Molecular Mn(II), Fe(III), and Dy(III) Complexes with the Pentadentate N3S2 Ligand

The first molecular complexes of paramagnetic 3d (Mn, Fe) and 4f (Dy) metals with the pentadentate N3S2 ligand 2,6-diacetylpyridine bis(4-N-(4-ethylphenyl)thiosemicarbazone) (H2L) were synthesized: [MnII(H2L)Cl(CH3OH)]Cl·2.5CH3OH (I), [FeIII(HL)Cl(CH3OH)]Cl (II), and [DyIII(L)(HL')]·4CH3OH (III). According to X-ray data (CCDC nos. 2 472 028 (I), 2 472 029 (II), 2 472 030 (III)), all complexes are mononuclear. Complexes of the 3d metals I and II have pentagonal-bipyramidal coordination of the magnetic center: the equatorial plane is formed by the pentadentate N3S2 ligand, and the apical positions are occupied by two Cl and O atoms of monodentate axial ligands. The chelating ligand is the neutral H2L in the Mn(II) complex and the monodeprotonated HL– in the Fe(III) complex. In the 4f-metal complex, two ligands are coordinated to one Dy(III) center: the doubly deprotonated L2– and the transformed ligand (HL')–, in which one S atom is substituted by a MeO group. As a result, the Dy ion has a nine-coordinate environment DyN7S2. The magnetic properties of the Fe(III) complex were studied.