cat)(THF)]2 (Ln3+ = Dy (3a), Y (3b)). All new complexes were fully characterized, and the solid-state structures were determined by single-crystal X-ray diffraction. Magnetic measurements revealed single-molecule magnet behavior for the dysprosium complexes. Sub-Kelvin μSQUID studies confirm the SMM character of the systems, while CASSCF calculation along with simulation of the experimental data yields an antiferromagnetic interaction operating between the Dy3+ ions.
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