{4,4',6,6'-Tetra-iodo-2,2'-[propane-1,3-diylbis(nitrilo-methanylyl-idene)]diphenolato-κ(4)O,N,N',O'}nickel(II).

The asymmetric unit of the title compound, [Ni(C(17)H(12)I(4)N(2)O(2))], comprises half of a Schiff base complex. The Ni(II) and central C atom of the propyl chain are located on a twofold rotation axis. The geometry around the Ni(II) atom is square planar, supported by the N(2)O(2) donor atoms of the coordinated ligand. In the crystal, there are no significant inter-molecular inter-actions present. The crystal studied was a non-merohedral twin with a refined twin component ratio of 0.944 (1):0.056 (1).

4,4',6,6'-Tetra-chloro-2,2'-[(1E,1'E)-propane-1,3-diylbis(nitrilo-methanylyl-idene)]diphenol.

The title compound, C(17)H(14)Cl(4)N(2)O(2), is generated by crystallographic twofold symmetry. The two benzene rings are inclined to one another by 80.17 (10)°. There are two intra-molecular O-H⋯N hydrogen bonds, which make S(6) ring motifs. In the crystal, mol-ecules are linked by C-H⋯O and weak C-H⋯Cl inter-actions, forming a three-dimensional network.

4,4',6,6'-Tetra-bromo-2,2'-[(E,E)-ethane-1,2-diylbis(nitrilo-methanylyl-idene)]di-phenol.

The asymmetric unit of the title compound, C(16)H(12)Br(4)N(2)O(2), comprises half of a potential tetra-dentate Schiff base ligand. The whole mol-ecule is generated by an inversion center located in the middle of the C-C bond of the ethyl-ene segment. There are intra-molecular O-H⋯N hydrogen bonds making S(6) ring motifs. In the crystal, no significant inter-molecular inter-actions are observed.

2-[(Z)-(3-{[(Z)-2-Hy-droxy-3,5-diiodo-benzyl-idene]amino}-propyl-imino)-meth-yl]-4,6-diiodo-phenol.

In the title compound, C(17)H(14)I(4)N(2)O(2), there are two intra-molecular O-H⋯N hydrogen bonds, which make S(6) ring motifs. In the crystal, there are no significant inter-molecular inter-actions present.

catena-Poly[{µ(3)-4,4',6,6'-tetra-bromo-2,2'-[butane-1,4-diylbis(nitrilo-methan-ylyl-idene)]diphenolato}{µ(2)-4,4',6,6'-tetra-bromo-2,2'-[butane-1,4-diylbis(nitrilo-methanylyl-idene)]dipheno-lato}dicopper(II)].

The asymmetric unit of the title coordination polymer consists of a dinuclear neutral complex mol-ecule of formula [Cu(2)(C(18)H(14)Br(4)N(2)O(2))(2)](n). One of the Cu(II) ions is coordinated in a distorted square-planar geometry, whereas the other is coordinated in a distorted square-pyramidal geometry, the long apical Cu-O bond [2.885 (4) Å] of the square-pyramidal coordination being provided by a symmetry-related O atom creating a one-dimensional polymer along [010]. π-π stacking inter-actions [centroid-centroid distance = 3.783 (4) Å] and short inter-chain Br⋯Br inter-actions [3.6142 (12)-3.6797 (12) Å] are observed.

Bis(dimethyl-formamide-κO){4,4',6,6'-tetra-chloro-2,2-[butane-1,4-di-yl(nitrilo-methanylyl-idene)]diphenolato-κ(4)O,N,N',O'}nickel(II).

In the title Schiff base complex, [Ni(C(18)H(14)Cl(4)N(2)O(2))(C(3)H(7)NO)(2)], the geometry around the Ni(II) atom is distorted octa-hedral. It is coordinated by the N(2)O(2) donor atoms of the tetra-dentate Schiff base ligand and the O atoms of two dimethyl-formamide mol-ecules, which are cis to one another. The benzene rings are almost normal to each other [dihedral angle = 88.60 (14)°]. The various intra-molecular C-H⋯O hydrogen bonds make S(5) and S(6) ring motifs. In the crystal, mol-ecules are linked by pairs of weak C-H⋯Cl inter-actions, forming inversion dimers.

catena-Poly[{µ(3)-4,4',6,6'-tetra-chloro-2,2'-[butane-1,4-diylbis(nitrilo-methanyl-yl-idene)]diphenolato}{µ(2)-4,4',6,6'-tetra-chloro-2,2'-[butane-1,4-diylbis(nitrilo-methanylyl-idene)]diphenolato}dicopper(II)].

The asymmetric unit of the title compound, [Cu(2)(C(18)H(14)Cl(4)N(2)O(2))(2)](n), contains two independent Cu(II) ions which are bridged by a pair of 4,4',6,6'-tetra-chloro-2,2'-[butane-1,4-diylbis(nitrilo-methanylyl-idene)]diphenolate ligands, forming a dinuclear unit. One of the Cu(II) ions is coordinated in a distorted square-planar environment and the other is coordinated in a distorted square-pyramidal environment. The long apical Cu-O bond of the square-pyramidal coordinated Cu(II) ion is formed by a symmetry-related O atom, creating a one-dimensional polymer along [010]. In addition, short inter-molecular Cl⋯Cl distances [3.444 (2) Å] and weak π-π inter-actions [centroid-centroid distances = 3.736 (2)-3.875 (3) Å] are observed. The crystal studied was an inversion twin with a refined twin component ratio of 0.60 (1):0.40 (1).

4,6-Dichloro-2-[(E)-(2-{[(E)-3,5-dichloro-2-oxidobenzyl-idene]aza-nium-yl}eth-yl)iminiumylmeth-yl]phenolate.

The asymmetric unit of the title compound, C(16)H(12)Cl(4)N(2)O(2), comprises half of a potentially tetra-dentate Schiff base ligand, located about a twofold rotation axis which bis-ects the central C-C bond of the ethane-1,2-diamine group. In the solid state, the compound exists in the zwitterionic form. There are two intra-molecular N-H⋯O hydrogen bonds making S(6) ring motifs. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming two-dimensional frameworks which lie parallel to (100). There are also short Cl⋯Cl [3.4395 (9) Å] contacts present.

4,6-Dichloro-2-((E)-{4-[(E)-3,5-dichloro-2-hy-droxy-benzyl-idene-amino]-butyl-imino}-meth-yl)phenol.

The asymmetric unit of the title compound, C(18)H(16)Cl(4)N(2)O(2), comprises half of a potentially tetra-dentate Schiff base ligand. It is located about a twofold rotation axis that bis-ects the central C-C bond of the butane-1,4-diamine group. There are two intra-molecular O-H⋯N hydrogen bonds making S(6) ring motifs. In the crystal, mol-ecules are linked by pairs of weak C-H⋯Cl inter-actions, forming inversion dimers, which are further connected by C-H⋯O hydrogen bonds into two-dimensional frameworks that lie parallel to (001).

4,6-Dibromo-2-[(E)-(4-{[(E)-3,5-dibromo-2-hy-droxy-benzyl-idene]amino}-butyl)-imino-meth-yl]phenol.

The asymmetric unit of the title compound, C(18)H(16)Br(4)N(2)O(2), comprises half the molecule, which is located adjacent to an inversion centre at the mid-point of the central C-C bond of the butane-1,4-diamine segment. There are two intra-molecular O-H⋯N hydrogen bonds making S(6) ring motifs. In the crystal, mol-ecules are linked by pairs of weak C-H⋯Br inter-actions into chains along [101], which include R(2) (2)(8) ring motifs. These chains are further linked by C-H⋯O hydrogen bonds, forming a three-dimensional network.

(E)-1-(2-Hy-droxy-5-meth-oxy-benzyl-idene)thio-semicarbazide.

In the title mol-ecule, C(9)H(11)N(3)O(2)S, an intra-molecular O-H⋯N hydrogen bond generates an S(6) ring motif. In the crystal, mol-ecules are linked via pairs of N-H⋯S inter-actions, forming inversion dimers with R(2) (2)(8) ring motifs. These dimers are further linked via N-H⋯S and N-H⋯O hydrogen bonds, forming a two-dimensional network lying parallel to (100). The crystal structure is further stabilized by inter-molecular π-π inter-actions [centroid-centroid distance = 3.7972 (9) Å].

(E)-1-(3-Eth-oxy-2-hy-droxy-benzyl-idene)thio-semicarbazide.

The title compound, C(10)H(13)N(3)O(2)S, crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. In the crystal, the A and B mol-ecules are linked via pairs of N-H⋯O and O-H⋯S hydrogen bonds, forming dimers with R(2) (2)(14) and R(2) (2)(6) ring motifs. These dimers are linked via a pair of N-H⋯S hydrogen bonds with an R(2) (2)(8) ring motif, forming chains propagating along the c-axis direction. The crystal was refined as an inversion twin with a final BASF ratio of 0.54 (11):0.46 (11).