467-63-0Relevant academic research and scientific papers
"Catalytic" Effects of Electrically Charged Polymer Latices on Interionic Reactions
Ishiwatari, Tsutomu,Maruno, Tohru,Okubo, Masayoshi,Okubo, Tsuneo,Ise, Norio
, p. 47 - 50 (1981)
Anionic latices, copolymers of styrene (St) and acrylic acid (AA), were sythesized, and their "catalytic" influences on interionic reactions between oppositely charged species, i.e., reaction between Co(NH3)5Br2+ and OH- and between crystal violet and OH-, were studied.The latices retarded the reactions, as was the case with anionic macroions.For the former reaction, the latices of higher AA content demonstrated greater retarding effects, indicating that the electrostatic interaction is important.For the latter reaction, on the other hand, there was no difference in the retarding effects of the latices, which implies that the hydrophobic interaction of the latices with the reactant ions plays a more important role than the electrostatic interaction.The activation parameters including the volume of activation were discussed in terms of these interactions.The "catalytic" influences of the latices and linear polymers (sodium polyacrylate and poly(styrenesulfonate)) were also compared.
Influence of colloid suspensions of humic acids upon the alkaline fading of carbocations
Arias-Estevez,Astray,Cid,Fernandez-Gandara,Garcia-Rio,Mejuto
, p. 555 - 560 (2008)
The influence of humic substances (HSs) upon the alkaline hydrolysis of crystal violet (CV) and malachite green (MG) has been studied. Important inhibition of hydrolysis reaction has been reported. This inhibition has been explained in terms of association of reactants to the humic substances. Kinetic results have been modelized using the micellar pseudophase model. Copyright
Study of association thermodynamics between crystal violet and sodium bis(2-ethylhexyl)-sulfosuccinate and kinetics of basic fading of crystal violet in microemulsions
Chen, Zhi Yun,Zhao, Ji Hua,He, Wei,An, Xue Qin,Shen, Wei Guo
, p. 294 - 300 (2008)
The thermodynamics of the association between 4,4′,4″- tris(dimethylamino)triphenylmethyl chloride (crystal violet or CV) and sodium bis(2-ethylhexyl)-sulfosuccinate (aerosol OT or AOT) in water/AOT/n-decane microemulsion and the kinetics of the basic hydrolysis of CV in a water-in-oil microemulsion were investigated by UV-vis spectroscopic measurements. An association model of CV and AOT was used to analyze the experimental data to obtain the association constants at various temperatures. By taking the association into account, the "actual" rate constants and the activation energies of the basic hydrolysis of CV in the media of water/AOT/oil were obtained. The difference in thermodynamics and kinetics between the two media of water/AOT/n-decane and water/AOT/isooctane is discussed.
Reactions of Carbocations with a Functionalized Hydrophobic Ammonium Ion
Bunton, Clifford A.,Dorwin, Ellen L.
, p. 4093 - 4096 (1986)
At high pH (2-hydroxyethyl)tri-n-octylammonium bromide and mesylate 2 react readily with Malachite Green or Crystal Violet to give the corresponding ethers.Reaction is promoted by association of the carbocations with clusters of 2 and involves the nucleophilic zwitterion of 2.Reactions are considerably faster than those with OH- or the cholinate zwitterion, but second-order rate constants in the clusters are lower than in micelles of (2-hydroxyethyl)dimethylhexadecylammonium bromide (1) by a factor of ca. 4.
Kinetics of fading of some triphenylmethane dyes: Effects of electric charge, substituent, and aqueous binary mixtures of dimethyl sulfoxide and 2-propanol
Samiey,Dalvand
, p. 60 - 70 (2014)
The rate constants of alkaline fading of a number of triphenylmethane (TPM) dyes including methyl green (ME2+), brilliant green (BG +), fuchsin acid (FA2-), and bromophenol blue (BPB 2-) were obtained in aqueous binary mixtures of 2-propanol (protic solvent) and dimethyl sulfoxide (DMSO) (aprotic solvent) at different temperatures. It was observed that the reaction rate constants of BG+ and ME2+ increased and those of FA2- and BPB2- decreased with an increase in weight percentages of aqueous 2-propanol and DMSO binary mixtures. 2-Propanol and DMSO interact with the used TPM molecules through hydrogen bonding and ion-dipole interaction, respectively, in addition to their hydrophobic interaction with TPM dyes. The fundamental rate constants of a fading reaction in these solutions were obtained by the SESMORTAC model. Also, the effect of electric charge and substituent groups of a number of TPM dyes on their alkaline fading rate was studied.
The optical properties of triphenylmethane dye molecules and chromogens
Mikheev,Guseva,Ershov
, p. 1580 - 1588 (2008)
Industrial dye monomers, including malachite green, crystal violet, brilliant green, and methyl violet, were isolated by extraction with the use of heptane. UV light absorption bands characteristic of pure molecules were determined. The molecules of the dyes studied, which were ion pairs (formed by dye cations and oxalate or chlorine anions), did not absorb light in the visible range; that is, they were not chromogens. The conclusion was drawn that chromogen particles responsible for chromaticity were supramolecular dimers of nonchromogenic triphenylmethane series molecules. This conclusion was substantiated by trends in spectral transformations with the participation of immonium hydroxides obtained from dyes and side products of the synthesis of industrial dyes with quinoid molecular structures.
Micellar rate effects in the alkaline fading of crystal violet in the presence of various surfactants
Roshchyna, Kateryna V.,Eltsov, Sergey V.,Laguta, Anna N.,McHedlov-Petrossyan, Nikolay O.
, p. 77 - 82 (2015)
The influence of surfactants of various types (nonionic, cationic, anionic, and zwitterionic) on the rate of reaction of the crystal violet, cationic triphenylmethane dye, with the hydroxide ion in unbuffered aqueous solutions was studied using the spectrophotometric method. It was found that the values of the rate constants increase in the presence of the cationic, nonionic and zwitterionic surfactants, and decrease on the addition of the anionic surfactant at concentrations both below and above the CMC. The variation of the rate constants along with the change in the concentration of the surfactants may be explained on the basis of conception about distribution of the reagents between aqueous and micellar phases and the changing of their properties depending on local microenvironment. The character of the salt effects upon the rate constants was explained. It was revealed, that the Piszkiewicz's model of micellar catalysis is inapplicable even semi-quantitatively to the most of the examined systems.
Effect of Pressure on the Rate of Alkaline Fading of Triphenylmethane Dyes in Cationic Micelles
Taniguchi, Yoshihiro,Iguchi, Akira
, p. 6782 - 6786 (1983)
The rates of alkaline fading of triphenylmethane dyes in cationic micelles have been measured at pressures up to about 2 kbar and at 25 deg C in 0.1 M Tris buffer solution.These rates follow the kinetics of the Michaelis-Menten type.The volume changes for the incorporation of dyes in the micellar phase are 14-15 cm3/mol for ethyl violet and brilliant green and 3-4 cm3/mol for crystal violet and malachite green.It was confirmed that these differences are due to the hydrophobicity of dyes.The activation volumes for the fading reaction in micellar phases are positive except in the case of the crystal violet-cetyltrimethylammonium bromide micellar system.However, the activation volumes in nonmicellar aqueous solutions are negative.The differences of the activation volumes between micellar and nonmicellar systems are discussed from the point of view of the general base catalysis, which contains both the water and hydroxide ion pathways.It was clear that micelles change the water control into hydroxide ion control.
General acid catalysis in benzoic acid-Crystal Violet carbinol base reactions in toluene
Gupta, Susanta K. Sen,Mishra, Sangeeta,Rani, V. Radha,Arvind, Udai
, p. 570 - 576 (2012)
Kinetics of benzoic acid-dye carbinol base reactions in an apolar aprotic solvent exhibit a complex dependence on the concentration of the acid, indicating the occurrence of general acid catalysis, the acid playing the dual role of the substrate and the catalyst. The complex kinetic behavior observed for 23 ortho- and meta-substituted benzoic acids has been traced to overlapping participations of the monomer acid, hyperacidic open chain homoconjugated complex (dimeric and trimeric) acids, and nonreactive cyclic dimer and trimer acids. It has been found that although the degree of proton transfer in the transition state is 50-60% when the acid acts exclusively in the monomeric form, it gets enhanced to as high as more than 90% when the role of homoconjugated complex acids is taken into consideration.
Kinetics of proton transfer between ortho substituted benzoic acids and the carbinol base of crystal violet in toluene. Ortho effect on the reactivity of benzoic acids in apolar aprotic solvents
Sen Gupta, Susanta K.,Mishra, Sangeeta
experimental part, p. 4616 - 4623 (2011/06/26)
Apolar aprotic solvents are particularly advantageous for investigating the intrinsic ortho effect free from complications of specific solvent effects. A kinetic study for toluene-phase proton transfers between ortho F, Cl, Br, I, OMe, OEt, OPh, OAc, Me, NO2, COMe, COPh, OH, NH2, and H benzoic acids and crystal violet carbinol base has shown the forward rate constant (log k+1) is the most appropriate reactivity parameter in toluene. log k+1 (toluene) as compared to other reported reactivity parameters in benzene, toluene, or chlorobenzene has been found more sensitive to the ortho substituent effect. The regression results of the correlation of log k+1 (toluene) of the acids (except OH and NH2 substituted ones) according to seven ortho effect models are all very significant, and the best result is given by Fujita-Nishiokas model. The overall analysis reveals that a substituents ortho effect pattern is a 58:24:18 ratio of its ordinary electrical, proximity electrical, and steric effects and that the proximity electrical effect is the major component to account for the peculiarity of the substituents ortho effect. The results further favor the transmission of this effect mainly through the molecular cavity. The effect may, however, be outweighed by the steric component for bulky enough substituents, e.g., Me. The enhanced strength exhibited by salicylic acid in toluene has been quantitatively described using Pytela-Lisas δHB i parameter. The abnormally high log k+1 observed for anthranilic acid in toluene has been ascribed to a very extensive homoconjugation in its acid-acid anion complex induced by the acids three hydrogen bond donors.
