Ibrahima Elhadj Thiam

Bis(2-{[2-(2-hy­droxy­benzyl­amino)­eth­yl]amino­meth­yl}phenolato-κ3N,N′,O1)cobalt(III) nitrate monohydrate

In the title compound, [Co(C16H19N2O2)2]NO3·H2O, the CoIII ion is located on an inversion center and is six-coordinated by two phenolate O atoms and four amino N atoms from two diamine ligands, forming an octahedral geometry. The water molecule and the nitrate anion are located close to an inversion center, and are thus equally disordered by symmetry. The crystal packing is stabilized by intermolecular O—H⋯O hydrogen bonds involving the uncoordinated water molecule and the free phenol hydroxyl group with the nitrate anion. N—H⋯O hydrogen bonds involving the amino groups and the nitrate anions connect the complex molecules along the c axis.

(S,E)-3-[(2-Hy-droxy-benzyl-idene)amino]-2-(2-hy-droxy-phen-yl)-2,3-dihydro-quinazolin-4(1H)-one.

In the title compound, C21H17N3O3, the dihydroquinazoline ring adopts a screw-boat conformation and its stereogenic C atom has an S configuration. The dihedral angle between the mean planes of the two hydroxyphenyl rings is 86.61 (12)°. The amino H atom forms an intramolecular hydrogen bond with a phenol O atom, while the hydrazine N atom acts as an acceptor for the H atom of the other phenol group. In the crystal, O—H⋯N and O—H⋯O hydrogen bonds and weak C—H⋯centroid(π-ring) intermolecular interactions are observed, forming chains along [1-10] and [110].

Dichlorido{N′-[phen­yl(pyridin-2-yl-κN)methyl­idene]isonicotinohydrazide-κ2N′,O}zinc

The title compound, [ZnCl2(C18H14N4O)], crystallizes with two molecules in the asymmetric unit, which differ in the tautomeric (neutral and zwitterionic) forms of the coordinating organic ligand. In both molecules, the ZnII atom adopts a distorted square–pyramidal geometry by two N and one O atoms of the Schiff base ligand and two Cl atoms acting as monodentate chloride anions. The crystal packing is stabilized by N—H⋯N and N—H⋯Cl hydrogen bonds, forming a two-dimensional network parallel to the ac plane.

Bis{2-amino-2-oxo-N-[(1E)-1-(pyridin-2-yl-κN)ethyl­idene]acetohydrazidato-κ2N′,O1}nickel(II)

In the title compound, [Ni(C9H9N4O2)2], the NiII ion is situated on a twofold rotation axis and is coordinated by two O and four N atoms from two tridentate {2-amino-2-oxo-N-[(1E)-1-(pyridin-2-yl-κN)ethylidene]acetohydrazidate ligands in a distorted octahedral geometry. In the crystal, N—H⋯O and N—H⋯N hydrogen bonds link the molecules into columns in [001]. The porous crystal packing is further stabilized via π–π interactions between the pyridine rings of neighbouring molecules [centroid–centroid distance = 3.746 (3) Å] with voids of 270 Å3.

Dichlorido[2-(pyridin-2-yl)-N-(pyridin-2-yl­methyl­idene)ethanamine-κ3N,N′,N′′]manganese(II) monohydrate

In the title complex, [MnCl2(C13H13N3)]·H2O, the MnII atom is in a distorted square-pyramidal environment, with an Addison τ parameter of 0.037. The coordination geometry is defined by three N-atom donors from the tridentate 2-(pyridin-2-yl)-N-(pyridin-2-ylmethylidene)ethanamine ligand and two terminal Cl atoms. Although the H atoms of the lattice water molecule were not located, O⋯O distances of 3.103 (7) Å and O⋯Cl distances of 3.240 (3) and 3.482 (4) Å suggest that hydrogen bonding is responsible for the stabilization of the crystal packing.

Bis(N,N′-dimethyl­ethylenediammonium) tris­(oxalato-κ2 O 1,O 2)cobaltate(II) dihydrate: an ion-pair complex

The CoII ion in the title complex, (C4H14N2)2[Co(C2O4)3]·2H2O, is coordinated by three oxalate ions, resulting in a distorted octahedral geometry. Two uncoordinated water molecules are present in asymmetric unit. Intermolecular N—H⋯O and O—H⋯O hydrogen bonds between the different entities stabilize the crystal structure.

{2-[(2-Acetyl­hydrazin-1-yl­idene)methyl-κ2N1,O]-6-methoxy­phenolato-κO1}(nitrato-κO)copper(II) monohydrate

In the title complex, [Cu(C10H11N2O3)(NO3)]·H2O, prepared from the Schiff base N′-(3-methoxy-2-oxidobenzylidene)acetohydrazide, the CuII atom is coordinated by two O atoms and one N atom from the ligand and one O atom from a nitrate group in a distorted square-planar geometry. The CuII atom has a weak interaction with another O atom of the nitrate group. The two O atoms of the tridentate Schiff base ligand are in a trans arrangement. O—H⋯O and N—H⋯O hydrogen bonds involving the uncoordinated water molecule are observed.