The Structure and Properties of Fe(II) 1,10-Phenanthroline-Thiobarbiturate

The structure of the mononuclear complex [Fe(Bipy)(H2O)2(Htba)2]∙6H2O (I), where Bipy – 2,2’-dipyridine, H2tba – 2-thiobarbituric acid (C4H4N2O2S), was determined by single crystal X-ray diffraction technique (cif-file CCDC No. 1831367). Crystals I are rhombic: a = 17.4697 (7), b = 11.7738 (4), c = 13.4314 (5) Å, V = 2762.6(2) Å3, space group Pnma, Z = 4. Two nitrogen atoms of the Bipy molecule and two water molecules are located in the equatorial plane of the octahedral complex, and two S-coordinated Htba− ions the axial positions are occupied. The structure is stabilized by N−H∙∙∙O, O−H∙∙∙O, С−H∙∙∙O, C−H∙∙∙S intermolecular hydrogen bonds and π–π interaction between Bipy and Htba−. The compound is characterized by the methods of powder X-ray diffraction, thermal analysis, and IR spectroscopy

μ-4,4′-Bipyridine-κ2N:N′-bis[tetraaqua(4,4′-bipyridine-κN)dimanganese(II)] bis(4-aminobenzoate) bis(perchlorate)–4,4′-bipyridine–water (1/2/4): a supramolecular system constructed by π–π and hydrogen-bond interactions

The title dinuclear manganese compound, [Mn2(C10H8N2)3(H2O)8](C7H6NO2)2(ClO4)2·2C10H8N2·4H2O, (I), has an inversion center located midway between the MnIIions. Each MnIIion has a distorted octahedral coordination environment, defined by two mutuallycisN atoms from two different 4,4′-bipyridine (4,4′-bipy) ligands and four O atoms from four water molecules. The asymmetric unit contains cationic [Mn(4,4′-bipy)1.5(H2O)4]2+, one isolated 4,4′-bipy molecule, one 4-aminobenzoate ion, one disordered perchlorate ion and two uncoordinated water molecules. In the dinuclear manganese cationic unit, one 4,4′-bipy acts as a bidentate bridging ligand between two MnIIions, while the other two act only as monodentate terminal ligands, giving rise to a `Z-type' [Mn2(4,4′-bipy)3(H2O)8] host unit. These host units are linked to each otherviaface-to-face π–π stacking interactions between monodentate terminal 4,4′-bipy ligands, generating a zigzag chain. The corners of these chains, defined by Mn(OH)4units, are surrounded by the solvent water molecules and the carboxylate O atoms of the 4-aminobenzoate ions, and all of these are connected to each otherviastrong O—H...O hydrogen-bond interactions, leading to a three-dimensional grid network with a large cavity running along thebaxis of the unit cell. The isolated 4,4′-bipy molecules, the 4-aminobenzoate and perchlorate anions and the water molecules are encapsulated in the cavities by numerous hydrogen-bond interactions.