Interconversion between square-planar palladium(II) and octahedral palladium(IV) centres in a sulfur-bridged trinuclear structure

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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The Crystal and Molecular Structure of the Trinuclear Complex Bis[(μ-S)-α,α′-{(2-mercapto-5-methylbenzene-1,3-diyl)di(methylidyne)di(azino)}bis(cyclohexane-methanol)ato(3-)]tripalladium(II), L2Pd3. A New Coordination Mode for the Robson-Type Ligand L3-

Australian Journal of Chemistry ◽

10.1071/ch9891057 ◽

1989 ◽

Vol 42 (7) ◽

pp. 1057 ◽

Cited By ~ 5

Author(s):

BF Hoskins ◽

IAS Mcdonald

Keyword(s):

Molecular Structure ◽

Coordination Mode ◽

Crystal And Molecular Structure ◽

Trinuclear Complex ◽

Binuclear Complexes ◽

Central Metal ◽

The Novel ◽

X Ray Diffraction ◽

Square Planar ◽

Oxygen Groups

The crystal and molecular structure of the trinuclear complex L2Pd3 has been determined by single-crystal X-ray diffraction techniques at room temperatures, 20°C. The quinquedentate binucleating ligand, L3-, is formally the trianion α,α′-[(2-mercapto-5-methylbenzene-1,3-diyl )di(methylidyne)di(azino)]bis(cyclohexaemethano)ato(3-). Crystals of L2Pd3 are triclinic, PI, with a 11.896(1), b 13.4103(7), c 17.451(3) � , α 75.66(1), β 79.93(1) and γ88.99(1)�, Z 2. The structure was solved by the normal Fourier methods and refined by a least-squares procedure which gave final R and R, values of 0.046 and 0.049 respectively for the 7769 statistically significant reflections. The approximately square-planar coordination environments of the palladium centres give rise to a boat-shaped arrangement in which an approximate, non-crystallographic, twofold axis normal to the plane of the central metal is evident. The notable feature of the structure lies in the novel coordination mode adopted by the binucleating ligand. With respect to the binuclear complexes of this ligand, an electronic reorganization has occurred in one of the sidearms of both ligands which enables the formation of the pair of hydrazine bridges and also causes two of the terminal oxygen groups to become non-coordinating.

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Intermolecular Interactions in the Crystal of a New Nickel(II)-cobalt(II)- nickel(II) Trinuclear Complex Containing a Macrocyclic Complex Ligand

Zeitschrift für Naturforschung B ◽

10.1515/znb-2004-0703 ◽

2004 ◽

Vol 59 (7) ◽

pp. 757-762 ◽

Cited By ~ 6

Author(s):

Xiao-Zeng Li ◽

Bao-Lin Liu ◽

Juen-Hong He ◽

Dai-Zheng Liao

Keyword(s):

Macrocyclic Complex ◽

Trinuclear Complex ◽

Supramolecular Network ◽

Coordination Environment ◽

X Ray ◽

Square Planar ◽

Distorted Octahedral ◽

Non Covalent Interactions ◽

Covalent Interactions ◽

Complex Ligand

A new trinuclear complex [Co(NiL)2(H2O)2](ClO4)2 was synthesized by using a macrocyclic complex ligand [NiL], where L is the dianion of diethyl-5,6,7,8,16,17-hexahydro-6,7-dioxo-16Hdibenzo[ e,n] [1,4,8,12]tetraazacyclopentadecine-13,19-dicarboxylate. X-ray analysis revealed that the two Ni(II) ions have the same distorted N4 square planar coordination geometries. The Co(II) ion resides in a distorted octahedral O6 coordination environment. In the crystal, π···π interaction between a phenyl ring and three non-aromatic π-systems involving Ni and N atoms was observed together with C-H···O and O-H···O hydrogen bonds. These non-covalent interactions link the dications and the perchlorate anions to form a 3D supramolecular network.

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Allylic derivatives of nickel and palladium

Canadian Journal of Chemistry ◽

10.1139/v81-145 ◽

1981 ◽

Vol 59 (6) ◽

pp. 996-1006 ◽

Cited By ~ 10

Author(s):

Kenneth S. Chong ◽

Steven J. Rettig ◽

Alan Storr ◽

James Trotter

Keyword(s):

Least Squares ◽

Trinuclear Complex ◽

Boat Conformation ◽

Coordination Geometry ◽

Orientational Disorder ◽

Full Matrix ◽

Space Group ◽

Coordination Sites ◽

Square Planar ◽

Derivatives Of

The synthesis of novel allylic derivatives of Ni and Pd incorporating the bispyrazolylgallate ligand Me2Ga(N2C5H7)2− is described. Pyrazolyl-bridged homobinuclear and trinuclear nickel allyl systems are also presented. Crystal structures of [Me2Ga(N2C5H7)2]Ni(η3-C3H5) and [(η3-C3H5)Ni(N2C5H7)2]2Ni are described. Crystals of the former are triclinic, a = 8.265(1), b = 10.487(1), c = 11.755(2) Å, α = 72.60(1), β = 87.28(1), γ = 67.58(1)°, Z = 2, space group [Formula: see text] and crystals of the latter are monoclinic, a = 7.9172(3), b = 10.6929(1), c = 16.9118(6) Å, β = 102.887(2)°, Z = 2, space group P21/c. Both structures were solved by Patterson and Fourier syntheses and were refined by full-matrix least-squares procedures to R = 0.026 and 0.025 for 3329 and 2914 reflections with I ≥ 3σ(I) respectively. In both structures the M—(N—N)2—M rings are in the boat conformation and the allyl groups display twofold orientational disorder. In [Me2Ga(N2C5H7)2]Ni(η3-C3H5) the nickel coordination may be regarded as square-planar with the allyl ligand occupying two coordination sites and the coordination about the gallium is distorted tetrahedral. Important bond lengths (corrected for libration) are: Ni—N, 1.926(2) and 1.929(2), Ni—C, 1.971(5)–2.025(3), Ga—N, 1.994(2) and 1.996(2), Ga—C, 1.966(3) and 1.988(3) Å. The trinuclear complex [(η3-C3H5)Ni(N2C5H7)2]2Ni is centrosymmetric with the central Ni(1) atom bonded to four pyrazolyl nitrogen atoms in square-planar fashion. The outer Ni(2) atom is bonded to two pyrazolyl nitrogens and to an allyl group and also has square-planar coordination geometry. Important bond distances in this complex are: Ni(1)—N, 1.897(1) and 1.901(1), Ni(2)—N, 1.908(2) and 1.912(2), Ni(2)—C, 1.97(l)–2.022(3) Å.

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Crystal chemistry of high-Tc superconductors

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100178720 ◽

1990 ◽

Vol 48 (4) ◽

pp. 1118-1119

Author(s):

Maryvonne Hervieu

Keyword(s):

Oxygen Deficiency ◽

Large Family ◽

Copper Oxides ◽

High Tc Superconductors ◽

High Tc ◽

Single Mechanism ◽

Square Planar ◽

History Of ◽

Bismuth Cuprates ◽

New Compounds

Four years after the discovery of superconductivity at high temperature in the Ba-La-Cu-O system, more than thirty new compounds have been synthesized, which can be classified in six series of copper oxides: La2CuO4 - type oxides, bismuth cuprates, YBa2Cu3O7 family, thallium cuprates, lead cuprates and Nd2CuO4 - type oxides. Despite their quite different specific natures, close relationships allow their structures to be simply described through a single mechanism. The fifth first families can indeed be described as intergrowths of multiple oxygen deficient perovskite slabs with multiple rock salt-type slabs, according to the representation [ACuO3-x]m [AO]n.The n and m values are integer in the parent structures, n varying from 0 to 3 and m from 1 to 4; every member of this large family can thus be symbolized by [m,n]. The oxygen deficient character of the perovskite slabs involves the existence or the co-existence of several types of copper environment: octahedral, pyramidal and square planar.Both mechanisms, oxygen deficiency and intergrowth, are well known to give rise easily to nonstoichiometry phenomena. Numerous and various phenomena have actually been characterized in these cuprates, strongly depending on the thermal history of the samples.

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New Platinum (II) Ternary Complexes of Formamidine and Pyrophosphate: Synthesis, Characterization and DFT Calculations and In vitro Cytotoxicity

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207323666200218115700 ◽

2020 ◽

Vol 23 (7) ◽

pp. 611-623

Author(s):

Ahmed A. Soliman ◽

Fawzy A. Attaby ◽

Othman I. Alajrawy ◽

Azza A.A. Abou-hussein ◽

Wolfgang Linert

Keyword(s):

Cell Line ◽

Cancer Cell ◽

Theoretical Calculations ◽

Thermal Analyses ◽

Cancer Cell Line ◽

Cellular Growth ◽

Planar Geometry ◽

Square Planar ◽

Vis Spectroscopy

Aim and Objective: Platinum (II) and platinum (IV) of pyrophosphate complexes have been prepared and characterized to discover their potential as antitumor drugs. This study was conducted to prepare and characterize new ternary platinum (II) complexes with formamidine and pyrophosphate as an antitumor candidate. Materials and Methods: The complexes have been characterized by mass, infrared, UV-Vis. spectroscopy, elemental analysis, magnetic susceptibility, thermal analyses, and theoretical calculations. They have been tested for their cytotoxicity, which was carried out using the fastcolorimetric assay for cellular growth and survival against MCF-7 (breast cancer cell line), HCT- 116 (colon carcinoma cell line), and HepG-2 (hepatocellular cancer cell line). Results: All complexes are diamagnetic, and the electronic spectral data displayed the bands due to square planar Pt(II) complexes. The optimized complexes structures (1-4) indicated a distorted square planar geometry where O-Pt-O and N-Pt-N bond angles were 82.04°-96.44°, respectively. Conclusion: The complexes showed noticeable cytotoxicity and are considered as promising antitumor candidates for further applications.

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Structure of the complexes of ethylenediphosphinetetraacetic acid in solution

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19850445 ◽

1985 ◽

Vol 50 (2) ◽

pp. 445-453 ◽

Cited By ~ 2

Author(s):

Jana Podlahová ◽

Josef Šilha ◽

Jaroslav Podlaha

Keyword(s):

Metal Ion ◽

Carboxyl Groups ◽

Complex Solution ◽

Square Planar ◽

Weak Complexes ◽

Carboxylic Groups ◽

Uv Visible ◽

The Stability ◽

Tetrahedral Complexes ◽

Free Carboxyl

Ethylenediphosphinetetraacetic acid is bonded to metal ions in aqueous solutions in four ways, depending on the type of metal ion: 1) through an ionic bond of the carboxylic groups to form weak complexes with a metal:ligand ratio of 1 : 1 (Ca(II), Mn(II), Zn(II), Pb(II), La(III)); 2) through type 1) bond with contributions from weak interaction with the phosphorus (Cd(II)); 3) through coordination of the ligand as a monodentate P-donor with the free carboxyl groups with formation of 2 : 1 and 1 : 1 complexes (Cu(I), Ag(I)); 4) through formation of square planar or, for Hg(II), tetrahedral complexes with a ratio of 1 : 2 with the ligand as a bidentate PP-donor with the free carboxyl groups (Fe(II), Co(II), Ni(II), Pd(II), Pt(II)). On acidification of the complex solution, the first two protons are bonded to the carboxyl groups. The behaviour during further protonation depends on the type of complex: in complexes of types 1) and 2) phosphorus is protonated and the complex dissociates; in complexes of types 3) and 4) the free carboxyl groups are protonated and the phosphorus-metal bond remains intact. The results are based on correlation of the stability constants, UV-visible, infrared, 1H and 31P NMR spectra and magnetic susceptibilities of the complexes in aqueous solution.

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Interaction of ditertiary phosphines with phenyl- and 1-naphthyldithiocarbamatonickel(II)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19851383 ◽

1985 ◽

Vol 50 (6) ◽

pp. 1383-1390

Author(s):

Aref A. M. Aly ◽

Ahmed A. Mohamed ◽

Mahmoud A. Mousa ◽

Mohamed El-Shabasy

Keyword(s):

Thermal Analysis ◽

Powder Diffraction ◽

Spin Structure ◽

Magnetic Measurements ◽

Mixed Ligand ◽

Mixed Ligand Complexes ◽

X Ray ◽

Square Planar

The synthesis of the following mixed ligand complexes is reported: [Ni(phdtc)2(dpm)2], [Ni(phdtc)2(dpe)2], [Ni(phdtc)2(dpp)3], [Ni(1-naphdtc)2(dpm)2], [Ni(1-naphdtc)2], and [Ni(1-naphdtc)2(dpp)2], where phdtc = PhNHCSS-, 1-naphdtc = 1-NaPhNHCSS-, dpm = Ph2PCH2PPh2, dpe = Ph2P(CH2)2PPh2, and dpp = Ph2P(CH2)3PPh2. The complexes are characterised by microanalysis, IR and UV-Vis spectra, magnetic measurements, conductivity, X-ray powder diffraction, and thermal analysis. All the mixed ligand complexes are diamagnetic, and thus a square-planar or square-pyramidal (low-spin) structure was proposed for the present complexes.

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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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Effect of the number of arms on the mechanical properties of a star-shaped cyclic olefin copolymer

Polymer Chemistry ◽

10.1039/c9py01186b ◽

2019 ◽

Vol 10 (41) ◽

pp. 5578-5583 ◽

Cited By ~ 1

Author(s):

Takumitsu Kida ◽

Ryo Tanaka ◽

Koh-hei Nitta ◽

Takeshi Shiono

Keyword(s):

Mechanical Properties ◽

Thermal Properties ◽

Physical Properties ◽

Secondary Amine ◽

Aggregation Number ◽

Drastic Change ◽

Cyclic Olefin Copolymer ◽

Cyclic Olefin

The increase of aggregation number in a star-shaped cyclic olefin copolymer was succeeded by using a triazine-based secondary amine, which caused a drastic change in physical properties without changing the thermal properties.

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