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Том 43, № 3 (2017)
- Год: 2017
- Статей: 7
- URL: https://bakhtiniada.ru/1070-3284/issue/view/13311
Article
Quantum-chemical DFT model for the formation of the MN2O2, MN2O2X, or MN2O2X2 (X = S, Se) coordination mode in the bis(ligand) Ni(II), Zn(II), and Cd(II) azomethine complexes
Аннотация
The molecular structures and relative energies of tetra-, penta-, and hexacoordinated stereoisomers of the bis(ligand) complexes ML2 (M = Ni(II), Zn(II), Cd(II)) with bi- and tridentate heterocyclic azomethine derivatives (coordination modes MN2O2, MN2O2X, or MN2O2X2 (X = S, Se)) are calculated using the density functional theory. The dependences of the relative stabilities of the stereoisomers of the complexes with the coordination numbers 4, 5, and 6 on the electronic configuration of the central metal atom and structural features of the ligands are established.
139-146
Syntheses, structures, and phosphorescence of complexes (A)[Gd(L)4] and [Gd(Phen)(L)3] (L = iso-Bu2PS2-, C4H8NCS2-; A = NH4+, Et4N+)
Аннотация
Complexes (A)[Gd(L)4] and [Gd(Phen)(L)3] (L = iso-Bu2PS2-, C4H8NCS2-; A = NH4+, Et4N+) are synthesized. The crystal structure of compound [Gd(Phen)(iso-Bu2PS2)3] · MeCN is determined by X-ray diffraction analysis (CIF file CCDC no. 1455418). The structure consists of molecules of the mononuclear complex [Gd(Phen)(iso-Bu2PS2)3] and MeCN. The coordination polyhedron N2S6 of the Gd atom is a distorted antiprism. The complexes exhibit phosphorescence in a range of 400–600 nm. The energies of the triplet levels of the ligands C4H8NCS2-(23336 cm–1) and iso-Bu2PS2-(23506 cm–1) are determined from the phosphorescence spectra of complexes (A)[Gd(L)4] in frozen ethanol (77 K).
147-155
Electrochemical synthesis, properties, and structure of copper, nickel, and cobalt complexes of tridentate tosylamino-functionalized mercaptopyrazole Schiff base
Аннотация
Copper, nickel, and cobalt complexes of the N,N,S-tridentate tosylamino-functionalized mercaptopyrazole Schiff base were obtained by an electrochemical method. The structure and composition of the metal chelates were characterized by C, H, N elemental analysis data and IR and 1H NMR spectroscopy. More data on the structures of the complexes were obtained by magnetochemical and X-ray absorption spectroscopy measurements. The mononuclear structure of the copper(II) complex was confirmed by X-ray diffraction (CIF file CCDC no. 1473320).
156-163
Synthesis, crystal structure, and biological properties of the complex [Co(DmgH)2(Seu)1.4(Se-Seu)0.5(Se2)0.1][BF4]
Аннотация
A new Co(III) dioxime complex with selenocarbamide was obtained by the reaction of Co(BF4)2 ∙ 6H2O, DmgH2, and Seu (DmgH2 = dimethylglyoxime, Seu = selenocarbamide). According to X-ray diffraction (CIF file CCDC no. 1485732), the product was an ionic coordination compound with unusual composition, [Co(DmgH)2(Seu)1.4(Se-Seu)0.5(Se2)0.1][BF4] (I). Apart from two monodeprotonated DmgH‾ molecules, the central atom coordinates neutral Seu, Se-Seu, and Se2 molecules. Thus, the crystal contains the complex cations [Co(DmgH)2(Seu)2]+, [Co(DmgH)2(Seu)(Se-Seu)]+, and [Co(DmgH)2(Seu)(Se2)]+. Each [BF4]‾ anion is linked to the cations not only by electrostatic forces but also by intermolecular N–H···F hydrogen bonds (H-bonds). The complex cations are combined by intermolecular N–H···O H-bonds. The new coordination compound was found to possess biological activity. Treatment of the garlic (Allium sativum L.) foliage with an aqueous solution of I optimizes the content of selenium in the leaves and cloves and enhances the growth and plant productivity. The organs of treated plants are characterized by enhanced antioxidant protection owing to increasing activity of antioxidant enzymes and contents of proline and assimilation pigments, and decreasing lipid peroxidation.
164-171
Tosylate cluster complexes (Bu4N)2[М6I8(O3SC6H4CH3)6] (M = Mo, W)
Аннотация
The reaction of (Bu4N)2[М6I14] with silver p-toluenesulfonate (tosylate) AgO3SC6H4CH3 affords iodide cluster complexes (Bu4N)2[М6I8(Рts)6] (М = Mo (I), W (II); Рts is tosylate anion CH3C6H4SO3). According to the X-ray diffraction data (СIF file CCDC no. 1027969), the molybdenum atoms in (Bu4N)2[Мo6I8(Рts)6] · 2Et2O · 2MeCN (I′) are coordinated via the monodentate mode by the tosylate ligands. The 1H NMR and mass spectrometry data show that in donor solvents the complexes undergo solvolysis followed by the substitution of the tosylate ligands by the solvent molecules, which is accompanied by changes in the electrochemical properties, as shown by the cyclic voltammetry data.
172-180
Synthesis, crystal structures, and antibacterial activity of copper(II) and cobalt(III) complexes derived from 2-[(2-dimethylaminoethylimino)methyl]-4-methylphenol
Аннотация
A new tetranuclear copper(II) complex (I) and a new mononuclear cobalt(III) complex (II) have been synthesized from the Schiff base compound 2-[(2-dimethylaminoethylimino)methyl]-4-methylphenol. The complexes have been characterized by physico-chemical and spectroscopic methods, as well as single crystal X-ray determination (CIF files CCDC nos. 1447778 (I) and 1447779 (II)). The Cu atoms in complex I are in square pyramidal coordination, and the Co atom in complex II is in octahedral coordination. Crystal structures of the complex are stabilized by hydrogen bonds and π···π interactions. The complexes and the Schiff base compound were assayed for antibacterial activities against three Gram-positive bacterial strains (B. subtilis, S. aureus, and St. faecalis) and three Gram-negative bacterial strains (E. coli, P. aeruginosa, and E. cloacae) by MTT method. As a result, the complexes showed effective antimicrobial activity against the microorganisms tested.
181-188
Synthesis, crystal structures, and catalytic oxidation of olefins of dioxomolybdenum(VI) complexes with aroylhydrazone ligands
Аннотация
Two Mo(VI) aroylhydrazone complexes, cis-[MoO2(L1)(CH3OH)] (I) and cis-[MoO2(L2)(CH3OH)] (II), derived from 2-bromo-N'-(3,5-dibromo-2-hydroxybenzylidene)benzohydrazide (H2L1) and 2-bromo-N'-(2-hydroxy-4-methoxybenzylidene)benzohydrazide (H2L2), respectively, are reported. The complexes were characterized by elemental analyses, infrared and electronic spectroscopy, and single crystal structure analysis (CIF files CCDC nos. 1443679 (I) and 1443678 (II)). The Mo atoms are coordinated by two cis terminal oxygen, ONO from the aroylhydrazone ligand, and methanol oxygen. Complex I crystallized as monoclinic space group P21/c with unit cell dimensions a = 8.075(2), b = 13.905(1), c = 16.448(1) Å, β = 91.282(2)°, V = 1846.5(4) Å3, Z = 4, R1 = 0.0859, wR2 = 0.2066. Complex II crystallized as triclinic space group P\(\overline 1 \), with unit cell dimensions a = 8.0824(6), b = 10.5919(8), c = 10.7697(8), α = 96.432(2)°, β = 97.438(2)°, γ = 103.119(2)°, V = 880.8(1) Å3, Z = 2, R1 = 0.0271, wR2 = 0.0571. The complexes were tested as catalyst for the oxidation of olefins and showed effective activity.
189-195