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Vol 45, No 1 (2019)
- Year: 2019
- Articles: 10
- URL: https://journals.rcsi.science/1070-3284/issue/view/13356
Article
Complexes of Co(II), Ni(II), and Cu(II) with (Z)-10-(2-(4-Amino-5-Thioxo-4,5-Dihydro-1H-1,2,4-Triazol-3-yl)hydrazono)-9-Phenanthrone: Synthesis, Spectral Studies, and Quantum Chemical Simulation of the Structures
Abstract
The complexes of (Z)-10-(2-(4-amino-5-thioxo-4,5-dihydro-1Н-1,2,4-triazol-3-yl)hydrazono)-9-phenanthrone (HL) with the Co(II), Ni(II), and Cu(II) salts, [CoLAcDMF] (I), [NiLAcDMF] (II), [CuL(Н2О)]ClO4 (III), and [CuLAc] (IV), are synthesized and studied. The titration of a solution of HL in DMF with aqueous solutions of CoAc2, NiAc2, Cu(ClO4)2, CuAc2, Cd(NO3)2, or ZnSO4 leads to the bathochromic shift of the long-wavelength absorption band by 35–77 nm in the UV spectra. The formation constants and compositions of the complexes in solutions are determined from the results of titration. The structures of complexes I–IV are proposed on the basis of the DFT calculations and spectral data: the ligand being in the deprotonated form of the thione tautomer is coordinated by the metal cations through the oxygen atom of the carbonyl group and the nitrogen atoms of the hydrazo and amino groups to form two metallocycles, six- and five-membered (6 + 5). The coordination mode is completed by the acetate ion and DMF molecule (in I and II), acetate ion (in IV), or Н2О molecule (in III).
1-10
Coordination Polymers of Zn and Cd Based on Two Isomeric Azine Ligands: Synthesis, Crystal Structures, and Luminescence Properties
Abstract
Metal-organic 1D coordination polymers of Zn(II) and Cd(II), [{Zn(3-Bphz)(H2O)4}(3-Bphz)(NO3)2]n (I), [Zn(3-Bphz)I2]n (II), [Cd(3-Bphz)I2]n (III), [Cd(4-Bphz)(CH3COO)2(H2O)]n (IV), and [Cd(4-Bphz)(NO3)2(H2O)2]n (V), containing azines of the N,N' type, 1,2-bis(pyridin-3-ylmethylene)hydrazine (3-Bphz) and 1,2-bis(pyridin-4-ylmethylene)hydrazine (4-Bphz), as bridging ligands are synthesized. The compositions and structures of the compounds are confirmed by the data of elemental analysis, IR and NMR spectroscopy, and single-crystal X-ray diffraction analysis (CIF files CCDC nos. 1812634–1812638 for I–V). Coordination polymers I–III have zigzag structures. The octahedral environment of the Zn2+ ion in compound I is formed by two 3-Bphz ligands and four water molecules. The external sphere contains nitrate anions and uncoordinated 3-Bphz molecules. In isomorphous compounds II and III, the tetrahedral environment of the metal is formed by two nitrogen atoms of two bridging 3-Bphz ligands and two iodine atoms. Coordination polymers IV and V are linear. The coordination polyhedron of the Cd2+ ion in compound IV is a pentagonal bipyramid, two vertices of which are occupied by the nitrogen atoms of two 4-Bphz molecules, and the equatorial plane is formed by two bidentate-chelating acetate anions and one water molecule. In compound V, the octahedral environment of the Сd2+ ion is formed by two molecules of the 4-Bphz ligand, two monodentate nitrate anions, and two water molecules. All complexes are weak luminophores emitting in the blue-green spectral range.
11-21
Pseudo-Polymeric Mercury(II) Morpholinedithiocarbamate [Hg{S2CN(CH2)4O}2]n: Supramolecular Structure (a Role of Secondary Hg···S Bonds), 13C and 15N CP-MAS NMR Spectra, and Thermal Behavior
Abstract
A new representative of mercury(II) dithiocarbamate complexes, crystalline bis(morpholinedithiocarbamato-S,S')mercury(II) with the pseudo-1D-polymeric structure, is preparatively synthesized. The structure is characterized by 13С and 15N MAS NMR spectroscopy and X-ray diffraction analysis (CIF file CCDC no. 1821609). Pairs of symmetric secondary Hg⋅⋅⋅S bonds (3.400 Å) combine mononuclear [Hg{S2CN(CH2)4O}2] molecules, including planar polygons [HgS4], into a linear pseudo-polymeric chain. The study of the thermal behavior shows that the two-stage mass loss detected by thermogravimetry is due to the thermal destruction of the complex with the formation of HgS and its subsequent sublimation.
22-29
Samarium, Europium, and Gadolinium Complexes with 4-(2,1,3-Benzothiadiazol-4-ylamino)pent-3-en-2-onate
Abstract
New lanthanide complexes with 4-(2,1,3-benzothiadiazol-4-ylamino)pent-3-en-2-onate (L–) [Ln(L)3] are synthesized using two methods: by the reaction of Ln(N(SiMe3)2)3 with the protonated form of the ligand LH (Ln = Sm, Gd) and by the reaction of LnCl3 (Ln = Eu) with LH in the presence of KN(SiMe3)2 as a base. According to the X-ray diffraction data, the synthesized complexes [Ln(L)3] · 0.5Solv (Solv = THF, C7H8) are isotypical (CIF files CCDC nos. 1826520, 1826521, and 1826522 for Sm, Eu, and Gd, respectively). A specific feature of the structures is the disordering of the metal atom and one of the ligands over two positions when the fragments of the ligands are arranged via the head-to-tail type occupying the same volume of the space. This probably leads to failure in the crystal lattice. The photoluminescence spectra of [Sm(L)3] · 0.5THF are recorded. A relationship between the coordination mode of the ligand and the position of the long-wavelength band of the electron transitions in the complexes with the L– ligand is revealed.
30-35
Effect of Synthesis Conditions on the Molecular and Crystal Structures of Heterometallic 1D-Polymeric Acetate Complexes with the {Dy2Co}n Motif
Abstract
New heterometallic 1D-polymeric acetate complexes with the {Dy2Co}n motif of the metallic framework, [Dy2Co(CH3COOO)8(H2O)4]n ∙ 6nH2O (I) and [Dy2Co(CH3COOO)8(H2O)2]n ∙ 2nCH3COOH (II), are synthesized and studied. The molecular structures of the obtained compounds (CIF files CCDC nos. 1861619 (I) and 1861620 (II)) differ by the qualitative composition of the coordination environment of Dy as well as by the coordination modes of the acetate anions, which substantially affects the lengths of the corresponding Dy···Dy and Dy···Co distances in the chain. The mentioned distinctions and different solvate compositions of I and II are determined by the synthesis conditions of the complexes.
36-41
Polymorphism of the Double Octa(ε-caprolactam)europium(III) Hexa(isothiocyanato)chromate(III) Complex
Abstract
A new structural polymorph of the compound [Eu(ε-C6H11NO)8][Cr(NCS)6] was isolated from the solid product mixture obtained in the reaction of EuCl3, K3[Cr(NCS)6], and ε-caprolactam (ε-C6H11NO) in aqueous solution. The crystals were triclinic, space group. P\(\bar {1}\), Z = 2, a = 14.2320(4) Å, b = 14.5298(4) Å, c = 17.0014(5) Å, α = 92.4190(10)°, β = 91.0880(10)°, γ = 108.4850(10)°, V = 3329.39 Å3, ρ(calcd.) = 1.454 g/cm3, R1 = 0.0419 (CIF file CCDC no. 1827162).
42-46
Nitrilotris(methylenephosphonic) Complexes of Lanthanides [Na(H2O)x]2[LnIIINa6H(H2O)10{N(CH2PO3)3}2] · nH2O (LnIII = Pr, Nd)
Abstract
The sodium salts of lanthanide nitrilotris(mehylenephosphonate) complexes [Na(H2O)x]2[LnIIINa6H(H2O)10{N(CH2PO3)3}2] · nH2O, where LnIII = Pr (I), and Nd (II), were prepared, isolated, and studied. The isostructural crystals are monoclinic, space group P21/c, Z = 2; for complex I, a = 11.8168(7), b = 10.5403(9), c = 19.8094(10) Å, β = 94.232(5)°; for complex II, a = 11.7999(2), b = 10.5495(2), c = 19.7976(3) Å, β = 94.158(2)°. The lanthanide ions are coordinated at the center of a cage consisting of two {N(CH2PO3)3} acid residues and six sodium ions, which form P–O–Na–O–P bridges. The Ln coordination polyhedron is a regular rhombohedron (CIF files CCDC nos. 1825702 (I), 1825700 (II)).
47-55
Methyl Propiolate Cluster Complex (Ph4P)2[W6I8(C≡C–C(O)OCH3)6]
Abstract
A new organometallic iodide cluster complex (Bu4N)2[W6I8(C≡C–C(O)OCH3)6] (I), analogous to the previously described (Bu4N)2[Mo6I8(C≡C–C(O)OCH3)6], was obtained by the reaction of (Bu4N)2[W6I14] with silver methyl propiolate AgC≡C–C(O)OCH3. The crystal structure was established for the tetraphenylphosphonium salt (Ph4P)2[W6I8(C≡C–C(O)OCH3)6] (II). According to X-ray diffraction (CIF file CCDC no. 1829205), tungsten atoms in II are coordinated by terminal carbon atoms of methyl propiolate ligands at W–C distances of 2.220(12)–2.268(14) Å. The methyl propiolate complexes were characterized by electrospray mass spectrometry, 1H and 13C NMR spectroscopy, elemental analysis, and IR spectroscopy.
56-61
Synthesis, Characterization, and Catalytic Activity of Heteroleptic Rhodium Complex for C–N Couplings
Abstract
We have reported synthesis of complex [Rh(COD)(L{Me})Cl] (III), where L{Me} (II) is N-(1-methylpyridin-4(1H)-ylidene)benzamide and COD is 1,5-cyclooctadiene. Monodentate ligand L{Me} was synthesized by deprotonation of [HL{Me}][OTf] (I) with sodium hydride. [HL{Me}][OTf] was synthesised by methylation of N-(pyridin-4-yl)benzamide (HL) with methyl triflate. All the three synthesized compounds were characterized by FT-IR, NMR (1H and 13C), elemental and MS analyses. The structure of complex I was further explored with single crystal XRD and computational studies. Complex I was found as a good catalyst for C–N coupling reactions. Molecular docking revealed strong binding of rhodium complex with myoglobin.
62-73
An Uncommon Nanocage 3D Metal–Organic Framework Built from a Tetracarboxylate Ligand: Photoluminescence and Photocatalytic Properties
Abstract
A new Eu(II)-based complex [H2N(Me)2][Eu3(L)2(HCOO)2(DMF)2(H2O)](I) (H4L = 3,5'-di(3',5'-dicarboxylphenyl)pyridine) has been synthesized and structurally characterized. Single-crystal X-ray analysis (CIF file CCDC no. 1559225) reveals that compound I has 3D (4.62)(4.62)(42.67.86) topology. The emission spectra of I is dominated by four characteristic bands and shows strong luminescent feature. Furthermore, the photocatalytic properties of I for degradation of the methyl violet and Rhodamine B have been explored.
74-79