Synthesis, structural characterizations, spectroscopic and magnetic properties of MnII and MnIII complexes with an unprecedented bridging coordination mode of 2-salicylichydrazono-1,3-dithiolane ligand

Two new complexes [MnIII(HL)2(acac)] and [MnII(HL)2]n have been obtained by reacting manganese(III) acetylacetonate monohydrate or manganese(II) chloride monohydrate with 2-salicylichydrazono-1,3-dithiolane ligand (H2L). Both compounds have been fully characterized by spectroscopic methods and single crystal X-ray diffraction. In the solid state, the molecular packing are described and discussed in term of weak H-bonds and short contacts. The unprecedented bridging coordination mode of this ligand lead to the first 2-salicylichydrazono-1,3-dithiolane-bridged coordination polymer [MnII(HL)2]n. The EPR spectrum of this compound was obtained with g ≈ 2.07, corresponding to a manganese ion (+II) in octahedral high-spin coordination sphere. The MnII complex exhibit paramagnetic behavior corresponding to quasi-isolated metal centers.

Graphical abstractTwo new complexes with 2-salicylichydrazono-1,3-dithiolane ligand (H2L) have been obtained by reacting manganese (III) acetylacetonate monohydrate or manganese (II) chloride with 2-salicylichydrazono-1,3-dithiolane ligand. Both compounds have been fully characterized by spectroscopic methods and single crystal X-ray diffraction. The unprecedented bridging coordination mode of this ligand lead to the first 2-salicylichydrazono-1,3-dithiolane-bridged coordination polymer.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Two new Mn+III complexes with 2-salicylichydrazono-1,3-dithiolane ligand obtained. ► Crystal structures of monomeric as well as polymeric species determined. ► Unprecedented bridging coordination mode for the 2-salicylichydrazono-1,3-dithiolane ligand.