1-[2-(Pyrazin-2-ylsulfan-yl)eth-yl]pyrazine-2(1H)-thione.

The title multifunctional twisted organic ligand, C(10)H(10)N(4)S(2), contains a short C=S bond [1.671 (2) Å]. The dihedral angle between the two pyrazine rings is 39.83 (6)°. In the crystal, inter-molecular C-H⋯N and C-H⋯S hydrogen bonds result in the formation of a supra-molecular network.

Poly[tris-(µ(3)-2-amino-ethane-sulfonato)-cobalt(II)potassium].

The title compound, [CoK(C(2)H(6)NO(3)S)(3)](n), is isotypic with its Ni(II) analogue. The Co(II) atom is chelated by the three taurinate ligands in a distorted octa-hedral geometry and in a facial manner. Each taurinate ligand bridges two K(+) ions via its sulfonate group, forming a three-dimensional framework. Weak N-H⋯O hydrogen bonding is observed in the crystal structure.

Bis[2-(2-pyridylmethyl-eneamino)benzene-sulfonato-κN,N',O]manganese(II) dihydrate.

The title complex, [Mn(C(12)H(9)N(2)O(3)S)(2)]·2H(2)O, is isotypic with the previously reported Zn(II) and Cd(II) species. The complex was prepared by the reaction of the potassium salt of 2-(2-pyridylmethyl-eneamino)benzene-sulfonic acid with MnCl(2)·6H(2)O in methanol. The complex displays twofold symmetry, with the ligands coordinated in a tridentate meridional-like arrangement through pyridyl N, imine N, and sulfonate O atoms. The metal center has a strongly distorted octa-hedral coordination geometry. The uncoordin-ated water mol-ecules and the complexes participate in a hydrogen-bonding network, forming a two-dimensional structure parallel to the ab plane.

Bis[2-(2-pyridylmethyl-eneamino)benzene-sulfonato]-κN,N',O;κN,N'-copper(II).

In the mononuclear title compound, [Cu(C(12)H(9)N(2)O(3)S)(2)], the copper(II) salt of 2-(2-pyridylmethyl-eneamino)benzene-sulfonic acid, the Cu(II) atom is coordinated by one O and two N atoms from a monoanion as well as by two N atoms from another monoanion in a distorted trigonal-bipyramidal environment.

Bis[2-(2-pyridylmethyl-eneamino)benzene-sulfonato-κN,N',O]cobalt(II) dihydrate.

The title complex, [Co(C(12)H(9)N(2)O(3)S)(2)]·2H(2)O, has site symmetry 2 with the Co(II) cation located on a twofold rotation axis. Two tridentate 2-(2-pyridylmethyl-eneamino)benzene-sulfonate (paba) ligands chelate to the Co(II) cation in a distorted octa-hedral geometry. The pyridine and benzene rings in the paba ligand are oriented at a dihedral angle of 42.86 (13)°. Inter-molecular O-H⋯O and C-H⋯O hydrogen bonding is present in the crystal structure.

Bis[2-(2-pyridylmethyl-eneamino)benzene-sulfonato-κN,N',O]zinc(II) dihydrate.

In the title complex, [Zn(C(12)H(9)N(2)O(3)S)(2)]·2H(2)O, the Zn(II) ion lies on a crystallographic inversion center and is coordinated by four N atoms and two O atoms from two tridentate 2-(2-pyridylmethyl-eneamino)benzene-sulfonate ligands in a slightly distorted octa-hedral environment. In the crystal structure, the complex forms a two-dimensional network through inter-molecular O-H⋯O and C-H⋯O hydrogen bonds.

Bis[2-(2-pyridylmethyl-eneamino)benzene-sulfonato-κN,N',O]cadmium(II) dihydrate.

The title complex, [Cd(Paba)(2)]·2H(2)O or [Cd(C(12)H(9)N(2)O(3)S)(2)]·2H(2)O, was synthesized by the reaction of the potassium salt of 2-(2-pyridylmethyl-eneamino)benzene-sulfonic acid (PabaK) with CdCl(2)·2.5H(2)O in methanol. The Cd(II) atom lies on a crystallographic twofold axis and is coordinated by four N atoms and two O atoms from two deprotonated tridentate 2-(2-pyridylmethyl-eneamino)benzene-sulfonate ligands in a slightly distorted octa-hedral environment. There are extensive hydrogen bonds of the type O-H⋯O between the uncoordinated water molecules and the sulfonate O atoms, through which the complex forms a layered structure parallel to (001).