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σ-Holes promote the concertedness in nucleophilic aromatic substitution reactions of nitroarenes
(Royal Society of Chemistry, 2019)
The mechanism of the SNAr reactions between 1-halo-2,4-dinitrobenzenes and amines was revisited by means of DFT calculations. Remarkably and contrary to the traditional text-book perspective, the dehalogenation of ...
Solvent effect on a model SNAr reaction in ionic liquid/water mixtures at different compositions
(Royal Society of Chemistry, 2018)
The reaction of phenyl 2,4,6-trinitrophenyl ether and piperidine was kinetically evaluated in BMIMBF4/water mixtures as the reaction media. This study shows the dramatic effect of the mixture composition on the reacting ...
Rede de conhecimento em estequiometria: produção de animações e simulações em laboratório virtual como facilitador do ensino-aprendizagem em química
(Universidade Tecnológica Federal do ParanáPato BrancoBrasilUTFPR, 2014)
An interactive guide with animations created from adobe flash professional program (swf) contains scripts that will allow chemistry students carrying out experiments in a virtual laboratory using the experimental simulation ...
Effect of stirring on photoinitiated polymerization
(1988)
The polymerization of methyl methacrylate photosensitized by benzion methyl ether over a wide range of initiator absorbances was investigated. Both the polymerization rate and the polymer molecular weight distribution are ...
Synthesis of branched polyethylene from ethylene by tandem action of iron and zirconium single site catalysts
(2001)
The synthesis of low-density polyethylene from ethylene as the only monomer feed has been investigated as an alternative route to branched polyethylene and to obtain new materials with different properties, avoiding the ...
Silver(I) and copper(I) complexes with a Schiff base derived from 2-aminofluorene with promising antibacterial activity
(Elsevier S.A., 2019)
By reaction of 2-aminofluorene with 2-pyridinecarboxaldehyde a new Schiff base (L) is obtained. The reaction of this ligand with Ag(I) and Cu(I) salts in different stoichiometry leads to the complexes [Ag(CF3SO3)(L)PPh3] ...
NMR study of branched polyethylenes obtained with combined Fe and Zr catalysts
(2002)
The products obtained with the system {[(ArN=C(Me))2C5H3N]FeCl2}/MAO (Ar = 2-C6H4(Et)) (1) and the ones obtained by the use of 1 in conjunction with Me2SiInd2ZrCl2/MAO (2) or EtInd2ZrCl2/MAO (3) were completely characterized ...
Redox and coordinative properties of N,N′-dithiobisamines: Oxidative desulphurization by copper(II) ions and Cr(CO)5[S2(NR2)2] complexes
(1991)
N,N′-dithiobisamines, R2N-S-S-NR2, NR2N(CH3)2, N(CH2CH3)2, {A figure is presented}, {A figure is presented} or N(CH2-C6H5)2, are oxidized to SO2 by copper(II) salts with formation of copper(I) complexes, while from the ...
Complexes with heterocyclic nitrogen ligands - III. Cationic rhodium(I) derivatives and applications in catalysis
(Elsevier Ltd, 1996)
The preparation and spectroscopic properties of mononuclear cationic complexes of rhodium(I) coordinated to the diolefin 2,5-norbornadiene (NBD) and to the heterocyclic nitrogen ligands 6,7-dihydrodipyrido-[2,3-b:3′,2′-j ...
Binding of electrolytes to poly(ethylene oxide) in methanol
(1986)
The binding of potassium and sodium salts (thiocyanate and iodide as anions) to polyethylene
oxide) in methanol solutions has been studied. The study was performed by the use of fluorescence techniques
and ultrafiltration ...