Hexa­kis­(dimethyl­formamide-κO)manganese(II) (dimethyl­formamide-κO)pentakis(­thio­cyanato­-κN)chromate(III)

The title compound, [Mn(C3H7NO)6][Cr(NCS)5(C3H7NO)], was obtained unintentionally as a product of an attempted synthesis of heterometallic complexes based on Reineckes anion using manganese powder, Reineckes salt and 1-(2-hy­droxy­eth­yl)tetra­zole as starting materials. The crystal structure of the complex consists of an [Mn(dmf)6]2+ cation and a [Cr(NCS)5(dmf)]2− anion (dmf = dimethyl­formamide). The MnII and CrIII atoms show a slightly distorted octa­hedral MnO6 and CrN5O coordination geometries with adjacent angles in the range 85.29 (13)–95.96 (14)°

Aromaticity in heterocyclic analogues of benzene : comprehensive analysis of structural aspects, electron delocalization and magnetic characteristics

The degree of aromaticity of six-membered monoheterocycles with IV-VI group heteroatoms (C(6)H(5)X, where X = SiH, GeH, N, P, As, O(+), S(+), Se(+)) was analyzed using the results of ab initio calculations at the MP2/cc-pvtz level. Values of common aromaticity indices including those based on electronic delocalization properties, structural-dynamic features and magnetic properties all indicate high aromaticity of all considered heterocycles. A decrease in aromaticity is observed with increasing atomic number of the heteroatom, except in the case of the pyrylium cation. However, not all types of indices or even different indices within the same type correlate well among each other. Ring currents have been obtained at the HF/cc-pvdz level using the ipsocentric formulation. Ring current maps indicate that in the case of cationic heterocycles the ring current persists in all molecules under consideration. The different conclusions reached depending on the type of index used are a manifestation of the fact that when not dealing with hydrocarbons, aromaticity is ill-defined. One should always express explicitly which property of the molecules is considered to establish a degree of "aromaticity"

Tris(2,2′-bipyridine-κ2 N,N′)cobalt(III) tris­(oxalato-κ2 O 1,O 2)ferrate(III) mono­hydrate

The title compound, [Co(C10H8N2)3][Fe(C2O4)3]·H2O, con­sists of two discrete tris­(chelate) metal ions (CoIIIN6 and FeIIIO6 chromophores) and a water mol­ecule. The structure is highly symmetrical; the CoIII and FeIII ions occupy positions with site symmetry 3.2. The coordination polyhedra of the metal atoms have a nearly octa­hedral geometry with noticeable trigonal distortions. The Co—N and Fe—O bond lengths are equal by symmetry, viz. 1.981 (2) and 1.998 (4) Å, respectively. The cations and anions are arranged alternately along their threefold rotation axes parallel to [001], forming chains that are packed in a hexa­gonal manner. The water mol­ecules occupy voids between the chains. The crystal under investigation was an inversion twin

Hexa­kis­(dimethyl­formamide-κO)manganese(II) μ-oxido-bis­[trichlorido­ferrate(III)]

The title compound, [Mn(C3H7NO)6][Fe2Cl6O], was obtained unintentionally as a product of an attempted synthesis of heterometallic complexes with Schiff base ligands using manganese powder and FeCl3·6H2O as starting materials. In the [Fe2OCl6]2− anion, the O atom and the Fe atom occupy positions with site symmetry and 3, respectively, resulting in a linear Fe—O—Fe angle and a staggered conformation. The octa­hedrally surrounded cation (site symmetry ) and the [Fe2Cl6O]2− anion are alternately stacked along [001]

Crystal structure of tetrakis[μ2-2-(dimethylamino)ethanolato-κ3N,O:O]di-μ3-hydroxido-dithiocyanato-κ2N-dichromium(III)dilead(II) dithiocyanate acetonitrile monosolvate

The tetranuclear complex cation of the title compound, [Cr2Pb2(NCS)2(OH)2(C4H10NO)4](SCN)2·CH3CN, lies on an inversion centre. The main structural feature of the cation is a distorted seco-norcubane Pb2Cr2O6 cage with a central four-membered Cr2O2 ring. The CrIII ion is coordinated in a distorted octahedron, which involves two N atoms of one bidentate ligand and one thiocyanate anion, two μ2-O atoms of 2-(dimethylamino)ethanolate ligands and two μ3-O atoms of hydroxide ions. The coordination geometry of the PbII ion is a distorted disphenoid, which involves one N atom, two μ2-O atoms and one μ3-O atom. In addition, weak Pb...S interactions involving the coordinating and non-coordinating thiocyanate anions are observed. In the crystal, the complex cations are linked through the thiocyanate anions via the Pb...S interactions and O—H...N hydrogen bonds into chains along the c axis. The chains are further linked together via S...S contacts. The contribution of the disordered solvent acetonitrile molecule was removed with the SQUEEZE [Spek (2015). Acta Cryst. C71, 9–18] procedure in PLATON. The solvent is included in the reported molecular formula, weight and density

Crystal structure of bis(μ-N-hydroxypicolinamidato)bis[bis(N-hydroxypicolinamide)sodium]

The title compound, [Na2(C6H5N2O2)2(C6H6N2O2)4], is a centrosymmetric coordination dimer based on the sodium(I) salt of N-hydroxypicolinamide. The molecule has an {Na2O6(μ-O)2} core with two bridging carbonyl O atoms and two hydroxamate O atoms of two mono-deprotonated residues of N-hydroxypicolinamide, while two neutral N-hydroxypicolinamide molecules are coordinated in a monodentate manner to each sodium ion via the carbonyl O atoms [the Na—O distances range from 2.3044 (2) to 2.3716 (2) Å]. The pentacoordinated sodium ion exhibits a distorted trigonal–pyramidal coordination polyhedron. In the crystal, the coordination dimers are linked into chains along the c axis via N—H...O and N—H...N hydrogen bonds; the chains are linked into a two-dimensional framework parallel to (100) via weak C—H...O and π–π stacking interactions

Crystal structure of {2-[({2-[(2-aminoethyl)amino]ethyl}imino)methyl]phenolato}aquacopper(II) bromide

In the mononuclear copper(II) title complex, [Cu(C11H16N3O)(H2O)]Br, the CuII atom is coordinated by one O and three N atoms of the Schiff base ligand that forms together with one water molecule a slightly distorted [CuN3O2] square-pyramidal polyhedron. The deviation of the CuII atom from the mean equatorial plane is 0.182 (2) Å. The equatorial plane is nearly coplanar to the aromatic ring of the ligand [angle between planes = 10.4 (1)°], and the water molecule is situated in the apical site. All coordinating atoms (except the imine nitrogen) and the bromide ion contribute to the formation of the N—H...Br, O—H...Br and O—H...O hydrogen bonds, which link molecules into chains along [01-1]

Bis(2-hydroxyiminomethyl-6-methoxyphenolato-κ2N,O1)copper(II)

In the title compound, [Cu(C8H8NO3)2], the nearly planar molecule (r.m.s. deviation = 0.037 Å) is centrosymmetric with the CuII atom lying on an inversion center. The CuII atom is tetracoordinated, displaying a slightly distorted square-planar geometry. The main deviation from the ideal geometry is seen in the differences in the Cu—O [1.8833 (10) Å] and Cu—N [1.9405 (13) Å] bond lengths, while angular deviations are less than 3°. Intramolecular O—H...O and intermolecular Csp2—H...O hydrogen bonds form S(5) and R22(8) ring motifs, respectively. The latter interaction results in chains of molecules along [100]