New Macrocyclic Complexes Derived From Cobalt(III) Cage Complexes

1994 ◽  
Vol 47 (3) ◽  
pp. 529 ◽  
Author(s):  
II Creaser ◽  
T Komorita ◽  
AM Sargeson ◽  
AC Willis ◽  
K Yamanari
Keyword(s):  
Aqueous Solution ◽  
Strain Energy ◽  
Macrocyclic Ligand ◽  
Zinc Powder ◽  
Crystallographic Analysis ◽  
X Ray ◽  
Alkyl Complexes ◽  
Nitrogen Donor ◽  
Asymmetric Nitrogen

The synthesis and partial characterization of several green complexes, derived from the products of the reactions between [Co(Cl2-sar)]3+ (Cl2-sar = 1,8-dichloro-3,6,10,13,16,19- hexaazabicyclo [6.6.6] icosane ) and zinc powder in water, are described. Most of the complexes appear to have [CoCl2(N4)] chromophores , where N4 denotes the tetraaza macrocyclic ligand , 6,13-dimethylene-1,4,8,11-tetraazacyclotetradecane (L1). For trans-[CoCl2(L1)]+, three isomers due to different configurations about the asymmetric nitrogen donor centres were obtained and characterized by the electronic absorption and 13C n.m.r. spectra. Their stereochemistry is discussed and compared with that of 1,4,8,11-tetraazacyclotetradecane on the basis of strain energy minimized calculations. A trans-[CoCl2(H2L2)]3+ complex containing a related macrocycle with a pendant ethane-1,2-diamine arm [H2L2+, 6-(4-ammonio-2-azoniabutyl)-13-methylene-1,4,8,11-tetraazacyclotetradecane] was also isolated and characterized by X-ray crystallographic analysis. All these molecules are derived from the decomposition of zinc alkyl complexes formed by oxidative addition of zinc to the parent [CoII(Cl2-sar)]2+ ion in aqueous solution.

Selenium coronands. A novel conformational pair

1988 ◽  
Vol 66 (11) ◽  
pp. 2956-2958 ◽  
Author(s):  
B. Mario Pinto ◽  
Blair D. Johnston ◽  
Raymond J. Batchelor ◽  
Frederick W. B. Einstein ◽  
Ian D. Gay
Keyword(s):  
Nmr Spectra ◽  
Crystallographic Analysis ◽  
The Novel ◽  
Torsion Angles ◽  
X Ray ◽  
Structure Formula ◽  
Independent Molecules ◽  
Similar Conformation ◽  
C Nmr

The synthesis and characterization of the novel selenium coronands, 1,3,7,9-tetraselenacyclododecane 1a, 1,3,7,9,13,15-hexaselenacyclooctadecane 2a, the corresponding β-gem-dimethyl derivatives 1b, 2b, and 1,5,9,13-tetraselenacyclohexadecane 3, and 1,5,9,13,17,21-hexaselenacyclotetracosane 4 are described. X-ray crystallographic analysis of 1a reveals three independent molecules that exist in two distinct conformations, one molecule having approximate two-fold symmetry together with two molecules (of similar conformation) each having crystallographic [Formula: see text] symmetry. The conformations are denoted as [3333] or [66]. Whereas one resembles that of cyclododecane and tetrathia-12-crown-4 with respect to torsion angles, the other resembles that of tetraoxa-12-crown-4. The solid state CP-MAS 77Se and 13C nmr spectra are interpreted in light of the crystallographic information. Crystal structure: formula Se4C8H16; fw = 428.05; monoclinic, P21/c; Z = 8; a = 15.823(2) Å, b = 5.534(1) Å, c = 27.962(5) Å, β = 92.26(1)°; V = 2446.6 Å3; T = 200 K; R = 0.027 for 2162 observed data (I ≥ 2.5σ(I)).

Structural and IR-spectroscopic characterization of magnesium acesulfamate

2016 ◽  
Vol 71 (1) ◽  
pp. 51-55 ◽  
Author(s):  
Oscar E. Piro ◽  
Gustavo A. Echeverría ◽  
Beatriz S. Parajón-Costa ◽  
Enrique J. Baran
Keyword(s):  
Crystal Structure ◽  
Aqueous Solution ◽  
Elemental Analysis ◽  
Spectroscopic Characterization ◽  
Magnesium Carbonate ◽  
X Ray Diffraction ◽  
Triclinic Space Group ◽  
X Ray ◽  
Ir Spectroscopic

AbstractMagnesium acesulfamate, Mg(C4H4NO4S)2·6H2O, was prepared by the reaction of acesulfamic acid and magnesium carbonate in aqueous solution, and characterized by elemental analysis. Its crystal structure was determined by single crystal X-ray diffraction methods. The substance crystallizes in the triclinic space group P1̅ with one molecule per unit cell. The FTIR spectrum of the compound was also recorded and is briefly discussed. Some comparisons with other simple acesulfamate and saccharinate salts are also made.

Preparation and Characterization of Carbon Nanotubes/Al2O3 Inorganic Hybrid Material - A Bio-Inspired Poly(Dopamine) Approach

2018 ◽  
Vol 54 ◽  
pp. 127-135
Author(s):  
Wen Zhao ◽  
Wen Cai Wang ◽  
Yong Lai Lu ◽  
Li Qun Zhang
Keyword(s):  
Carbon Nanotubes ◽  
Aqueous Solution ◽  
Photoelectron Spectroscopy ◽  
Oxidative Polymerization ◽  
The Self ◽  
Liquid Phase Deposition ◽  
X Ray ◽  
Transmission Electron ◽  
Cnts Surface

Carbon nanotubes/alumina (CNTs/Al2O3) nanocomposites were prepared by the poly (dopamine) assisted chemical liquid phase deposition (CLPD). The poly (dopamine) layers were firstly coated on the CNTs surface uniformly by the self-oxidative polymerization of dopamine in mild aqueous solution and then the Al2O3 nanoparticles formed on the poly (dopamine) coated CNTs surface by the CLPD. The hydrophilic poly (dopamine) layers on the CNTs surface can improve the dispersion of CNTs in aqueous solution. Moreover, it can be used as a key linker between the CNTs and Al2O3 because of the nitrogen-containing group in poly (dopamine) could coordinate with Al3+ ions. The as-prepared poly (dopamine) coated CNTs and CNTs/Al2O3 nanohybrids were characterized by X-ray photoelectron spectroscopy (XPS), X-radial diffractometer (XRD) and high resolution transmission electron microscopy (HRTEM). These results showed that the poly (dopamine) layers were coated on the surface of CNTs uniformly, and the Al2O3 nanoparticles embellished with the poly (dopamine) coated CNTs surface. Compared with pristine NR composites, the thermal conductivity of the as-prepared NR/CNTs@Al2O3 composites increased 17%.

scholarly journals The Synthesis and Effect of Silver Nanoparticles on the Adsorption of Cu2+ from Aqueous Solutions

2020 ◽  
Vol 10 (14) ◽  
pp. 4840
Author(s):  
Ghadah M. Al-Senani ◽  
Nada Al-Kadhi
Keyword(s):  
Aqueous Solution ◽  
Freundlich Isotherm ◽  
Spherical Particles ◽  
Convolvulus Arvensis ◽  
X Ray ◽  
Nanoparticle Surface ◽  
Before And After ◽  
Adsorption Processes ◽  
Sem Analyses

The adsorption of Cu2+ ions from an aqueous solution using AgNPs synthesized from Convolvulus arvensis leaf extract was investigated. The characterization of AgNPs was investigated before and after the adsorption of Cu2+ ions via Fourier-transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDS), and scanning electron microscopy (SEM) analyses. The adsorbent contained various functional groups in addition to the AgNPs, which contributed to the Cu2+ ions adsorption. The silver nanoparticle surface consisted of spherical particles and deep pores, which adsorbed numerous Cu2+ ions. The influences of dosage, pH, and contact time on adsorption of 10 and 50 mg/L Cu2+ at 298 K, and initial Cu2+ concentrations at 298 and 323 K were studied. It was found that the highest percentage of Cu2+ ions adsorbed from an aqueous solution was 98.99%; the aqueous solution had 10 mg/L of Cu2+ ions and 0.2 g of AgNPs, at pH 12 and 298 K. A pseudo-second kinetics model offered the most accurate description of the process of adsorption. The process of Cu2+ adsorption more resembled a Langmuir rather than a Freundlich isotherm model, including chemical and physical mixed adsorption (mixed adsorption) processes, and was exothermic and spontaneous.

Characterization of the Acetonitrile Aqueous Solution/Vapor Interface by Liquid-Jet X-ray Photoelectron Spectroscopy

2014 ◽  
Vol 118 (50) ◽  
pp. 29378-29388 ◽  
Author(s):  
Kathryn A. Perrine ◽  
Marijke H. C. Van Spyk ◽  
Alexandria M. Margarella ◽  
Bernd Winter ◽  
Manfred Faubel ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Photoelectron Spectroscopy ◽  
Liquid Jet ◽  
Vapor Interface ◽  
X Ray

Structural Characterization of a Cage Ligand Fragmentation Reaction

1994 ◽  
Vol 47 (1) ◽  
pp. 181 ◽  
Author(s):  
JM Harrowfield ◽  
AM Sargeson ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Single Crystal ◽  
Structural Characterization ◽  
Room Temperature ◽  
Fragmentation Reaction ◽  
X Ray ◽  
Nitrogen Donor ◽  
Crystal Structural

The room temperature X-ray single-crystal structural characterization of a protonated copper(II) complex of a ligand artefact, L′, of L = N-Me6sar (described in an accompanying paper) is recorded, the new ligand L′ being generated formally by elimination of a CH2CH2 bridge between a pair of nitrogen donor atoms of L. The complex, [ ClCu (H2L′) (ClO4)3.2H2O, is orthorhombic, Pccn , a 22.528(7), b 10.544(3), c 13.748(6) Ǻ, Z = 4 formula units, R being 0.053 for 1133 independent 'observed' [I > 3σ(I)] reflections. The cation, containing five-coordinate square-pyramidal ClCuN4 copper, is disposed with the Cu- Cl bond [2.458(3)Ǻ] lying on a crystallographic 2 axis; Cu-N distances are 2.094(8) and 2.093(8)Ǻ.

Synthesis, characterization, and x-ray crystal structure of tris-isothiocyanato complexes of the yttrium(III) and europium(III) ions with a six-nitrogen-donor macrocyclic ligand

Polyhedron ◽  
1989 ◽  
Vol 8 (17) ◽  
pp. 2157-2167 ◽  
Author(s):  
G. Bomibieri ◽  
F. Benetollo ◽  
A. Polo ◽  
L. De Cola ◽  
W.T. Hawkins ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Macrocyclic Ligand ◽  
X Ray ◽  
Nitrogen Donor
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