Preparation and Characterization of Cobalt(III) Complexes Containing 1,1′-Bis(diphenylphosphino)ferrocene (dppf) or 1,1′-Bis(dimethylphosphino)ferrocene (dmpf) as a Bidentate Ligand, and Molecular Structures of [Co(acac)2(dmpf)]B(C6H5)4and [Co(dtc)2(dmpf)]B(C6H5)4(acac = 2,4-pentanedionate ion, dtc = dimethyldithiocarbamate ion)

1992 ◽  
Vol 65 (8) ◽  
pp. 2037-2044 ◽  
Author(s):  
Masahiro Adachi ◽  
Masakazu Kita ◽  
Kazuo Kashiwabara ◽  
Junnosuke Fujita ◽  
Naoyuki Iitaka ◽  
...  
Keyword(s):  
Bidentate Ligand ◽  
Molecular Structures

A Solvent-Dependent and Electrochemically Controlled Self-Assembling/Disassembling System

2003 ◽  
Vol 68 (9) ◽  
pp. 1647-1662 ◽  
Author(s):  
Valeria Amendola ◽  
Massimo Boiocchi ◽  
Yuri Diaz Fernandez ◽  
Carlo Mangano ◽  
Piersandro Pallavicini
Keyword(s):  
Equilibrium Mixture ◽  
Bidentate Ligand ◽  
Molecular Structures ◽  
The Self ◽  
Molar Ratio ◽  
Crystal And Molecular Structures ◽  
Self Assembling ◽  
Irreversible Oxidation ◽  
Irreversible Reduction ◽  
Metal Ligand

The bis-bidentate ligand R,S-1,2-diphenyl-N,N'-bis(2-quinolinemethylidene)ethane-1,2-diamine (ligand 4), containing two (iminomethyl)quinoline moieties separated by a cis-1,2-diphenylethylene spacer, forms stable complexes with both CuI and CuII. With CuII, the monomeric 1:1 complex [CuII(4)]2+ is obtained both in CH3CN and CH2Cl2. With CuI and overall 1:1 metal/ligand molar ratio, an equilibrium mixture is obtained in CH3CN, consisting of [CuI(4)2]+, [CuI2(4)2]2+ and [CuI2(4)(CH3CN)4]2+. The preponderant species is the two-metal one-ligand "open" complex [CuI2(4)(CH3CN)4]2+, in which each Cu+ cation is coordinated in a tetrahedral fashion by one (iminomethyl)quinoline unit and by two CH3CN molecules. Precipitation from the equilibrium mixture yields only crystals of [CuI2(4)(CH3CN)4](ClO4)2·2CH3CN, whose crystal and molecular structures have been determined. On the other hand, in the poorly coordinating CH2Cl2 solvent, only the dimeric helical [CuI2(4)2]2+ complex is obtained, when the overall metal/ligand 1:1 molar ratio is chosen. Addition of large quantities of acetonitrile to solutions of [CuI2(4)2]2+ in dichlorometane results in the formation of [CuI2(4)(CH3CN)4]2+, i.e. in the solvent-driven disassembling of the CuI helicate. While electrochemistry in CH3CN is poorly defined due to the presence of more than one CuI species, cyclic voltammetry experiments carried out in CH2Cl2 revealed a well defined behavior, with irreversible oxidation of [CuI2(4)2]2+ and irreversible reduction of [CuII(4)]2+ taking place at separate potentials (∆E ≈ 700 mV). Irreversibility and separation of the redox events are due to the self-assembling and disassembling processes following the reduction and oxidation, respectively.

scholarly journals Crystal structure of a mononuclear RuIIcomplex with a back-to-back terpyridine ligand: [RuCl(bpy)(tpy–tpy)]+

2015 ◽  
Vol 71 (9) ◽  
pp. 1017-1021 ◽  
Author(s):  
Francisca N. Rein ◽  
Weizhong Chen ◽  
Brian L. Scott ◽  
Reginaldo C. Rocha
Keyword(s):  
Crystal Structure ◽  
Crystal Packing ◽  
Bidentate Ligand ◽  
Octahedral Geometry ◽  
Distorted Octahedral Geometry ◽  
Stacking Interactions ◽  
Bite Angle ◽  
Distorted Octahedral ◽  
The Mean

We report the structural characterization of [6′,6′′-bis(pyridin-2-yl)-2,2′:4′,4′′:2′′,2′′′-quaterpyridine](2,2′-bipyridine)chloridoruthenium(II) hexafluoridophosphate, [RuCl(C10H8N2)(C30H20N6)]PF6, which contains the bidentate ligand 2,2′-bipyridine (bpy) and the tridendate ligand 6′,6′′-bis(pyridin-2-yl)-2,2′:4′,4′′:2′′,2′′′-quaterpyridine (tpy–tpy). The [RuCl(bpy)(tpy–tpy)]+monocation has a distorted octahedral geometry at the central RuIIion due to the restricted bite angle [159.32 (16)°] of the tridendate ligand. The Ru-bound tpy and bpy moieties are nearly planar and essentially perpendicular to each other with a dihedral angle of 89.78 (11)° between the least-squares planes. The lengths of the two Ru—N bonds for bpy are 2.028 (4) and 2.075 (4) Å, with the shorter bond being opposite to Ru—Cl. For tpy–tpy, the mean Ru—N distance involving the outer N atomstransto each other is 2.053 (8) Å, whereas the length of the much shorter bond involving the central N atom is 1.936 (4) Å. The Ru—Cl distance is 2.3982 (16) Å. The free uncoordinated moiety of tpy–tpy adopts atrans,transconformation about the interannular C—C bonds, with adjacent pyridyl rings being only approximately coplanar. The crystal packing shows significant π–π stacking interactions based on tpy–tpy. The crystal structure reported here is the first for a tpy–tpy complex of ruthenium.

Synthesis and characterization of 2-(n-alkylamino)-1,4-napthoquinone: Molecular structures of ethyl and hexyl derivatives

2014 ◽  
Vol 1075 ◽  
pp. 345-351 ◽  
Author(s):  
Rishikesh Patil ◽  
Dattatray Chadar ◽  
Dinkar Chaudhari ◽  
Justin Peter ◽  
Milind Nikalje ◽  
...  
Keyword(s):  
Molecular Structures ◽  
Synthesis And Characterization

Synthesis and Characterization of Some Functional Luminol Derivatives with Aromatic Substituted Groups

2011 ◽  
Vol 197-198 ◽  
pp. 606-609 ◽  
Author(s):  
Ti Feng Jiao ◽  
Yuan Yuan Xing ◽  
Jing Xin Zhou ◽  
Wei Wang
Keyword(s):  
Molecular Structure ◽  
Thermal Stability ◽  
Molecular Structures ◽  
Synthesis And Characterization ◽  
Functional Material ◽  
Aromatic Substituent ◽  
The Difference ◽  
Imide Group ◽  
Thermal Stability Of

Some functional luminol derivatives with aromatic substituted groups have been designed and synthesized from the reaction of the corresponding aromatic acyl chloride precursors with luminol. It has been found that depending on the size of aromatic groups, the formed luminol derivatives showed different properties, indicating distinct regulation of molecular skeletons. UV and IR data confirmed commonly the formation of imide group as well as aromatic segment in molecular structures. Thermal analysis showed that the thermal stability of luminol derivatives with p-phthaloyl segment was the highest in those derivatives. The difference of thermal stability is mainly attributed to the formation of imide group and aromatic substituent groups in molecular structure. The present results have demonstrated that the special properties of luminol derivatives can be turned by modifying molecular structures of objective compounds with proper substituted groups, which show potential application in functional material field and ECL sensor.

Structural characterization of soil organic matter individual fractions (fulvic acids, humic acids and humins) in relation to potential sorption of organic contaminants 

2021 ◽  
Author(s):  
Aleksandra Ukalska-Jaruga ◽  
Romualda Bejger ◽  
Guillaume Debaene ◽  
Bozena Smreczak
Keyword(s):  
Molecular Weight ◽  
Humic Substances ◽  
Organic Contaminants ◽  
Particle Diameter ◽  
Fulvic Acids ◽  
Molecular Structures ◽  
Sorption Properties ◽  
Binding Potential ◽  
Aliphatic Chains

<p>The objective of this paper was to investigate the molecular characterization of individual humic substances ( fulvic acids-FAs, humic ascids-HAs, and humins-HNs), which are the most reactive soil components and exhibit high sorption capacity in relation to various groups of organic contaminants. A wide spectrum of spectroscopic (UV-VIS, VIS-nearIR), as well as electrochemical (zeta potential, particle size diameter, polidyspersity index), methods were applied to find the relevant differences in the behavior, formation, composition and sorption properties of HS fractions derived from various mineral soils.</p><p>Soil material (n = 30) used for the study were sampled from the surface layer (0–30 cm) of agricultural soils. FAs and HAs were isolated by sequential extraction in alkaline and acidic solutions, according to the International Humic Substances Society method, while HNs was determined in the soil residue (after FAs and HAs extraction) by mineral fraction digestion using a 0.1M HCL/0.3M HF mixture and DMSO.</p><p>Our study showed that significant differences in the molecular structures of FAs, HAs and HNs occurred. Optical analysis confirmed the lower molecular weight of FAs with high amount of lignin-like compounds and the higher weighted aliphatic–aromatic structure of HAs. The HNs were characterized by a very pronounced and strong condensed structure associated with the highest molecular weight. HAs and HNs molecules exhibited an abundance of acidic, phenolic and amine functional groups at the aromatic ring and aliphatic chains, while FAs mainly showed the presence of methyl, methylene, ethenyl and carboxyl reactive groups. HS was characterized by high polydispersity related with their structure. FAs were characterized by ellipsoidal shape as being associated to the long aliphatic chains, while HAs and HNs revealed a smaller particle diameter and a more spherical shape caused by the higher intermolecular forcing between the particles.  </p><p>The observed trends directly indicate that individual HS fractions differ in behavior, formation, composition and sorption properties, which reflects their binding potential to different group of organic contaminants, but the general properties of individual fractions are similar and do not depend on the type of soil.</p><p><em>Acknowledgement: The studies were supported from the National Science Centre project No. 2018/29/N/ST10/01320 “Analysis of the fractional composition and sorption properties of humic substances in relation to various groups of organic contaminants”</em></p>

scholarly journals Water-Soluble Bismuth(III) Polynuclear Tyrosinehydroximate Metallamacrocyclic Complex: Structural Parallels to Lanthanide Metallacrowns

Molecules ◽  
2020 ◽  
Vol 25 (19) ◽  
pp. 4379
Author(s):  
Marina A. Katkova ◽  
Grigory Y. Zhigulin ◽  
Roman V. Rumyantcev ◽  
Galina S. Zabrodina ◽  
Vladimir R. Shayapov ◽  
...  
Keyword(s):  
Electronic Structures ◽  
Structural Parameters ◽  
Molecular Structures ◽  
Water Soluble ◽  
Thermochromic Properties ◽  
Donor Acceptor ◽  
Coordination Ability ◽  
Synthetic Routes ◽  
Complex Structural

Recently there has been a great deal of interest and associated research into aspects of the coordination chemistry of lanthanides and bismuth—elements that show intriguing common features. This work focuses on the synthesis and characterization of a novel bismuth(III) polynuclear metallamacrocyclic complex derived from aminohydroxamic acid, in order to compare the coordination ability of Bi3+ with the similarly sized La3+ ions. A polynuclear tyrosinehydroximate Bi(OH)[15-MCCu(II)Tyrha-5](NO3)2 (1) was obtained according to the synthetic routes previously described for water-soluble Ln(III)-Cu(II) 15-MC-5 metallacrowns. Correlations between structural parameters of Bi(III) and Ln(III) complexes were analyzed. DFT calculations confirmed the similarity between molecular structures of the model bismuth(III) and lanthanum(III) tyrosinehydroximate 15-metallacrowns-5. Analysis of the electronic structures revealed, however, stronger donor-acceptor interactions between the central ion and the metallamacrocycle in the case of the lanthanum analogue. Thermochromic properties of 1 were studied.

Synthesis and Characterization of Co(II) Coordination Polymer with a Flexible Bidentate Ligand

2019 ◽  
Vol 64 (7) ◽  
pp. 1084-1088
Author(s):  
Mehdi Khalaj ◽  
Arash Lalegani ◽  
Krzysztof Lyczko ◽  
Janusz Lipkowski
Keyword(s):  
Coordination Polymer ◽  
Bidentate Ligand ◽  
Synthesis And Characterization
Sign in / Sign up

Export Citation Format

Share Document