catena-Poly[[[(acetato-κO,O')cadmium]-µ-acetato-κO,O':O'-µ-{1,2-bis-[4-(pyridin-3-yl)pyrimidin-2-ylsulfan-yl]ethane}-κN,N] trihydrate].

The title compound, {[Cd(CH(3)COO)(2)(C(20)H(16)N(6)S(2))]·3H(2)O}(n), exists as a one-dimensional zigzag polymer in which the Cd(II) ion shows a seven-coordinate [CdO(5)N(2)] distorted penta-gonal-bipyramidal geometry with the N atoms in axial positions and an N-Cd-N angle of 176.94 (13)°. The metal atoms are bridged by 1,2-bis-[4-(pyridin-3-yl)pyrimidin-2-ylsulfan-yl]ethane ligands, giving a polymeric chain extending along the b axis. Adjacent chains related by an inversion center are further bridged by Cd-O bonds formed between the O atom of one of the acetate ligands and the metal atom. The five Cd-O bond lengths are in the range 2.329 (3)-2.485 (3) Å. There are π-π stacking inter-actions between the aromatic rings of adjacent polymeric chains, the centroid-centroid distances being 3.556 (3) and 3.698 (3) Å, organizing the chains into a three-dimensional framework. This framework is additionally stabilized by extensive O-H⋯O and O-H⋯N hydrogen bonding between water mol-ecules and the ligands.

Dinuclear cadmium(II), zinc(II), and manganese(II), trinuclear nickel(II), and pentanuclear copper(II) complexes with novel macrocyclic and acyclic Schiff-base ligands having enantiopure or racemic camphoric diamine components.

Four novel [3 + 3] Schiff-base macrocyclic ligands I-IV condensed from 2,6-diformyl-4-substituted phenols (R = CH(3) or Cl) and enantiopure or racemic camphoric diamines have been synthesized and characterized. Metal-ion complexations of these enantiopure and racemic [3 + 3] macrocyclic ligands with different cadmium(II), zinc(II), manganese(II), nickel(II), and copper(II) salts lead to the cleavage of Schiff-base C horizontal lineN double bonds and subsequent ring contraction of the macrocyclic ligands due to the size effects and the spatial restrictions of the coordination geometry of the central metals, the steric hindrance of ligands, and the counterions used. As a result, five [2 + 2] and one [1 + 2] dinuclear cadmium(II) complexes (1-6), two [2 + 2] dinuclear zinc(II) (7 and 8), and two [2 + 2] dinuclear manganese(II) (9 and 10) complexes together with one [1 + 1] trinuclear nickel(II) complex (11) and one [1 + 2] pentanuclear copper(II) complex (12), bearing enantiopure or racemic ligands, different substituent groups in the phenyl rings, and different anionic ligands (Cl(-), Br(-), OAc(-), and SCN(-)), have been obtained in which the chiral carbon atoms in the camphoric backbones are arranged in different ways (RRSS for the enantiopure ligands in 1, 2, 4, 5, and 7-10 and RSRS for the racemic ligands in 3, 6, 11, and 12). The steric hindrance effects of the methyl group bonded to one of the chiral carbon atoms of camphoric diamine units are believed to play important roles in the formation of the acyclic [1 + 1] trinuclear complex 11 and [1 + 2] dinuclear and pentanuclear complexes 6 and 12. In dinuclear cadmium(II), zinc(II), and manganese(II) complexes 1-10, the sequence of separations between the metal centers is consistent with that of the ionic radii shortened from cadmium(II) to manganese(II) to zinc(II) ions. Furthermore, UV-vis, circular dichroism, (1)H NMR, and fluorescence spectra have been used to characterize and compare the structural differences between related compounds.

Poly[[[diisothio-cyanato-cobalt(II)]-bis-[µ-4-tert-butyl-2,6-bis-(1,2,4-triazol-1-ylmeth-yl)phenol]] dimethyl-formamide disolvate dihydrate].

In the title compound, {[Co(NCS)(2)(C(16)H(20)N(6)O)(2)]·2C(3)H(7)NO·2H(2)O}(n), each Co(II) ion located on an inversion center is six-coordinated by four equatorial N atoms from four different 4-tert-butyl-2,6-bis-(1,2,4-triazol-1-ylmeth-yl)phenol (L) ligands, and by two N atoms from two axial thio-cyanate anions [Co-N = 2.104 (3)-2.144 (3) Å]. The metal centres are connected via the bidentate L ligands into two-dimensional polymeric layers parallel to bc plane. The dimethyl-formamide and solvent water mol-ecules participate in inter-molecular O-H⋯O and O-H⋯S hydrogen bonds, which consolidate the crystal packing.

Diaqua-dibromidobis[3-dimethyl-amino-1-(4-pyridyl-κN)prop-2-en-1-one]cadmium(II).

In the title compound, [CdBr(2)(C(10)H(12)N(2)O)(2)(H(2)O)(2)], the Cd(II) ion is located on an inversion center and is six-coordinated by two N atoms [Cd-N = 2.377 (3) Å] from two different 3-dimethyl-amino-1-(4-pyrid-yl)prop-2-en-1-one ligands, two O atoms [Cd-O = 2.355 (2) Å] from two coordinated water mol-ecules and two bromide anions [Cd-Br = 2.6855 (5) Å]. Inter-molecular O-H⋯O hydrogen bonds link the mol-ecules into layers parallel to the bc plane.

Triaqua-chlorido[3-dimethyl-amino-1-(2-pyrid-yl)prop-2-en-1-one-κN]manganese(II) chloride.

In the title compound, [MnCl(C(10)H(12)N(2)O)(H(2)O)(3)]Cl, the Mn(II) ion has a distorted octa-hedral coordination environment formed by one N and one O atom from the chelating 3-dimethyl-amino-1-(2-pyrid-yl)prop-2-en-1-one ligand, one chloride anion and three coordinated water mol-ecules. Inter-molecular O-H⋯O and O-H⋯Cl hydrogen bonds link the cations and anions into layers parallel to the ac plane.