Dinuclear\nRare-Earth β‑Diketiminates\nwith Bridging 3,5-Di<i>tert</i>-butyl-catecholates: Synthesis,\nStructure, and Single-Molecule Magnet Properties

The dinuclear β-diketiminato complex [L<sup>1</sup>ClDy(μ-Cl)<sub>3</sub>DyL<sup>1</sup>(THF)] (<b>1</b>) (L<sup>1</sup> = {2,6-<sup>i</sup>Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>–NC(Me)CHC(Me)N-2,6-<sup>i</sup>Pr<sub>2</sub>C<sub>6</sub>H<sub>3</sub>}<sup>−</sup>) was obtained by reaction\nof DyCl<sub>3</sub> with KL<sup>1</sup> in a molar ratio of 1:1 and\nused for the preparation of the mixed-ligand\ncomplex [L<sup>1</sup>Dy(μ-3,5-Cat)]<sub>2</sub> (<b>2</b>) by salt metathesis reaction with 3,5-CatK<sub>2</sub> (3,5-Cat\n−3,5-di-<i>tert</i>-butyl-catecholate). Reactions\nof 3,5-CatNa<sub>2</sub> with [L<sup>2</sup>LnCl<sub>2</sub>(THF)<sub>2</sub>] (Ln<sup>3+</sup> = Dy, Y) ligated with the less bulky ligand\nL<sup>2</sup> = {2,4,6-Me<sub>3</sub>C<sub>6</sub>H<sub>2</sub>–NC(Me)CHC(Me)N-2,4,6-Me<sub>3</sub>C<sub>6</sub>H<sub>2</sub>}<sup>−</sup> afforded the\nmixed-ligand THF-containing complexes [L<sup>2</sup>Ln(μ-3,5-Cat)(THF)]<sub>2</sub> (Ln<sup>3+</sup> = Dy (<b>3a</b>), Y (<b>3b</b>)). All new complexes were fully characterized, and the solid-state\nstructures were determined by single-crystal X-ray diffraction. Magnetic\nmeasurements revealed single-molecule magnet behavior for the dysprosium\ncomplexes. Sub-Kelvin μSQUID studies confirm the SMM character\nof the systems, while CASSCF calculation along with simulation of\nthe experimental data yields an antiferromagnetic interaction operating\nbetween the Dy<sup>3+</sup> ions.