Effects of Metal Coordination Geometry on Stabilization of Human Telomeric Quadruplex DNA by Square-Planar and Square-Pyramidal Metal Complexes

2008 ◽  
Vol 47 (24) ◽  
pp. 11910-11919 ◽  
Author(s):  
Anna Arola-Arnal ◽  
Jordi Benet-Buchholz ◽  
Stephen Neidle ◽  
Ramón Vilar
Keyword(s):  
Metal Complexes ◽  
Metal Coordination ◽  
Coordination Geometry ◽  
Quadruplex Dna ◽  
Square Planar

Übergangsmetallkomplexe mit Schwefelliganden, LXXVI Redox- und Additionsreaktionen von Nickelkomplexen mehrzähniger Thioether-Thiolat-Liganden. Röntgenstrukturanalysen von (NMe4)2[Ni(′S2′)2] und [Ni(′S4 – C3′)(PMe3)] / Transition Metal Complexes with Sulfur Ligands, LXXVI Redox and Addition Reactions of Nickel Complexes with Multidentate Thioether-Thiolato Ligands. X-Ray Structure Determinations of (NMe4)2[Ni(′S2′)2] and [Ni(′S4–C3′)(PMe3)]

1991 ◽  
Vol 46 (12) ◽  
pp. 1601-1608 ◽  
Author(s):  
Dieter Sellmann ◽  
Stefan Fünfgelder ◽  
Falk Knoch ◽  
Matthias Moll
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Structure Analysis ◽  
Transition Metal Complexes ◽  
Nickel Complexes ◽  
Addition Reactions ◽  
Coordination Geometry ◽  
X Ray ◽  
Square Planar ◽  
Structure Determinations

In order to elucidate specific properties of nickel sulfur complexes, redox and addition-elimination reactions of [Ni(′OS4')]2, [Ni(′NHS4')]2, [Ni(′S5')], [Ni('S4—C5')], and [Ni('S4—C3')] were investigated ('OS4′ 2' = 2,2'-bis(2-mercaptophenylthio)diethylether(2—), 'NHS4'2- = 2,2'-bis(2-mercaptophenylthio)diethylamine(2—), 'S5'2- = 2,2'-bis(2-mercaptophenylthio)diethylsulfide(2—), 'S4-C5'2- = 1,5-bis(2-mercaptophenylthio)pentane(2—), 'S4—C3'2- = 1,3-bis(2-mercaptophenylthio)propane(2—)).Cyclovoltammetry proves the complexes to be redox inactive between —1.4 and +0.8 V vs. NHE. Above +0.8 V the complexes are irreversibly oxidized, below —1,4 V desalkylation takes place and [Ni(′S,′)2]2- is formed. An X-ray structure analysis was carried out of (NMe4)2[Ni(′S2')2], which shows a planar anion with the Ni center in a nearly perfect square planar coordination. Distances and angles are practically identical to those in the [Ni(′S2')2-] monoanion.The complexes coordinate only phosphines as coligands, but thioether donors simultaneously decoordinate and, dependant of reaction temperature, mono- or trisphosphine complexes are formed. [Ni(′S4—C3')(PMe3)] was characterized by X-ray structure analysis and exhibits a square pyramidal coordination geometry.

Using cluster analysis to study transition-metal geometries: four-coordinate complexes with two salicylaldiminato or related ligands

2007 ◽  
Vol 63 (4) ◽  
pp. 612-620 ◽  
Author(s):  
Andrew Parkin ◽  
Gordon Barr ◽  
Anna Collins ◽  
Wei Dong ◽  
Christopher J. Gilmore ◽  
...  
Keyword(s):  
Cluster Analysis ◽  
Transition Metal ◽  
Metal Complexes ◽  
Prior Knowledge ◽  
Transition Metal Complexes ◽  
Cambridge Structural Database ◽  
Metal Coordination ◽  
Coordination Geometry ◽  
Geometric Similarity ◽  
Structural Database

Cluster analysis is shown to be an effective method to analyse and classify metal coordination geometry in a very large number of four-coordinate bis-salicylaldimato (or bis-β-iminoketonate) transition-metal complexes available in the Cambridge Structural Database. The methods described require no prior knowledge of chemistry to be input; retrieved structures are automatically clustered into groups based purely on the geometric similarity of the fragments and these groupings can then be interpreted by the structural chemist.

scholarly journals Self-Assembled M2L4 Nanocapsules: Synthesis, Structure and Host-Guest Recognition Toward Square Planar Metal Complexes

Materials ◽  
2014 ◽  
Vol 7 (1) ◽  
pp. 287-301 ◽  
Author(s):  
Christophe Desmarets ◽  
Thierry Ducarre ◽  
Marie Rager ◽  
Geoffrey Gontard ◽  
Hani Amouri
Keyword(s):  
Metal Complexes ◽  
Square Planar ◽  
Self Assembled

CO2 reduction catalysis by tunable square-planar transition-metal complexes: a theoretical investigation using nitrogen-substituted carbon nanotube models

2017 ◽  
Vol 19 (43) ◽  
pp. 29068-29076 ◽  
Author(s):  
Yu-Te Chan ◽  
Ming-Kang Tsai
Keyword(s):  
Density Functional Theory ◽  
Carbon Nanotube ◽  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Density Functional ◽  
Co2 Reduction ◽  
Functional Theory ◽  
Square Planar ◽  
Planar Transition

The CO2 reduction capabilities of transition-metal-chelated nitrogen-substituted carbon nanotube models (TM-4N2v-CNT, TM = Fe, Ru, Os, Co, Rh, Ir, Ni, Pt or Cu) are characterized by density functional theory.

scholarly journals [μ2-N2,N2′-Bis(3-methoxy-2-oxidobenzylidene)benzene-1,3-dicarbohydrazidato]bis[pyridinecopper(II)]

2013 ◽  
Vol 69 (12) ◽  
pp. m658-m658
Author(s):  
Hai-Bin Tong ◽  
Zi-Jing Xiao
Keyword(s):  
Title Complex ◽  
Coordination Geometry ◽  
Square Planar ◽  
The Mean

In the centrosymmetric dinuclear title complex, [Cu2(C24H18N4O6)(C5H5N)2], the CuIIions is tetracoordinated by two O-atoms and one N-donor of the bridging terephthalohydrazonate ligand and by one pyridine N atom, resulting in a nearly square-planar N2O2coordination geometry with the CuIIion 0.044 (2) Å out of the mean plane (r.m.s. deviation of 0.0675 Å) of the coordinating atoms.

scholarly journals (2,2′-Bipyridine-κ2 N,N′)(pyridine-2,6-dicarboxylato-κ2 N,O)palladium(II) monohydrate

IUCrData ◽  
2019 ◽  
Vol 4 (12) ◽  
Author(s):  
Kwang Ha
Keyword(s):  
Hydrogen Bonds ◽  
Water Molecule ◽  
Title Compound ◽  
Coordination Geometry ◽  
Intermolecular Hydrogen Bonds ◽  
Complex Molecules ◽  
Solvent Water Molecule ◽  
Solvent Water ◽  
Square Planar ◽  
Bipyridine Ligand

In the title compound, [Pd(C7H3NO4)(C10H8N2)]·H2O, the PdII cation is four-coordinated in a distorted square-planar coordination geometry defined by the two N atoms of the 2,2′-bipyridine ligand, one O atom and one N atom from the pyridine-2,6-dicarboxylate anion. The complex and solvent water molecule are linked by intermolecular hydrogen bonds. In the crystal, the complex molecules are stacked in columns along the a axis.

scholarly journals Comparison of molecular structures of cis-bis[8-(dimethylphosphanyl)quinoline]nickel(II) and -platinum(II) complex cations

2020 ◽  
Vol 76 (12) ◽  
pp. 1813-1817
Author(s):  
Masatoshi Mori ◽  
Takayoshi Suzuki
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Steric Hindrance ◽  
Molecular Structures ◽  
Coordination Geometry ◽  
Donor Group ◽  
Bending Deformation ◽  
Bond Lengths ◽  
Square Planar ◽  
Chelate Ligands

The crystal structures of the complexes (SP-4-2)-cis-bis[8-(dimethylphosphanyl)quinoline-κ2 N,P]nickel(II) bis(perchlorate) nitromethane monosolvate, [Ni(C11H12NP)2](ClO4)2·CH3NO2 (1), and (SP-4-2)-cis-bis[8-(dimethylphosphanyl)quinoline-κ2 N,P]platinum(II) bis(tetrafluoroborate) acetonitrile monosolvate, [Pt(C11H12NP)2](BF4)2·C2H3N (2), are reported. In both complex cations, two phosphanylquinolines act as bidentate P,N-donating chelate ligands and form the mutually cis configuration in the square-planar coordination geometry. The strong trans influence of the dimethylphosphanyl donor group is confirmed by the Ni—N bond lengths in 1, 1.970 (2) and 1.982 (2) Å and, the Pt—N bond lengths of 2, 2.123 (4) and 2.132 (4) Å, which are relatively long as compared to those in the analogous 8-(diphenylphosphanyl)quinoline complexes. Mutually cis-positioned quinoline donor groups would give a severe steric hindrance between their ortho-H atoms. In order to reduce such a steric congestion, the NiII complex in 1 shows a tetrahedral distortion of the coordination geometry, as parameterized by τ4 = 0.199 (1)°, while the PtII complex in 2 exhibits a typical square-planar coordination geometry [τ4 = 0.014 (1)°] with a large bending deformation of the ideally planar Me2Pqn chelate planes. In the crystal structure of 2, three F atoms of one of the BF4 − anions are disordered over two sets of positions with refined occupancies of 0.573 (10) and 0.427 (10).

scholarly journals Synthesis and Spectroscopic Characterization for Some Metal ion Complexes with 2-Hydroxy-3-((5-Mercapto-1,3,4-Thiadiazol-2-yl)Diazenyl)-1-Naphthaldehyde

2016 ◽  
Vol 13 (2) ◽  
pp. 105-114
Author(s):  
Baghdad Science Journal
Keyword(s):  
Metal Complexes ◽  
Metal Ion ◽  
Mass Spectra ◽  
Spectroscopic Characterization ◽  
Bidentate Ligand ◽  
Molar Ratio ◽  
Theoretical Treatment ◽  
Spectroscopic Techniques ◽  
Metal Ion Complexes ◽  
Square Planar

New metal ion complexes were synthesized with the general formula; K[PtLCl4], [ReLCl4] and K[ML(Cl)2] where M = Pd(II), Cd(II), Zn(II) and Hg(II), from the Azo ligand (HL) [2-Hydroxy-3-((5-mercapto-1,3,4-thiadiazol-2-yl)diazenyl)-1-naphth aldehyde] (HL) the ligand was synthesized from (2-hydroxy-1-naphthaldehyde) and (5-amino-1,3,4-thiadiazole-2-thiol). The ligand and its metal complexes are characterized by phisco- chemical spectroscopic techniques (FT.IR, UV-Vis and Mass spectra, elemental analysis, molar conductivity, Atomic Absorption, Chloride contain and magnetic susceptibility). The spectral data suggest that the (HL) behaves as a bidentate ligand in all complexes. These studies revealed tetrahedral geometries for all metal complexes, except square planar for Pd(II) complex and except octahedral geometry for Pt(IV) and Re(V) complexes. The study of complexes formation via molar ratio of (M:L) as (1:1). Theoretical treatment of this ligand and its metal complexes in gas phase using Hyper chem.8 was preformed.

scholarly journals Di-μ-chlorido-bis{[2-(di-tert-butylphosphanyl)biphenyl-3-yl-κ2C3,P]palladium(II)} dichloromethane disolvate

2013 ◽  
Vol 69 (2) ◽  
pp. m86-m86 ◽  
Author(s):  
Cedric W. Holzapfel ◽  
Bernard Omondi
Keyword(s):  
Palladium Complex ◽  
Solvent Molecule ◽  
Membered Ring ◽  
The Other ◽  
Coordination Geometry ◽  
Inversion Center ◽  
Asymmetric Unit ◽  
Coordination Sites ◽  
Square Planar ◽  
Cl Atoms

The asymmetric unit of the title compound, [Pd2Cl2(C20H26P)2]·2CH2Cl2, contains one half-molecule of the palladium complex and a dichloromethane solvent molecule. In the complex, two PdIIatoms are bridged by two Cl atoms, with the other two coordination sites occupied by a C atom of the biphenyl system and a P atom, resulting in a distorted square-planar coordination geometry of the PdIIatom and a cyclometallated four-membered ring. The Pd2Cl2unit is located about an inversion center. The planes of the rings of the biphenyl system make a dihedral angle of 66.36 (11)°.

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