Synthesis, structures and magnetic properties of 1D to 3D coordinated polymers based on series of flexible sulfide ligands

Five complexes [Mn2O(L1)4]n (1), [Co(L2)(H2O)2]n (2), [Co(L3)2(H2O)2]n (3) and [Co(L4)2(4,4′-bpy)(H2O)]n (4) were obtained by using flexible organic ligands HL1, HL2, HL3, and HL4 in hydrothermal systems with cobalt, copper and manganese salts respectively (HL1 = 2-(4-pyridylmethylthio)benzoic acid, HL2 = 4-(4-pyridylmethylthio)benzoic acid, HL3 = 2-(3-pyridylmethylthio)benzoic acid, HL4 = 4-(2-pyridylmethylthio)benzoic acid). The five complexes have been characterized by X-ray single crystal diffraction, FT-IR spectrum and elemental analysis. Complex 1 is assembled to a 3D porous framework with Mn2O units as nodes. Complex 2 shows 2D layer networks comprised of six-coordinated Co2+ centers and L2− anionic ions. Complexes 3 and 4 have different 1D double or single chain structures. Various non-covalent bonds such as hydrogen bonds, π⋯π interactions, H-bond grids and S⋯S weak interactions lead to interesting supramolecular frameworks. DC (direct current) temperature dependent magnetic susceptibilities suggest weak antiferromagnetic behaviors exist in 1, and single ion paramagnetic along with spin-orbit coupling behavior dominate in 3 and 4.

Graphical abstractFour complexes with 1D to 3D frameworks have been prepared from hydrothermal systems containing cobalt and manganese salts and series of 2-(4-pyridylmethylthio)benzoic acid, 4-(4-pyridylmethylthio)benzoic acid, 2-(3-pyridylmethylthio)benzoic acid, and 4-(2-pyridylmethyl thio)benzoic acid.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Flexible sulfide ligands were used to synthesize Mn2+ and Co2+ coordination polymers. ► Complex 1–4 exhibit 3D to 1D coordination polymers. ► Interesting supramolecular is assembled by H-bond grids, S⋯S and π–π interactions. ► Antiferromagnetic behavior is observed in complexes 1 and 4.