Showing papers in "Polyhedron in 1997"

TL;DR: In this article, it was shown that 4-methyldibenzothiophene and 4,6-dimethyltibenzethiophene are the most appropriate compounds for investigations of candidate catalysts and reaction mechanisms for deep desulfurization.

TL;DR: In this paper, the authors highlight organometallic and clean surface model studies that offer realistic ways of understanding details of hydrodesulfurization, hydrodenitrogenation, and hydrodeoxygenation reactions as they occur on heterogeneous hydrotreating catalysts.

TL;DR: In this article, the authors present a survey of the state-of-the-art macrocyclic ligands in the literature, focusing on the following groups: donor, mixed donor, oxygen, and selenium.

TL;DR: In this paper, a study of the H+ −CrO42− system in 3.0 M KCl as ionic medium at 25°C by means of emf (glass electrode) and direct calorimetric measurements was conducted.

TL;DR: In this paper, the substituted sandwich-like bis(phthalocyaninato)lanthanide(III) complexes have been obtained by treating Ln(acac) 3 ·nH 2 O (Ln = Eu, Gd; acac = acetylacetonate) with dilithium phthalocyaninate or with corresponding disubstituted phthalonitriles in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU).

TL;DR: In this paper, a partial rearrangement of octa-silsesquioxanes, R8(SiO1.5)8 (1), was performed to give species of the type R10 (SiO 1.5 )10 (II) and D2d-R12(Si O 1.5 )12 (III).

TL;DR: In this article, the effects of different electron donor and acceptor groups on the 1 H NMR, electronic absorption and emission spectra were studied, and it was shown that the addition of calf thymus DNA into the complex solution results in increases for both emissive intensities and excited state lifetimes, and indicates that the electron group on L has no significant effect on the intercalation binding mode between DNA and the complexes.

TL;DR: In this paper, the binding of tetradentate ligands with two N and two O donor sites to copper(II) ion was investigated and it was shown that ligand geometry, steric bulk and electron donating effects of the ligand substituents are among the factors influencing the redox potentials of the complexes.

TL;DR: In this paper, the four thiosemicarbazones have been characterized by their melting points, as well as IR, electronic and NMR (1H, 13C) spectra.

TL;DR: In this paper, the N N stretch in copper(I) complexes shows a large shift to lower frequency from the free ligand value (ca 1400 cm−1) due to d(Cu) → π* (RaaiR′) back bonding.

TL;DR: In this article, three complexes of the formula [Zn(2,2′-biny)(CCl3CO2)2(H2O)]n have been synthesized and characterized by elemental analysis, IR spectra, thermal analysis and single-crystal X-ray diffraction for 1 and 2.

TL;DR: A series of N(4)-substituted thiosemicarbazones of isatin were synthesized and their copper(II) complexes were prepared from copper-II chloride X-ray crystal structures of two of them.

TL;DR: One-dimensional coordination polymers of [Cd(4,4′-bipy) 3 (H 2 O) 2 ](ClO 4 ) 2 · 2 H 2 O (1) were synthesized in a self-assembly process or by the ethanothermal reaction in a sealed tube as mentioned in this paper.

TL;DR: In this article, a series of copper-II complexes derived from 4-thienyl-methylidene amino antipyrine (TAAP) and 4-furfurylidene (FAAP) have been synthesized.

TL;DR: The title compound was prepared from 1-methyl-2(3H)-inidazolinethione and triphenyltin(IV) hydroxide, and its crystal structure was determined by X-ray diffraction.

TL;DR: From the reactions of SnCl4 with organotin(IV) chlorides (RSnCl3, R2SnCl2 and R3SnCl), a series of complexes have been synthesized and characterized, respectively, by microanalytical, IR, and 1H NMR spectroscopic methods as mentioned in this paper.

TL;DR: In this paper, new palladium(II) complexes of 2-acetylpyridine N(4)-propyl- and n(4)dipropyl-and 3-hexamethyleneiminylthiosemicarbazones with potentially interesting biological activity were described.

TL;DR: In this paper, structural features and physical properties of dmphen (2,9-dimethyl-1,10-phenanthroline) complexes with d10 metals ZnII, Ni0 and AgI were determined.

TL;DR: In this paper, a cyclic tetranuclear manganese(III) complexes with Schiff base ligands, N,N′-substituted-salicylidene-1,3-diaminobenzene (X = H, 5-Br), X-salmphenH2, MnIII4(X-Salmphen)6 have been prepared and characterized by spectroscopies, magnetic susceptibility, electrochemical measurements and X-ray crystallography.

TL;DR: In this article, a multisite Langmuir-Hinshelwood rate model is used to model the behavior of polycyclic aromatic N-containing molecules based on a combination of the HDN reactions of aniline and pyridine-like molecules.

TL;DR: In this paper, the authors provide an overview of the heterogeneous HDN process and outline various homogeneous models for hydrodenitrogenation catalysis including binding modes of HDN substrates, catalytic hydrogenation processes and recent CN bond cleavage reactions of nitrogen heterocycles.

TL;DR: In this paper, the crystal and molecular structure of the bis{S-methyl-β-N-(6-methylpyrid-2-yl)methylenedithiocarbazato}nickel(II) complex has been determined by X-ray diffraction studies.

TL;DR: In this article, a binuclear structure has been proposed for the OVadium(IV) complexes of aroyl hydrazone Schiff bases, viz. salicyloyl, nicotinoyl and benzoyl hydrazones, have been synthesized and characterized by elemental analysis, spectroscopy (IR and UV-vis) methods, magnetic susceptibility, EPR measurements, molar conductance and cyclic voltammetry studies.

TL;DR: In this paper, the relative rates of desulfurization can be correlated with CS bond strengths and the product distributions for molecules that form radical or cation intermediates and undergo various rearrangement reactions are used to elucidate reaction mechanisms.

TL;DR: The structure of the thiophene, benzothiophene and dibenzothiophenes insertion complexes have been determined in this article, and the mechanism of CS cleavage was found to proceed by way of initial sulfur coordination.

TL;DR: In this article, the crystal structures of I, II, as well as the neutral molecule HDTolF (III ) and the salt [H 2 DTolF][BF 4 ] ( IV ) are presented.

TL;DR: The reaction of 1-(4-fluorophenyl)-1,2-dicarbadodecaborane(12) with tetrabutylammonium fluoride hydrate in tetrahydrofuran or acetonitrile has been monitored by 19F and 11B NMR as discussed by the authors.

TL;DR: In this paper, the first example of an Iodo derivative with this coordination was presented, to the best of our knowledge, for chloro and bromo derivatives, which are isomorphous, and the pyrazine ring planes are perpendicular to the plane of the layer.

TL;DR: In this paper, the tridentate heterodonor (ONS)2− ligands have been used to obtain a basic VO(ONS) core with S-methyl 3-(2-hydroxyphenyl) methylenedithiocarbazate (H2L1) and its nitro- (H 2L2) and bromo derivatives.