Synthesis and structure of trans-bis-(4-amino-3-nitro-benzoato-κO)bis-(4-amino-3-nitro-benzoic acid-κO)di-aqua-manganese(II) dihydrate.

The manganese title complex, [Mn(C7H5N2O4)2(C7H6N2O4)2(H2O)2]·2H2O, is one of the first 4-amino 3-nitro-benzoic acid (4 A3NBA) monoligand metal complexes to be synthesized. It crystallizes in the centrosymmetric monoclinic space group P21/n with the complex mol-ecules located on inversion centers. Four 4 A3NBA ligand mol-ecules are monodentately coordinated by the Mn2+ ion through the carb-oxy-lic oxygen atoms while the other two positions of the inner coordination sphere are occupied by water mol-ecules, giving rise to a distorted octa-hedron, and two water mol-ecules are in the outer coordination sphere. There are two intra-molecular hydrogen bonds in the complex mol-ecule. The first is of the common N-H⋯O=N type, while the second is a rarely occurring very strong hydrogen bond in which a common proton is shared by two uncoordinated oxygen atoms of neighboring carboxyl-ate groups. In the crystal, an intricate system of inter-molecular hydrogen bonds links the complex mol-ecules into a three-dimensional-network.

Tetra-aqua-(ethane-1,2-di-amine-κ2N,N')nickel(II) naphthalene-1,5-di-sulfonate dihydrate.

The reaction of ethane-1,2-di-amine (en, C2H8N2), the sodium salt of naphthalene-1,5-di-sulfonic acid (H2NDS, C10H8O6S2), and nickel sulfate in an aqueous solution resulted in the formation of the title salt, [Ni(C2H8N2)(H2O)4](C10H6O6S2)·2H2O or [Ni(en)(H2O)4](NDS)·2H2O. In the asymmetric unit, one half of an [Ni(en)(H2O)4]2+ cation and one half of an NDS2- anion, and one water mol-ecule of crystallization are present. The Ni2+ cation in the complex is positioned on a twofold rotation axis and exhibits a slight tetra-gonal distortion of the cis-NiO4N2 octa-hedron, with an Ni-N bond length of 2.0782 (16) Å, and Ni-O bond lengths of 2.1170 (13) Šand 2.0648 (14) Å. The anion is completed by inversion symmetry. In the extended structure, the cations, anions, and non-coordinating water mol-ecules are connected by inter-molecular N-H⋯O and O-H⋯O hydrogen bonding, as well as C-H⋯π inter-actions, forming a three-dimensional network.

Synthesis, crystal structure and Hirshfeld surface analysis of catena-poly[[bis-(semicarbazide-κ2 N,O)copper(II)]-µ-sulfato-κ2 O:O'].

The title polymer, [Cu(SO4)(CH5N3O)2] n , has been synthesized from aqueous solutions of CuSO4 and semicarbazide. In the crystal structure, the CuII atoms are chelated by two neutral semicarbazide mol-ecules through the oxygen atom and a nitro-gen atom of the amino group. The remaining two positions of the Jahn-Teller-distorted octa-hedral coordination sphere are occupied by oxygen atoms of two sulfate anions in the axial positions. The coordination bonds of the latter associate the polyhedra into polymeric chains running parallel to the c axis. There is a weak intra-molecular hydrogen bond between the N-H group and an oxygen atom of the SO4 2- anion. Thirteen relatively weak inter-molecular hydrogen-bonding inter-actions link the chains into a three-dimensional network. Hirshfeld surface analysis revealed that 64.7% of the inter-molecular inter-actions are from O⋯H/H⋯O contacts and 20.1% from H⋯H contacts. Other inter-actions such as N⋯H/H⋯N or C⋯H/H⋯C contribute less to the crystal packing.

Crystal structure of trans-bis-(di-ethano-lamine-κ(3) O,N,O')manganese(II) bis-(3-amino-benzoate).

Reaction of m-amino-benzoic acid (MABA), di-ethano-lamine (DEA) and MnCl2·4H2O led to the formation of the title salt, [Mn(C4H11NO2)2](C7H6NO2)2. In the complex cation, the Mn(2+) ion is located on an inversion centre and is coordinated by two symmetry-related tridentate DEA mol-ecules, leading to the formation of a slightly distorted MnN2O4 octa-hedron. The MABA(-) counter-anions are connected to the complex ion by a pair of rather strong O-H⋯O hydrogen bonds, yielding a 1:2 supra-molecular aggregate. Much weaker N-H⋯O hydrogen bonds connect neighbouring aggregates into a three-dimensional network structure.

Crystal structure of bis-(tri-ethano-lamine-κ(3) N,O,O')nickel(II) bis-(3-hy-droxy-benzoate) tetra-hydrate.

The reaction of 3-hy-droxy-benzoic (m-hy-droxy-benzoic) acid (MHBA), tri-ethano-lamine (TEA) and Ni(NO3)2 in aqueous solution led to formation of the hydrated title salt, [Ni(C6H15NO3)2](C7H5O3)·4H2O. In the complex cation, the Ni(2+) ion is located on an inversion centre. Two symmetry-related TEA ligands occupy all coordination sites in an N,O,O'-tridentate coordination, leading to a slightly distorted NiN2O4 octa-hedron. Two ethanol groups of each TEA ligand form two five-membered chelate rings around Ni(2+), while the third ethanol group does not coordinate to the metal atom. Two MHBA(-) anions in the benzoate form are situated in the outer coordination sphere for charge compensation. An intricate network of hydrogen bonds between the free and coordinating hy-droxy groups of the TEA ligands, the O atoms of the MHBA(-) anions and the water mol-ecules leads to the formation of a two-dimensional structure extending parallel to (010).