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Vol 43, No 6 (2017)
- Year: 2017
- Articles: 10
- URL: https://journals.rcsi.science/1070-3284/issue/view/13319
Article
New approach to the synthesis of polynuclear heterometallic pivalates with iron and manganese atoms
Abstract
New hexanuclear Fe(III)–Mn(II, III) pivalates [Fe2III Mn4II(O)2(Piv)10(HPiv)4] (I) or [Fe4III Mn2III(O)2(Piv)12(CH2O2)(HPiv)2] · Et2O (II) are synthesized using the solid-state thermolysis of [Fe2Mn(O)(Piv)6(HPiv)3] (90°С). Complexes I and II differ by the ratio of iron and manganese ions, which depends on the atmospheric composition during thermolysis. The structures of compounds I and II are determined by X-ray diffraction studies. According to the parameters of the Mössbauer spectrum, complex I contains the Fe3+ ions in the high-spin state in the octahedral environment of oxygen atoms.
345-351
Thiocyanates of rare-earth elements with tetramethylphenanthroline
Abstract
Molecular [M(NCS)3(H2O)(Me4Phen)2] · (Me4Phen) · 0.75EtOH and anionic [H(Me4Phen)][М(NCS)4(Me4Phen)2] complexes are synthesized using thiocyanates М(NCS)3 · 6H2O (M = Y, Eu, Tb) and 3,4,7,8-tetramethyl-1,10-phenanthroline (Me4Phen). The complexes are characterized by IR spectroscopy and elemental, X-ray phase, and X-ray diffraction analyses (CIF files CCDC no. 1498178–1498184). The thermoanalytical study shows that the solvate molecules Me4Phen are localized in the internal coordination sphere of the molecular complexes at 195–250°C. The magnetic behavior of the Eu and Tb complexes is governed by the nature of the Ln ion.
352-363
Framework coordination polymer based on the [Re3Mo3S8(CN)6]6–heterometallic cluster anions and Cd2+ cations
Abstract
A new coordination polymer, [Cd(NH3)4]2{Cd[Re3Mo3S8(CN)6]}·1.5H2O (I), was prepared by the reaction between solutions of Cd(CH3COO)2 · 2H2O in aqueous ammonia and CaK4[Re3Mo3S8(CN)6] · 8H2O in water. The crystals are cubic, space group Fm3m (Prussian blue structural type); a = 15.0268(4) Å (CIF file CSD no. 431555). According to ESR data, compound I is paramagnetic, g-factor is 2.298. Thermal stability investigation by TGA and powder X-ray diffraction showed that elimination of coordinated NH3 molecules is accompanied by sample amorphization.
364-367
Zn-containing double complex salts formed by Keggin type polyoxotungstates: Synthesis and crystal structure
Abstract
Novel double complex salts, [Zn(DMF)6]2[SiW12O40] · 2H2O (I) and [Zn(H2O)2(DMF)4][Zn(DMF)6]2[PW12O40]2 · 6DMF (II) (DMF = N,N-dimethylformamide), were prepared by the reaction of Zn2+ and heteropoly acids Hx[EW12O40] · xH2O (E = P, X = 3, E = Si, X = 4) in DMF. Compounds I and II were studied by X-ray diffraction (СIF files CCDC nos. 1497570 (I) and 1497571 (II)) and IR spectroscopy.
368-372
Synthesis and structure of bis-hexaaquasodium bis-nitrilotris(methylenephosphonato)decaaquamonohydrohexasodiumlanthanate trihydrate [Na(H2O)6]2[LaNa6H(H2O)10{N(CH2PO3)3}2] · 3H2O
Abstract
A complex salt of nitrilotris(methylenephosphonic acid) with sodium and lanthanum was prepared, isolated, and studied. The salt [Na(H2O)6]2[LaNa6H(H2O)10{N(CH2PO3)3}2] · 3H2O crystallizes in space group P21/c, Z = 2, a = 11.86630(10), b = 10.55060(10), c = 19.99270(10) Å, β = 94.6760°. The La coordination polyhedron is a virtually regular rhombohedron. The Na atom is coordinated at the vertices of a distorted octahedron. Both ligand molecules chelate the La atom; each PO3 group forms a La–O–P–O–Na bridge; the ligand denticity is 7.
373-379
Synthesis, structure, and fungicidal activity of mono- and binuclear mixed-ligand copper complex with p-nitrobenzoic acid and monoethanolamine
Abstract
Mixed-ligand metal complexes based on ethanolamines and simple monosubstituted benzoic acids, in particular, mono- and binuclear copper complexes with monoethanolamine (MEA) and p-nitrobenzoic acid (PNBA), [Cu2+((PNBA)2-(MEA)2)] (I) and [2Cu2+((PNBA)4-(MEA)2(H2O)2)] (II), were prepared for the first time. The structures of the complexes were characterized by FT IR spectroscopy and X-ray diffraction (CIF files CCDC no. 1497849 (I) and no. 1497848 (II)). The doubly charged copper ions are coordinated at the vertices of octahedra, which are highly distorted due to the Jahn–Teller effect. In the crystals of the mononuclear complex I, the molecules are joined into columns, whereas in the binuclear compound II, a three-dimensional framework is formed owing to intermolecular H-bonds involving the nitro group. Fungicidal activities were found for compounds I, II, MEA, PNBA, previously obtained single-ligand copper complexes with MEA and PNBA, and MEA- and PNBA-based organic salt. The biological activity gradually increases in the series: ligand, single-ligand metal complex, organic salt, mono- and binuclear mixed-ligand complex, i.e., some ligands and copper ions show a synergistic effect.
380-388
Synthesis, crystal structures, and catalytic property of dioxomolybdenum(VI) complexes with hydrazone ligands derived from 3,5-Di-tert-butylsalicylaldehyde
Abstract
Two new dioxomolybdenum(VI) complexes, [MoO2L1(MeOH)] (I) and [MoO2L2] (II), where L1 and L2 are the anionic forms of N'-(2-hydroxy-3,5-di-tert-butylbenzylidene)-4-methoxybenzohydrazide and 2-amino-N'-(2-hydroxy-3,5-di-tert-butylbenzylidene)benzohydrazide, respectively, have been synthesized and characterized by elemental analysis, FT-IR spectra, and single crystal X-ray determination (CF files CCDC nos. 1448089 (I), 1487063 (II)). The crystal of I is monoclinic: space group P21/n, a = 7.353(1), b = 24.758(3), c = 13.891(2) Å, β = 101.013(2)°, V = 2482.3(6) Å3, Z = 4, R1 = 0.0848, wR2 = 0.2050. The crystal of II is monoclinic: space group P21/c, a = 6.752(1), b = 16.947(1), c = 19.510(1) Å, β = 96.891(2)°, V = 2216.5(4) Å3, Z = 4, R1 = 0.0670, wR2 = 0.1638. The Mo atom in complex I is in octahedral coordination, with three donor atoms of the hydrazone ligand, two oxo groups, and one methanol O atom. The Mo atom in complex II is in square pyramidal coordination, with three donor atoms of the hydrazone ligand, and two oxo groups. The complexes have interesting catalytic properties for sulfoxidation reactions.
389-395
Synthesis, characterization, crystal structures, and antibacterial activity of oxidovanadium(V) complexes with mixed ligands
Abstract
Two new oxidovanadium(V) complexes, [VO(L)(Ehp)] (I) and [VO(L)(Aha)] (II), where L is the dianionic form of 4-bromo-N'-(4-oxopentan-2-ylidene)benzohydrazide (H2L), Ehp is the monoanionic form of 2-ethyl-3-hydroxy-4H-pyran-4-one (HEhp), and Aha is the monoanionic form of acetohydroxamic acid (HAha), were prepared and characterized by elemental analysis, infrared and electronic spectra, and 1H NMR spectra. Structures of the complexes were further confirmed by single crystal X-ray diffraction (CIF files CCDC nos. 1477847 (I), 1477850 (II)). H2L coordinates to the V atom through the two enolic O atoms and the imino N atom. The ligands Ehp and Aha coordinate to the V atoms through bidentate OO donor set. The V atoms of the complexes are in octahedral coordination, with the oxo group furnished the octahedral geometry. The complexes show effective antibacterial activity against Bacillus subtilis.
396-403
Synthesis, crystal structures, and catalytic properties of two oxidovanadium(V) complexes with tridentate Schiff bases
Abstract
Two new oxidovanadium(V) complexes, [VO2L1] (I) and [VO2L2] (II), where L1 and L2 are the deprotonated forms of 4-methyl-2-[(2-morpholin-4-ylethylimino)methyl]phenol (HL1) and 2-[(2-isopropylaminoethylimino) methyl]-4-trifluoromethoxyphenol (HL2), respectively, have been prepared and characterized by physico chemical methods and single crystal X-ray diffraction (CIF files CCDC nos. 1443671 (I), 1443672 (II)). The V atom in each complex is coordinated by the phenolate oxygen, imino nitrogen and amino nitrogen of the Schiff base ligand, and two oxo groups, forming trigonal-bipyramidal geometry. The oxidation of olefins with the complexes as catalyst was evaluated, which indicated that both complexes showed effective catalytic efficiency in oxidation of several aliphatic and aromatic substrates by using tert-butyl hydrogen peroxide as oxidant.
404-410
Synthesis, characterization, and crystal structures of dioxomolybdenum(VI) complexes with O,N,N type tridentate hydrazone ligands as catalyst for oxidation of olefins
Abstract
The preparation of Mo(VI) hydrazone complexes, cis-[MoO2L1(CH3OH)] (I) and cis-[MoO2L2(CH3OH)] (II), derived from N'-(3-bromo-2-hydroxybenzylidene)-2-chlorobenzohydrazide (H2L1) and N'-(3-bromo-2-hydroxybenzylidene)-4-bromobenzohydrazide (H2L2), respectively, is reported. The complexes were characterized by elemental analyses, infrared and electronic spectroscopy, and single crystal structure analysis (CIF files ССDС nos. 1426875 (I), 1426871 (II)). The Mo atoms are coordinated by two cis terminal oxygen, ONO from the hydrazone ligand, and methanol oxygen. Even though the hydrazone ligands and the coordination sphere in both complexes are similar, the unit cell dimensions and the space groups are different. Complex I crystallized as orthorhombic space group Pca21 with unit cell dimensions a = 27.887(2), b = 8.0137(7), c = 15.544(1) Å, V = 3473.8(5) Å3, Z = 8, R1 = 0.0450, wR2 = 0.0539. Complex II crystallized as triclinic space group P1, with unit cell dimensions a = 8.2124(4), b = 8.5807(5), c = 12.9845(8) Å, α = 83.366(2)°, β = 79.201(2)°, γ = 80.482(2)°, V = 883.03(9) Å3, Z = 2, R1 = 0.0278, wR2 = 0.0569. The complexes were tested as catalyst for the oxidation of olefins, and showed effective activity.
411-419