Synthesis and crystal structure of the [Co<Subscript>2</Subscript>(Nicotinamide)<Subscript>4</Subscript>(C<Subscript>4</Subscript>H<Subscript>9</Subscript>COO)<Subscript>4</Subscript>(H<Subscript>2</Subscript>O)] complex

The [Co₂ L ₄(C₄H₉COO)₄(H₂O)] coordination compound of cobalt(II) valerate with nicotinamide (L) is synthesized and studied by IR spectroscopy. The crystal structure of the synthesized compound is determined. The crystals are triclinic, and the unit cell parameters are as follows: a = 10.2759(10) Å, b = 16.3858(10) Å, c = 16.4262(10) Å, α = 100.538(10)°, β = 101.199(10)°, γ = 90.813 (10)°, Z = 2, and space group P \(\bar 1\). The structural units of the crystal are dimeric molecular complexes in which pairs of cobalt atoms are linked by triple bridges formed by oxygen atoms of two bidentately coordinated valerate anions and a water molecule. The octahedral coordination of each cobalt atom is complemented by the pyridine nitrogen atoms of two nicotinamide ligands and the oxygen atom of the monodentate valerate group. The hydrocarbon chains of the valerate anions are disordered over two or three positions each.     

Aminonitrile rearrangement of s-triazolo[1,5-c]pyrimidines upon reaction with aryl (alkyl) halides

Aminonitrile cleavage of the cyclic system was observed in the reaction of s-triazolo[1,5-c]pyrimidine derivatives with aryl (alkyl) halides in an alkaline medium or in dimethylfonnamide. It is shown that this transformation proceeds through the formation of intermediate quaternary salts. The effect of electron-acceptor and electron-donor substituents on their stability was ascertained. The structures of the substances were established by means of IR, UV, PMR, and mass spectroscopy.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 421–425, March, 1985.     

Interaction of Manganese(II) with Diphenylthiocarbazide. Structure Refinement for Diphenylthiocarbazide and Dehydrodithizone

The interaction of manganese(II) with diphenylthiocarbazide in ethanol solutions with various concentrations has been investigated. The structure and composition of the products have been determined. Structure refinement was performed for diphenylcarbazide and dehydrodithizone.     

Catalytic Activity of 3d-Metal Coordination Compounds with Diphenylthiocarbazide

The catalytic activity of Cr(III), Mn(II), Fe(III), Co(II), Ni(II), and Cu(II) diphenylthiocarbazide complexes in decomposition of hydrogen peroxide was studied. The activation energies of this reaction were correlated with the strength of ligand bonding to the metal atom in the catalyst molecule.     

3d-Metal Nitroprusside–Thiosemicarbazide Complexes: Synthesis and Properties

The following complexes were synthesized from 3d-metal nitroprussides and thiosemicarbazide: [CrL₃][Fe(CN)₅H₂O] · 6H₂O, [FeL₃]₂[Fe(CN)₅NO]₃ · 14H₂O, [CoL₃]₂[Fe(CN)₅NO]₃ · 4H₂O, [NiL₂][Fe(CN)₅NO], [CuL₂][Fe(CN)₅NO] · 5H₂O, and [[ZnL₂][Fe(CN)₅NO], where L is thiosemicarbazide. Their structures and properties were studied by IR and diffuse reflection spectroscopies and DTA.     

Solid State Conductivity and Catalytic Activity of Hexacyanoferrate(II)–Thiosemicarbazide Complexes of 3d-Metals

The temperature dependence of the resistivity of tablets of hexacyanoferrate(II)–thiosemicarbazide complexes of chromium(III), manganese(II), iron(III), cobalt(III), nickel(II), copper(II), and zinc(II) was measured in the range 20-90 °C. A relationship between the conductivity of a substance and the rate constant for the catalytic decomposition of hydrogen peroxide is established.     

Synthesis,IR-spectroscopic study and crystal structure of tris(benzohydrazide)nickel(II) dichloride dihydrate [Ni(L)<Subscript>3</Subscript>]Cl<Subscript>2</Subscript> · 2H<Subscript>2</Subscript>O

Coordination compound [Ni(L)₃]Cl₂ · 2H₂O (L is benzohydrazide) has been synthesized and studied by IR spectroscopy and X-ray diffraction analysis. According to X-ray diffraction, one of the Cl^– ions is disordered over two nonequivalent positions. The crystals are monoclinic, a = 15.423(3) Å, b = 9.697(2) Å, c = 18.893(4) Å, ß = 105.99(3)°, space group P2₁/c, Z = 4. The structural units of the crystal are complex cations [Ni(L)3]2+, in which ligands L are coordinated to the central atom bidentately chelating the metal atoms through the O and N atoms of the hydrazide moiety (Ni–O 2.036(4), 2.051(5), 2.047(5); Ni–N 2.095(5), 2.089(6), 2.097(6) Å). The structural units of the crystal are joined together by cation–anion electrostatic interactions and hydrogen bonds, which involve both H₂O molecules, both Cl^– anions and the N atoms of chelate rings of the complex cation.     

Synthesis, crystal and molecular structure of tetraaquabis(nicotinamide)cobalt(II) phthalate dihydrate

The coordination compound of cobalt(II) with nicotinamide [CoL₂(H₂O)₄][C₆H₄(COO)₂] · 2H₂O (I) (where L stands for nicotinamide) was synthesized and characterized by IR spectroscopy, conductometry, and thermogravimetry. The X-ray structure of complex I was determined. Crystals are monoclinic: a = 15.630(2) ?, b = 7.550(2) ?, c = 21.035(4) ?, β = 100.90(5)°, V = 2437.4(4) ?³, Z = 4, space group C2/c. The structural units of complex I are centrosymmetrical cations [CoL₂(H₂O)₄]²⁺, anions [C₆H₄(COO)₂]²⁻ (lying on axis 2), and molecules of waster of crystallization. Complex cations are packed into layers are alternate with layers containing anions and free H₂O molecules. This is a classical case of π-π-staking interactions that lead to the formation of supramolecular layered assemblies. Original Russian Text ? A.S. Antsyshkina, G.G. Sadikov, T.V. Koksharova, I.S. Gritsenko, V.S. Sergienko, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 8, pp. 1379–1384.     

Synthesis and study of the structure of some pyridazino[4,5-b]quinoxaline derivatives

The structures of 1-oxo-4-hydroxypyridazino[4,5-b]quinoxaline and some of its methyl derivatives were established by IR and UV spectroscopy.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 556–561, April, 1973.