557-42-6Relevant articles and documents
Tripodal ligands: Design of distorted coordination polyhedra in biomimetic metal complexes. Crystal structures of [Zn(SCN)(ntb)](SCN) · iPrpOH and [Fe(acac)(ntb)](ClO4)2 · 2 CH2Cl2 · iPrpOH, ntb = N-tris(2-benzimidazolylmethyl)amine
Nazikkol, Cetin,Wegner, Rainer,Bremer, Johannes,Krebs, Bernt
, p. 329 - 336 (1996)
The tripodal ligand N-tris(2-benzimidazolylmethyl)amine (ntb) was used for the preparation of zinc(II) and iron(III) complexes, [Zn(SCN)(ntb)](SCN) · iPrpOH (1) and [Fe(acac)(ntb)](ClO4)2 · 2 CH2Cl2 · iPrpOH (2). 1 has a highly distorted trigonal-bipyramidal ZnN5 coordination geometry. The donor atoms are nitrogens of one amine, three benzimidazoles and one SCN-. A striking feature of the complex is the length of the Zn-Namine bond of 2.539(6) A. The octahedral N4O2 coordination sphere of the iron in 2 is less distorted than that of the zinc in 1. The metal is surrounded by an amine and three benzimidazole nitrogens of the ligand and two oxygens of the bidentate acetylacetonate co-ligand. The Fe-O bond lengths differ by about 0.1 A. As for the unusual long Zn-N bond in 1 this is a result of a trans effect. 1 crystallizes in the space group P1 with: a = 9.530(1) A, b = 13.402(1) A, c = 13.578(2) A, α = 98.83(1), β = 95.19(1), γ = 101.21(1)°, Z = 2; 2 is also triclinic, space group P1, with: a = 9.875(6) A, b = 12.929(10) A, c = 18.635(15) A, α = 94.95(8)°, β = 101.01(6)°, γ = 111.09(4)°, Z = 2. Johann Ambrosius Barth 1996.
Crystal structure solid-state cross polarization magic angle spinning 13C NMR correlation in luminescent d10 metal-organic frameworks constructed with the 1,2-bis(1,2,4-triazol-4-yl)ethane ligand
Habib, Hesham A.,Hoffmann, Anke,Hopped, Henning A.,Sieinfeld, Gunther,Janiak, Christoph
, p. 2166 - 2180 (2009)
Hydrothermal reactions of 1,2-bis(1,2,4-triazol-4-yl)ethane (btre) with copper(ll), zinc(ll), and cadmium(ll) salts have yielded the dinuclear complexes [Zn2CI4(μ2-btre)2] (1) and [Zn2Br4(μ
Zn(NCS)2-3-cyanopyridine Coordination Compounds: Synthesis, Crystal Structures, and Thermal Properties
Jochim, Aleksej,Jess, Inke,N?ther, Christian
, p. 212 - 218 (2019)
The reaction of different stoichiometric amounts of Zn(NCS)2 with 3-cyanopyridine in different solvents leads to the formation of several new coordination compounds, which were structurally characterized and investigated for their thermal behavior. In Zn(NCS)2(3-cyanopyridine)4 (1) and Zn(NCS)2(3-cyanopyridine)2(H2O)2·(3-cyanopyridine)2 (2) the zinc cations are octahedrally coordinated by two terminally N-bonded thiocyanate anions and four 3-cyanopyridine (1) or two 3-cyanopyridine and two water molecules (2) within slightly distorted octahedra. Zn(NCS)2(3-cyanopyridine)2 (3) and Zn(NCS)2(3-cyanopyridine)2·(H2O)0.5 (3-H2O) also form discrete complexes but with tetrahedrally coordinated Zn cations. Upon heating compound 1 decomposes without the formation of any intermediate compound. In contrast, compound 2 loses the water molecules in the first step and transforms into compound 1. Surprisingly, upon further heating a second TG step is observed, in which compound 3 is formed as an intermediate, which is not observed if compound 1 is heated directly. The tetrahedral complex 3 melts leading to the formation of an amorphous phase. If the hemihydrate 3-H2O is heated, it transforms into 3 via melting and crystallization but there are hints that a metastable phase might form as intermediate on water removal.
Selective Synthesis and Thermodynamic Relations of Polymorphic Co(NCS)2-4-Dimethylaminopyridine Coordination Compounds
Neumann, Tristan,Jess, Inke,Pielnhofer, Florian,N?ther, Christian
, p. 4972 - 4981 (2018)
Reaction of Co(NCS)2 with 4-dimethylaminopyridine (DMAP) leads to the formation of four new compounds. The crystal structures of Co(NCS)2(DMAP)2(H2O)2·2H2O (1), Co(NCS)2(DMAP)2(MeOH)2 (2) and Co(NCS)2(DMAP)2(MeCN)2 (3) consist of discrete simple solvato complexes in which the Co cations are octahedrally coordinated by two terminally N-bonded thiocyanate anions, two DMAP ligands as well as two solvato ligands. Co(NCS)2(DMAP)2 (4/II) also forms discrete complexes, but the Co cations are tetrahedral coordinated by two anionic ligands and two DMAP ligands. Upon heating, the hydrate 1 transforms into 4/II, whereas the methanol solvate 2 transforms into a new polymorphic modification of Co(NCS)2(DMAP)2 (4/I). For structure determination the corresponding Zn(NCS)2 compound was prepared that is isotypic to 4/I. Solvent mediated conversion experiments prove that 4/II represents the thermodynamic stable form at room-temperature and density functional theory (DFT) calculations indicate that this form is also stable at 0 K. Upon heating both modifications show melting with the higher melting polymorph 4/I having the lower melting enthalpy. Temperature dependent X-ray powder diffraction shows that 4/II transforms into 4/I upon heating. All experimental results indicate, that both modifications are related by enantiotropism.
Synthesis, Crystal Structures, and Properties of M(NCS)2-3-aminomethylpyridine Coordination Compounds (M = Cd, Zn)
Neumann, Tristan,Germann, Luzia S.,Moudrakovski, Igor,Dinnebier, Robert E.,dos Santos Cunha, Cesar,Terraschke, Huayna,N?ther, Christian
, p. 1904 - 1912 (2017)
Reaction of Cd(NCS)2 or Zn(NCS)2 with 3-aminomethylpyridine (3-AMPy) leads to the formation of five compounds with the compositions [Cd(NCS)2(3-AMPy)2·(3-AMPy)]n (1-Cd), [M(NCS)2(3-AMPy)2]n [M = Cd (2-Cd), Zn (2-Zn)] [Cd(NCS)2(3-AMPy)]n (3-Cd), and [Zn(NCS)2(3-AMPy)]2 (3-Zn). In 1-Cd the Cd cations are linked by the 3-AMPy ligands into layers that consist of rings, built up of four Cd cations and four 3-AMPy ligands. These layers are stacked to form channels, in which the 3-AMPy solvate molecules are located. In the isotypic compounds 2-Cd and 2-Zn the metal cations are also linked into layers by the 3-AMPy ligands with an identical layer topology as that in 1-Cd, but a completely different conformation of the 3-AMPy ligand. In the most 3-AMPy deficient compound 3-Cd, the Cd cations are linked by μ-1,3-bridging thiocyanate anions and 3-AMPy ligands into chains, that are further connected into layers by additional anionic ligands. In 3-Zn two Zn cations are linked by pairs of 3-AMPy ligands into discrete dimers. Thermoanalysis and X-ray powder diffraction (XRPD) investigations show that upon heating 1-Cd transforms into 2-Cd and 2-Zn into 3-Zn. The compounds 2-Cd, 3-Cd, 2-Zn, and 3-Zn present ligand-based luminescence in the blue-green spectral range with maxima between 21276 and 21795 cm–1.
Synthesis, crystal structures, and thermal properties of new zinc(II) thiocyanato coordination compounds
Bhosekar, Gaurav,Boeckmann, Jan,Jess, Inke,Naether, Christian
, p. 2595 - 2601 (2010)
Reaction of zinc(II) thiocyanate with pyrazine, pyrimidine, pyridazine, and pyridine leads to the formation of new zinc(II) thiocyanato coordination compounds. In bis(isothiocyanato-N)-bis(μ2-pyrazine-N,N) zinc(II) (1) and bis(isothiocyanato-N)-bis(μ2-pyrimidine-N,N) zinc(II) (2) the zinc atoms are coordinated by four nitrogen atoms of the diazine ligands and two nitrogen atoms of the isothiocyanato anions within slightly distorted octahedra. The zinc atoms are connected by the diazine ligands into layers, which are further linked by weak intermolecular S···S interactions in 1 and by weak intermolecular C-H···S hydrogen bonding in 2. In bis(isothiocyanato-N)-bis(pyridazine-N) (3) discrete complexes are found, in which the zinc atoms are coordinated by two nitrogen atoms of the isothiocyanato ligands and two nitrogen atoms of the pyridazine ligands. The crystal structure of bis(isothiocyanato-N)-tetrakis(pyridine-N) (4) is known and consists of discrete complexes, in which the zinc atoms are octahedrally coordinated by two thiocyanato anions and four pyridine molecules. Investigations using simultaneous differential thermoanalysis and thermogravimetry, X-ray powder diffraction and IR spectroscopy prove that on heating, the ligand-rich compounds 1, 2, and 3 decompose without the formation of ligand-deficient intermediate phases. In contrast, compound 4 looses the pyridine ligands in two different steps, leading to the formation of the literature known ligand-deficient compound bis(isothiocyanato-N)-bis(pyridine-N) (5) as an intermediate. The crystal structure of compound 5 consists of tetrahedrally coordinated zinc atoms which are surrounded by two isothiocyanato anions and two pyridine ligands. The structures and the thermal reactivity are discussed and compared with this of related transition metal isothiocyanates with pyrazine, pyrimidine, pyridazine, and pyridine. Copyright
Investigations on the structure diversity and thermal degradation behavior of CdII and ZnII thiocyanato coordination compounds based on 3-acetylpyridine as neutral co-ligand
Werner, Julia,Boeckmann, Jan,Naether, Christian
, p. 2257 - 2264 (2012)
Reaction of CdII and ZnII thiocyanate with 3-acetylpyridine leads to the formation of the new CdII and Zn II coordination compounds [Cd(NCS)2(3-acetylpyridine) 4] (1A), [Cd(NCS)2(3-acetylpyridine)2] n (1B), [Cd(NCS)2(3-acetylpyridine)]n (1C) and [Zn(NCS)2(3-acetylpyridine)2] (2A). Compound 1A consists of discrete complexes, in which the metal centers are octahedrally coordinated by four terminal bonded N-donor co-ligands and two terminal N-bonded thiocyanato anions. In compound 2A the metal centers are only tetrahedrally coordinated by two terminal bonded N-donor co-ligands and two terminal N-bonded thiocyanato anions. In compound 1B the CdII cations are octahedrally coordinated by two terminal bonded N-donor co-ligands and four thiocyanato anions. The metal centers are linked by μ-1, 3 bridging thiocyanato anions into chains. In compound 1C the metal cations are octahedrally coordinated by two μ-1, 5 bridging 3-acetyl-pyridine ligands and four μ-1, 3 bridging thiocyanato anions building up a three-dimensional coordination network. Investigations on the thermal degradation behavior of all compounds using simultaneous differential thermoanalysis and thermogravimetry as well as X-ray powder diffraction and IR spectroscopy prove that on heating compound 2A decompose without the formation of 3-acetylpyridine-deficient intermediates. In contrast, for compound 1A a stepwise decomposition is observed, leading to the formation of the 3-acetylpyridine-deficient compound [Cd(NCS)2(3- acetylpyridine)2]n (1B) which decomposes on further heating Copyright
An ultrasonic absorption study of the complex formation of zinc(II) thiocyanate in aqueous solution
Tamura, Kiyoshi
, p. 4539 - 4543 (1985)
A new method of analysis for the ultrasonic absorption of systems involving multiple coupled equilibria is described.The method consists of calculating the relaxation frequencies and amplitudes under a postulated reaction mechanism using trial values of the rate constants and volume changes and of comparing the computed absorption α/f2 (absorption coefficient over frequency squared) directly with the experimental one.Application of this method to the ultrasonic absorption study of aqueous zinc(II)-thiocyanate solutions reveals that the relaxation absorption is ascribed to the successive complex formation equilibria .The rate constants and volume changes ofthe above reactions are determined.The method proves to be especially effective when the absorption spectra are associated with multiple coupled equilibria and accordingly too broad to be separated to discrete relaxation processes by the usual method of analysis.
Supramolecular Metallacycles and Their Binding of Fullerenes
Ehnbom, Andreas,G?b, Christian R.,Oppel, Iris M.,Sturm, Lisa,Tobe, Yoshito
supporting information, (2020/03/19)
The synthesis of a new triaminoguanidinium-based ligand with three tris-chelating [NNO]-binding pockets and C3 symmetry is described. The reaction of tris-(2-pyridinylene-N-oxide)triaminoguanidinium salts with zinc(II) formate leads to the formation of cyclic supramolecular coordination compounds which in solution bind fullerenes in their spherical cavities. The rapid encapsulation of C60 can be observed by NMR spectroscopy and single-crystal X-ray diffraction and is verified using computation.
