Synthese und Struktur der Vanadyl-, Cobalt(III)-, Nickel(II)-, Kupfer(II)-, Zink(II)- und PalIadium(II)-Komplexe eines vierzehngliedrigen ungesättigten Tetraazadibenzo-Makrocyclus / Synthesis and Structures of the Vanadyl, Cobalt(III), Nickel(II), Copper(II), Zinc(II) and Palladium(II) Complexes of a 14-Membered Unsaturated Tetraazadibenzo Macrocycle

The synthesis and structural characterisation of complexes of the 14-membered macrocyclic trans-N4 dibenzo ligand 7,8,9,16,17.18-hexahydrodibenzo[e,l][1,4, 8.11]-tetraazacyclotetradecine (L1) is described. The crystal structures of six compounds were determined by single crystal X-ray diffraction. In [CuL1]2+ the metal atom is tightly bound within the macrocyclic cavity. The Cu-N bonds [201.2(3) and 191.8(3) pm] are rather short. Zn(II) is penta-coordinated in [Zn(L1)Cl]+ with the metal center outside the cavity. L1 is deprotonated at one or both secondary amine functions in the complexes [Ni(L1-H)]+, [Co(L1-2H)]+, [VO(L1-2H)] and [Pd(L1-2H)]. With the exception of [VO(L1-2H)] the metal ions assume nearly square planar N4-coordination, which is very rare for Co(III). Salts of [Co(L1-2H)]+ display a temperature independent magnetic moment of 0,64 B. M. The nickel, cobalt and palladium complexes show remarkably short metal-nitrogen bond distances: Ni-N [183.8(8)], Co-N [181.8(2)] and Pd-N [194.5(6) pm], respectively. The UV/Vis and EPR spectra, and the electrochemical behaviour of some of these complexes are also discussed.

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Molecular Structures and Catalytic Activity of Palladium Complexes Derived from Lutidine-bridged Bis(benzimidazolin-2-ylidene) Ligands

Zeitschrift für Naturforschung B ◽

10.1515/znb-2007-0308 ◽

2007 ◽

Vol 62 (3) ◽

pp. 357-361 ◽

Cited By ~ 12

Author(s):

Mareike C. Jahnke ◽

Tania Pape ◽

F. Ekkehardt Hahn

Keyword(s):

Palladium Complexes ◽

Molecular Structures ◽

Palladium Acetate ◽

Coupling Reactions ◽

Slow Evaporation ◽

X Ray Diffraction ◽

Cationic Complex ◽

X Ray ◽

Methanol Solutions ◽

Square Planar

Reaction of lutidine-bridged dibenzimidazolium dibromides 1 - 4 with palladium acetate gives pincer-type palladium complexes of the type [Pd(L)Br]Br [5]Br-[8]Br. Crystals suitable for an X-ray diffraction study have been obtained by slow evaporation of the solvent from dichloromethane/methanol solutions of [7]Br and [8]Br. The crystal structure of [7]+ reveals a pincer topology of the cationic complex with a distorted square-planar coordination geometry at the metal center. From a solution of complex [8]Br, a dinuclear byproduct [9]+ was obtained with two bis(benzimidazolin- 2-ylidene) ligands coordinating in a bridging fashion. The pincer-type palladium complexes [5]Br- [8]Br were tested as precatalysts in Suzuki coupling reactions.

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Komplexe eines vierzehngliedrigen Tetraazadibenzo-Makrocyclus. Strukturen des freien und zweifach protonierten Liganden und seiner Nickel(II)-, Kupfer(II)-, Zink(II)- und Palladium(II)-Komplexe / Complexes of a 14-Membered N4 Dibenzo Macrocycle. Crystal Structures of the Free and Diprotonated Ligand and of its Nickel(II), Copper(II), Zink(II) and Palladium (II) Complexes

Zeitschrift für Naturforschung B ◽

10.1515/znb-1996-0618 ◽

1996 ◽

Vol 51 (6) ◽

pp. 869-878 ◽

Cited By ~ 4

Author(s):

Ralf Feldhaus ◽

Jens Köppe ◽

Rainer Mattes

Keyword(s):

Hydrogen Bonds ◽

Crystal Structures ◽

Free Ligand ◽

X Ray Diffraction ◽

Intermolecular Hydrogen Bonds ◽

Structural Characterisation ◽

Metal Atoms ◽

Intramolecular Hydrogen ◽

Nitrogen Bond ◽

Macrocyclic Cavity

Abstract The synthesis and structural characterisation of complexes of the 14-membered macrocyclic trans-N4 dibenzo ligand 5,6,7,8,9,14.15,16,17,18-decahydrodibenzo[e,l][1,4, 8,11]-tetraazacyclotetradecine (L2) is described. The crystal structures of six compounds were determined by single crystal X-ray diffraction. The free ligand L2 has a saddle-shaped structure with short intramolecular hydrogen bonds. The N-N distances are 289 pm. The diprotonated species [H2L2]2+ has a different conformation due to intra- and intermolecular hydrogen bonds. The ligand is folded along an N-N axis in c/s-[Ni(L2)(H2O)2]2+, but displays a saddleshaped structure in the Cu(II), Zn(II) and Pd(II) complexes with a more or less planar arrangement of the four N donor atoms. The metal atoms are incorporated within the macrocyclic cavity in [Cu(L2)(CF3SO3)]+ and [Pd(L2)]2+. The metal-to-nitrogen bond lengths herein are rather small. Zn(II) is five-coordinate in [Zn(L2)(Cl)]+. The coordination polyhedron is intermediate between a trigonal bipyramid and a square pyramid. In all complexes the metalto- ligand distances originating at the nitrogen atoms in β-position (with respect to the aromatic ring) are significantly shorter then the donor bonds of the ‘anilinic’ N atoms

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Studies about Electrochemical Plating with Zinc - nickel Alloys - the Influence of Deposition Potential on Stoichiometric Composition

Revista de Chimie ◽

10.37358/rc.08.9.1957 ◽

2008 ◽

Vol 59 (9) ◽

Cited By ~ 2

Author(s):

Violeta Vasilache ◽

Gheorghe Gutt ◽

Traian Vasilache

Keyword(s):

Nickel Alloys ◽

Stoichiometric Composition ◽

Nickel Chloride ◽

Deposition Potential ◽

X Ray Diffraction ◽

Pure Zinc ◽

X Ray ◽

Nickel Cobalt ◽

Cobalt Iron ◽

Electrochemical Plating

The electrochemical deposition of zinc and combinations with elements of the 8th group of the Periodic System (nickel, cobalt, iron) have good properties for anticorrosive protection, compared with pure zinc. For steel pieces, these films delay apparition and formation of white and red iron oxide. We used solutions with different concentrations of zinc chloride, nickel chloride and potassium chloride. To analyze the results we used the optic microscope and the X-ray diffraction.

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Synthesis and Structure of a Clathrated Two-Dimensional Metal-Organic Framework: [Cd(4,4'-bpy)2(H2O)2](ClO4)2·(L)2·H2O (L = Bis(1-pyrazinylethylidene)hydrazine)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc20080024 ◽

2008 ◽

Vol 73 (1) ◽

pp. 24-31

Author(s):

Dayu Wu ◽

Genhua Wu ◽

Wei Huang ◽

Zhuqing Wang

Keyword(s):

Metal Organic Framework ◽

Channel Structure ◽

Two Dimensional ◽

X Ray Diffraction ◽

Guest Molecules ◽

X Ray ◽

Square Planar ◽

Metal Organic ◽

Aqueous Meoh ◽

Organic Framework

The compound [Cd(4,4'-bpy)2(H2O)2](ClO4)2·(L)2 was obtained by the reaction of Cd(ClO4)2, bis(1-pyrazinylethylidene)hydrazine (L) and 4,4'-bipyridine in aqueous MeOH. Single-crystal X-ray diffraction has revealed its two-dimensional metal-organic framework. The 2-D layers superpose on each other, giving a channel structure. The square planar grids consist of two pairs of shared edges with Cd(II) ion and a 4,4'-bipyridine molecule each vertex and side, respectively. The square cavity has a dimension of 11.817 × 11.781 Å. Two guest molecules of bis(1-pyrazinylethylidene)hydrazine are clathrated in every hydrophobic host cavity, being further stabilized by π-π stacking and hydrogen bonding. The results suggest that the hydrazine molecules present in the network serve as structure-directing templates in the formation of crystal structures.

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Ternary Antimonides RE4T7Sb6 (RE=Gd–Lu; T =Ru, Rh) with Cubic U4Re7Si6-type Structure

Zeitschrift für Naturforschung B ◽

10.5560/znb.2013-3181 ◽

2013 ◽

Vol 68 (9) ◽

pp. 971-978 ◽

Cited By ~ 2

Author(s):

Inga Schellenberg ◽

Ute Ch. Rodewald ◽

Christian Schwickert ◽

Matthias Eul ◽

Rainer Pöttgen

Keyword(s):

Magnetic Susceptibility ◽

Single Crystal ◽

Magnetic Moment ◽

Induction Furnace ◽

X Ray Diffraction ◽

Temperature Dependent ◽

X Ray ◽

Antiferromagnetic Ordering ◽

Arc Melting ◽

Intermediate Valent

The ternary antimonides RE4T7Sb6 (RE=Gd-Lu; T =Ru, Rh) have been synthesized from the elements by arc-melting and subsequent annealing in an induction furnace. The samples have been characterized by powder X-ray diffraction. Four structures were refined on the basis of single-crystal X-ray diffractometer data: U4Re7Si6 type, space group Im3m with a=862.9(2) pm, wR2=0.0296, 163 F2 values for Er4Ru7Sb6; a=864.1(1) pm, wR2=0.1423, 153 F2 values for Yb4Ru7Sb6; a=872.0(2) pm, wR2=0.0427, 172 F2 values for Tb4Rh7Sb6; and a=868.0(2) pm, wR2=0.0529, 154 F2 values for Er4Rh7Sb6, with 10 variables per refinement. The structures have T1@Sb6 octahedra and slightly distorted RE@T26Sb6 cuboctahedra as building units. The distorted cuboctahedra are condensed via all trapezoidal faces, and this network leaves octahedral voids for the T1 atoms. The ruthenium-based series of compounds was studied by temperature-dependent magnetic susceptibility measurements. Lu4Ru7Sb6 is Pauli-paramagnetic. The antimonides RE4Ru7Sb6 with RE=Dy, Ho, Er, and Tm show Curie-Weiss paramagnetism. Antiferromagnetic ordering occurs at 10.0(5), 5.1(5) and 4.0(5) K for Dy4Ru7Sb6, Ho4Ru7Sb6 and Er4Ru7Sb6, respectively, while Tm4Ru7Sb6 remains paramagnetic. Yb4Ru7Sb6 is an intermediate-valent compound with a reduced magnetic moment of 3.71(1) μB per Yb as compared to 4.54 μB for a free Yb3+ ion

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X-Ray diffraction investigation of tris(ethylphenylamido)phosphazohydride (EtPhN) 3P=NH and nature of the phosphorus-nitrogen bond

Theoretical and Experimental Chemistry ◽

10.1007/bf00521324 ◽

1984 ◽

Vol 20 (3) ◽

pp. 309-316

Author(s):

M. Yu. Antipin ◽

Yu. T. Struchkov ◽

Yu. P. Egorov

Keyword(s):

X Ray Diffraction ◽

X Ray ◽

Nitrogen Bond

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Crystal and molecular structure and 31P and 195Pt nmr spectroscopy of [Pt3S2(PMe2Ph)6][BEt4]2; a trinuclear complex containing triply-bridging sulphide ligands

Canadian Journal of Chemistry ◽

10.1139/v84-116 ◽

1984 ◽

Vol 62 (4) ◽

pp. 696-702 ◽

Cited By ~ 19

Author(s):

Gordon William Bushnell ◽

Keith Roger Dixon ◽

Reiko Ono ◽

Alan Pidcock

Keyword(s):

Trinuclear Complex ◽

Complete Analysis ◽

Monoclinic Space Group ◽

X Ray Diffraction ◽

X Ray ◽

Metal Interactions ◽

Nuclear Magnetic Resonance Spectra ◽

Square Planar ◽

Metal Metal ◽

Pd Complexes

An X-ray diffraction study of [Pt3S2(PMe2Ph)6][BEt4]2 shows that it crystallises in the monoclinic space group, C2/c, with a = 15.447(2), b = 18.033(3), c = 26.505(5) Å, β = 96.73(2)°. The cation consists of three, distorted, square-planar cis-PtS2(PMe2Ph)2 moieties combined by sharing of the two sulphur atoms to produce a central Pt3S2 unit with C2 symmetry and Pt—Pt distances of 3.182(1) Å (one edge) and 3.108(1) Å (two edges). Complete analysis and computer simulation of 31P{1H} and 195Pt{1H} nuclear magnetic resonance spectra give values for 1J(Pt—P), 3202 Hz; 3J(Pt—P), −25 Hz; and 2J(Pt—Pt), 476 Hz. The structure is compared with previous results for analogous Ni and Pd complexes and the structural and nmr parameters are discussed with reference to the possibility of metal–metal interactions.

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Applications of High-Resolution Powder X-Ray Diffraction

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.130.7 ◽

2007 ◽

Vol 130 ◽

pp. 7-14 ◽

Cited By ~ 4

Author(s):

Andrew N. Fitch

Keyword(s):

High Resolution ◽

Synchrotron Radiation ◽

Powder Diffraction ◽

X Rays ◽

X Ray Diffraction ◽

Crystalline Materials ◽

X Ray ◽

Structural Characterisation ◽

Pdf Analysis

The highly-collimated, intense X-rays produced by a synchrotron radiation source can be harnessed to build high-resolution powder diffraction instruments with a wide variety of applications. The general advantages of using synchrotron radiation for powder diffraction are discussed and illustrated with reference to the structural characterisation of crystalline materials, atomic PDF analysis, in-situ and high-throughput studies where the structure is evolving between successive scans, and the measurement of residual strain in engineering components.

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