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Vol 45, No 11 (2019)
- Year: 2019
- Articles: 12
- URL: https://bakhtiniada.ru/1070-3284/issue/view/13374
Article
Inner- and Outer-Sphere Coordination of Acido and Neutral N,O-Donor Ligands in the Rare-Earth Metal Complexes
Abstract
The data on the rare-earth metal complexes with the anionic (halides, NCS) and neutral N,O-donor ligands are systematized and generalized. The influence of the ionic radius of the complexing agent and the ligand nature (donor characteristics, steric features, nonvalent interactions) on the formation of the coordination sphere with the inner- or outer-sphere position of the ligands is monitored. The transitions of the ligands from the outer-sphere position to the first coordination sphere are considered.
749-758
New Heterometallic Co(III) Pivalate Complexes with 1,3-(CH2)3(NH2)2
Abstract
The reactions of the complex [Co(DAP)2(Piv)2] · Piv (Ia), where Piv is the pivalate anion, DAP is 1,3-diaminopropane, with Cd(II) and Li(I) pivalates afford heterometallic compounds, molecular complex [CdCo(DAP)2(Piv)5] (I) and polymeric complex [LiCo(DAP)2(Piv)4]n (II) (CIF files CCDC nos. 1908223 and 1908224, respectively). According to X-ray photoelectron spectroscopy, the electronic structure of cobalt ions in complexes Ia and I corresponds to low-spin Co(III) surrounded by strong-field ligands. The thermal destruction of I and II, studied by synchronous thermal analysis, includes stages of desorption of solvate molecules, destruction of the 1,3-diaminopropane molecule with nitrogen evolution, and degradation of carboxylate anions. The final product of thermolysis of I is the complex oxide CdCoO2.
759-766
Intramolecular Nonvalent Interactions in the \({\text{Eu}}_{{\text{2}}}^{{{\text{II}}}}\)EuIII(μ-ORF)2(μ2-ORF)3(μ3-ORF)2(DME)2 Complex
Abstract
A quantum chemical study of fluorinated europium alcoholate \({\text{Eu}}_{{\text{2}}}^{{{\text{II}}}}\)EuIII(μ-ORF)2(μ2-ORF)3(μ3-ORF)2(DME)2 (I), where DME is 1,2-dimethoxyethane, is performed. The structure of the complex contains numerous F⋅⋅⋅F, F⋅⋅⋅O, F⋅⋅⋅H, and C–F → Eu interactions. The nature and energy of these nonvalent interactions is studied in the framework of R. Bader’s quantum theory “Atoms in Molecules.” Nonvalent interactions between the negatively charged fluorine atoms in the structure of complex I can occur due to the donation of the electron density from the regions where the electron density is fairly highly concentrated to the regions of its relative depletion. Weaker C–F → Eu interactions are observed by the additional study using the Topos Pro structural topological program package. These interactions are confirmed by the study of the delocalization indices of electrons in the region of potential Eu⋅⋅⋅F interactions.
767-775
Binuclear Oxidovanadium(IV) Complex with the Bridging Chloranilate Ligand: Synthesis and Magnetic Properties
Abstract
The binuclear oxidovanadium(IV) complex [VO(Dbbpy)Cl(Ca)Cl(Dbbpy)VO] (I) is synthesized by the reaction of [VO(Dbbpy)(H2O)Cl2] (Dbbpy is 4,4'-di-tert-butyl-2,2'-bipyridyl) with chloranilic acid H2Ca in acetonitrile in the presence of Et3N in a yield of 79%. Complex I is reduced at Е1/2 = –842 mV (vs. Ag/AgCl), which is shown by cyclic voltammetry for a solid sample using the paste electrode. The EPR spectra and magnetochemical measurements for complex I confirm the existence of two paramagnetic vanadium(IV) centers with the total spin S = 1 and the antiferromagnetic character of the exchange interaction between the centers.
776-781
Cyclometallated Ni(II) and Pd(II) Complexes of the Azomethine Compounds: Synthesis and Structures
Abstract
New Ni(II) and Pd(II) complexes (Ia and Ib) are synthesized on the basis of the azomethine compound 2-[(E)-[4-methyl-2-[(Z)-p-tolylazo]phenyl]iminomethyl]phenol. The structures and properties of the complexes are characterized by IR spectroscopy, 1Н NMR spectroscopy, and X-ray diffraction analysis (СIF files CCDC nos. 1899223 (Ia) and 1899224 (Ib)). The complex formation affords cyclometallated chelates. According to the X-ray diffraction data, the crystals of the Ni(II) and Pd(II) complexes are isostructural with the square geometry of the coordination mode (MCN2O, M = Ni, Pd) and formation of two five-membered and one six-membered metallocycles.
782-787
Halogen and Hydrogen Bonds in Co-crystalline Ferrocenium Organotellurium Halide Salts
Abstract
The reactions of ferrocene and decamethylferrocene with vinyltellurium trichloride Ph(Cl)C= C(Ph)TeCl3 afford unusual co-crystalline salts [Cp2Fe]+Cl–Ph(Cl)C=C(Ph)TeCl2OH (I) and [(C5Me5)2Fe]+Cl–(Ph(Cl)C=C(Ph)TeCl2OH) (II). The Ph(Cl)C=C(Ph)TeCl2OH molecule in these salts is neutral and forms only non-covalent (hydrogen and chalcogen) bonds with the chloride ion. The hydrolytic replacement of a chlorine atom not involved in the three-center four-electron Cl–Te–Cl bond in Ph(Cl)C=C(Ph)TeCl3 is due to the general moisture sensitivity of organic telluriium halides, and the accompanying oxidation of ferrocene is not a necessary condition for the formation of Ph(Cl)C=C(Ph)TeCl2OH (III). (CCDC nos. 1908530 (I), 1908531 (II), 1908532 (III).)
788-794
Spacer-Armed Copper(II) Complex Based on Bis(2-pyidyl-1,2,4-triazol-3-yl)butane and 1-Aminoethane-1,1-Diphosphonic Acid
Abstract
The new complex [Cu4L2(H2AEDP)2(H2O)4] · 34H2O was prepared by the reaction of CuSO4 with bis(2-pyridyl-1,2,4-triazol-3-yl)butane (H2L) and 1-aminoethane-1,1-diphosphonic acid (H4AEDP) and studied by X-ray diffraction (CIF file CCDC no. 1913117). The complex is a spacer-armed dimer in which two dimer subunits formed with participation of diphosphonate dianions are linked to each other via two doubly deprotonated bis(pyridyl)triazoles. The bridging diphosphonate anion exists in the zwitter ion form, bis(triazolyl)butane is coordinated via the nitrogen atoms of the pyridyl moiety and the deprotonated triazole ring. Analysis of the ESR spectrum of the polycrystalline sample attests to weak exchange interactions in the dimeric moieties.
795-798
Lanthanide Complexes Based on 1,3-Dimethylimidazolium-4-Carboxylate: Syntheses and Structures
Abstract
The reactions of the norzoanemonine zwitterion, 1,3-dimethylimidazolium-4-carboxylate (L), with praseodymium(III), samarium(III), and europium(III) chlorides afford crystals of two types: the isostructural binuclear complexes [Ln2(μ-C6H8N2O2)4(HOCH3)4(H2O)4]Cl6 (Ln = Pr(III) (I) and Eu(III) (II)) and the dimeric samarium complex [Sm2(μ-C6H8N2O2)4(C6H8N2O2)2(H2O)5(OCH3)]Cl5 (III), which are characterized by X-ray diffraction analysis and IR spectroscopy. In complexes I–III (CIF files CCDC nos. 1912829 (I), 1912830 (II), 1912831 (III), the metal atoms are bound by four bridging L molecules without forming the metal–metal bond (the M···M distances are 4.595 Å in I, 4.4637 Å in II, and 4.584 Å in III).
799-803
New Сu(II) and Co(II) Complexes with 2-Benzoylpyridine: Syntheses and Crystal Structures
Abstract
Two new mononuclear complexes [Cu(Bzpy)2(Cl)2] (I) and [Cо(Bzpy)2(H2O)2](BF4)2 (II) are synthesized by the reactions of 2-benzoylpyridine (Bzpy) with the copper(II) and cobalt(II) salts. It is found by X-ray diffraction analysis (CIF files CCDC nos. 1908081 (I) and 1908080 (II)) that complex I is molecular and complex II is of the ionic type. Two neutral bidentate-chelate N,O-ligands Bzpy are coordinated to the complexing atom in both complexes. The Cl– anions supplement the coordination polyhedra to octahedra in complex I, and the water molecules supplement the coordination polyhedra to octahedra in complex II. The [BF4]– anions in complex II compensate the positive charge of the complex cations and are bound to them by intermolecular hydrogen bonds О–H···F along with electrostatic interactions.
804-808
Synthesis, Characterization and Crystal Structures of Oxidovanadium(V) and Dioxidomolybdenum(VI) Complexes Derived from 2-bromo-N'-(2-hydroxy-3-methoxybenzylidene)benzohydrazide with Catalytic Property
Abstract
A hydrazone compound 2-bromo-N'-(2-hydroxy-3-methoxybenzylidene)benzohydrazide (H2L) was prepared and characterized by IR, UV-Vis and NMR spectra. Based on the hydrazone compound, a new oxidovanadium(V) and a new dioxidomolybdenum(VI) complexes, [VO(L)(OEt)(EtOH)] (I) and [MoO2(L)(OH2)] (II), were prepared and characterized by IR, UV-Vis, NMR spectra, and single crystal X-ray diffraction (CIF files nos. 1866755 (I) and 1866756 (II)). Complex I crystallizes as the monoclinic space group P21/c with unit cell dimensions a = 12.8733(12), b = 13.5088(13), c = 11.9262(11) Å, β = 91.765(2)°, V = 2073.0(3) Å3, Z = 4, R1 = 0.0524, wR2 = 0.1329, GOOF = 1.245. Complex II crystallizes as the monoclinic space group P21/c with unit cell dimensions a = 8.1140(9), b = 16.2975(19), c = 13.4318(15) Å, β = 106.456(2)°, V = 1703.4(3) Å3, Z = 4, R1 = 0.0296, wR2 = 0.0728, GOOF = 1.046. X-ray analysis indicates that the complexes are mononuclear species with the metal atoms in octahedral coordination. The complexes were studied for catalytic oxidation property on some olefins with tert-butyl hydrogen peroxide as oxidant.
809-816
A New Coordination Polymer for Effective 5-fluorouracil Loading and Anti-lung Cancer Activity Study
Abstract
A new three-dimensional porous coordination polymer with the formula of [Ba(HTATB)-(H2O)](DMF)2 (I) has been solvothermally synthesized from 4,4′,4″-s-triazine-2,4,6-triyltribenzoic acid (H3TATB) and Ba(NO3)2 under DMF media and characterized by single crystal X-ray diffraction (CIF file CCDC no. 1856562) and elemental analysis. The efficient encapsulation of an anticancer drug 5-fluorouracil (5-FU) on the desolvated I (Ia) has been studied both experimentally and computationally. In addition, in vitro anti-lung cancer activity of compounds I and 5-FU loaded 1a have also been evaluated using MTT assay.
817-823
Syntheses, Structure, and Luminescent Property of a New 2D Nd(III) Coordination Polymer Based on 4′-(4-Carboxyphenyl)-4,2′:6′,4″-Terpyridine
Abstract
A new lanthanide coordination polymer (Ln-CP) based on Nd(III), [Nd2(Cptpy)2(Glu)2(H2O)2]n · 5n(H2O) (Ι) (HCptpy = 4′-(4-carboxyphenyl)-4,2′:6′,4″-terpyridine and H2Glu = glutaric acid), have been hydrothermally synthesized and characterized by elemental analysis, IR, single crystal X-ray diffraction (CIF file CCDC no. 1857154) and thermal analyses. Single crystal X-ray analysis (CIF file CCDC no. 1857154) reveals that compound Ι displays a (4,5)-connected 2D topological net and the Schläfli symbol of (3.43.52)(32.44.52.62), which is further extended into a 3D supramolecular network by hydrogen bonds. Additionally, the near-infrared (NIR) luminescence of Ι was investigated in the solid state at room temperature.
824-829