6246-98-6Relevant articles and documents
Photosensitive oligomer formation and laser-induced polymerization of aniline on a gold electrode surface: A surface-enhanced Raman scattering study
Ishioka, Toshio,Uchida, Tatsuya,Teramae, Norio
, p. 765 - 766 (1998)
The process of laser-induced electropolymerization of aniline was studied by in situ surface-enhanced Raman scattering (SERS) spectroscopy and cyclic voltammetry (CV). Formation of p-coupled aniline oligomers was confirmed at an electrode potential below the oxidation potential of aniline, and the oligomers were found to be the source compound for photoinduced electropolymerization.
Structure and properties of polyaniline as modeled by single-crystal oligomers
Shacklette,Wolf,Gould,Baughman
, p. 3955 - 3961 (1988)
A single-crystal charge-transfer complex of a phenyl-end-capped tetramer of polyaniline has been synthesized and studied along with a similar dimer of polyaniline. Structural, optical, and electrochemical studies of these oligomers in various oxidation states provide detailed information which has been used to model the structure of polyaniline and its evolution during electronic doping. These studies of the polymer and its oligomers suggest that the emeraldine salt form of the polymer (50% doping per nitrogen) is a preferred low-energy structure. The preference for this structure leads to phase segregation in doped compositions having average doping levels less than 50%.
A comparative study of intermolecular interactions in the crystal structures of phenyl/phenyl end-capped oligoanilines
Gawlicka-Chruszcz, Anna,Stadnicka, Katarzyna
, p. o416-o420 (2002)
Three crystal structures have been analysed from the point of view of intermolecular interactions: N,N′-diphenyl-1,4-benzoquinone diimine, C18H14N2, (I), its reduced form N,N′-diphenyl-1,4-phenylenediamine, C18H
Electrochemical synthesis of N1,N4-diphenyl-2-(phenylsulfonyl)benzene-1,4-diamine derivatives: Introducing an example of ECDispCMich mechanism
Kaihani, Sajad,Salehzadeh, Hamid,Nematollah, Davood
, p. 166 - 174 (2015)
The electrochemical oxidation of N,N'-diphenyl-l,4-phenylenediamine (DPD) has been studied using cyclic voltammetry and controlled potential coulometry methods. The results revealed that DPD shows two one-electron oxidation-reduction peaks. In the first step DPD via a single-electron process is converted to the related radical cation (DPD.+) and second step is conversion of DPD.+ to N-(4-(phenylimino) cyclohexa-2,5-dienylidene) benzenamine (CHD) via a one-electron/two-protons process. Our results also show that DPD.+ participates in disproportionation reaction and is converted to DPD and CHD. The rate of this reaction is pH dependent and increases with increasing pH. Furthermore, the electrochemical oxidation of DPD has been studied in the presence of arylsulfinic acids as nucleophiles. The results showed that electrochemically generated CHD participates in Michael addition reaction with arylsulfinic acids via a novel ECDispCMich mechanism and is converted to the N1,N4-diphenyl-2-(phenylsulfonyl)benzene-1,4-diamine derivatives. In this work, a facile and green electrochemical method for the synthesis of some new N1,N4-diphenyl-2-(phenylsulfonyl)benzene-1,4-diamine derivatives in good yields using controlled-potential electrolysis at a carbon electrode is also reported.
Antioxidant action of the antihypertensive drug, carvedilol, against lipid peroxidation
Noguchi, Noriko,Nishino, Kimihiro,Niki, Etsuo
, p. 1069 - 1076 (2000)
The action of carvedilol, a vasodilating, β-adrenoceptor blocking agent, against lipid peroxidation has been the subject of many studies, but the results reported thus far are contradictory. In an attempt to define the antioxidant mechanism of carvedilol
Solvent effect on the equilibrium constant of the chain reversible reaction of N,N'-diphenyl-1,4-benzoquinonediimine with 2,5-dichlorohydroquinone
Gadomsky,Varlamov
body text, p. 2376 - 2383 (2009/02/05)
The temperature dependences of the equilibrium constant K of the reversible chain reaction of N,N'-diphenyl-1,4-benzoquinonediimine with 2,5-dichlorohydroquinone in benzene, chlorobenzene, anisole, benzonitrile, and CCl4 were studied. The enthalpies and entropies of the reaction in these solvents were determined, and a linear dependence between them in aromatic solvents was found. The equilibrium constant depends on the solvent nature: the replacement of CCl4 by benzene at T = 298 K increases K from 13.6 to 140. The solvation effects are caused by several types of intermolecular interactions of participants of equilibrium with the medium. The decrease in K in the benzene-anisole-benzonitrile series is related, to a great extent, to complex formation with hydrogen bonding between 2,5-dichlorohydroquinone and the solvents. In anisole a charge-transfer complex is formed between the solvent and reaction product (2,5-dichloroquinone). The constant and enthalpy of the complexation were estimated.
Determination of dissociation energies of N-H bond in the 4-anilinodiphenylaminyl radical and O-H bond in the 2,5-dichloro-4- hydroxyphenoxyl radical from the equilibrium constants of chain reactions in quinoneimine-hydroquinone systems
Antonov,Gadomsky,Varlamov
, p. 1723 - 1728 (2008/02/09)
The temperature dependences of the equilibrium constants of two chain reversible reactions in quinonediimine (quinonemonoimine)-2,5- dichlorohydroquinone systems in chlorobenzene were studied. The enthalpy of equilibrium of the reversible reaction of quinonediimine with 4-hydroxydiphenylamine was estimated from these data (ΔH = - 14.4±1.6 kJ mol-1) and a more accurate value of the N-H bond dissociation energy in the 4-anilinodiphenylaminyl radical was determined (DNH = 278.6±3.0 kJ mol-1). A chain mechanism was proposed for the reaction between quinonediimine and 2,5-dichlorohydroquinone, and the chain length was estimated (ν = 300 units) at room temperature. Processing of published data on the rate constant of the reaction of styrylperoxy radicals with 2,5-dichlorohydroquinone in the framework of the intersecting parabolas method gave the O-H bond dissociation energy in 2,5-dichlorohydroquinone: DOH = 362.4±0.9 kJ mol-1. Taking into account these data, the O-H bond dissociation energy in the 2,5-dichlorosemiquinone radical was found: DOH = 253.6±1.9 kJ mol-1.
Process for preparing N,N'-disubstituted P-quinonediimines, their use and organosilanes containing methacryloxy or acryloxy groups, processes for their stabilization and their preparation
-
, (2008/06/13)
The invention relates to a process for preparing N,N'-disubstituted p-quinonediimines of general formula I STR1 wherein a corresponding N,N'-disubstituted p-phenylenediamine is oxidized in alkaline/alcoholic solution, and also their use. The invention further provides organosilanes containing methacryloxy or acryloxy groups and having general formula II STR2 where R3 is a hydrogen atom or a methyl group and R4 and R5 are identical or different alkyl groups having from 1 to 4 carbon atoms and m is equal to 0 or 1 or 2, which organosilanes contain N,N'-disubstituted p-quinonediimines. Processes for preparing and stabilizing organosilanes of general formula II are described.
SYNTHESIS AND REACTIONS OF TRIPHENYLARSINIMINES
Froeyen, Paul
, p. 37 - 48 (2007/10/02)
Triphenylarsinimines formed in situ from isocyanates and triphenylarsine oxide have been found to react smoothly with carbonyl compounds like aldehydes, quinones and aromatic ketones giving the corresponding Schiff's bases in high yields.In the case of aldehydes, quinones or activated ketones, e.g., α-diketones, only a catalytic amount of triphenylarsine oxide is necessary for the reaction to proceed to completion.Quinones react with particular ease.Thus the previously unknown 9,10-phenanthrenequinone N-phenylimine 12 (R = Ph, Scheme IV) can be prepared in high yield from 9,10-phenanthrenequinone and phenyl isocyanate under catalytic influence of triphenylarsine oxide.Orthoquinones like 9,10-phenanthrenequinone react with vinylic isocyanates, forming monoimines 13 which rearrange to 1,4-oxazines 14 (Scheme V).Diisocyanates react under the catalytic action of triphenylarsine oxide with dialdehydes under mild conditions, forming some interesting new polymers 25, 26 in high yields.Reactions with aliphatic isocyanates give N-alkyl-N'-arylcarbodiimides, whereas reactions with isothiocyanates proceed through intermediates 20 and 21 to mixed carbodiimides 16, 24 and 25. Key words: Triphenylarsinimines; synthesis; reactions; Schiff's bases; unsymmetrical carbodiimides; polymers.
THE EFFECT OF 1,4-PHENYLENEDIAMINE ANDIDEGRADANTS ON THE PHOTO-OXIDATIONM OF SELECTED LIQUID HYDROCARBONS
Kotulak, Ludovit,Rotschova, Jitka,Pospisil, Jan
, p. 3384 - 3395 (2007/10/02)
The effect of six N,N'-disubstituted 1,4-phenylenediamines (I) and four derivatives of 1,4-benzoquinonediimine (II) on the photo-oxidation of tetralin, squalane and squalene at 35 deg C and radiation 300-400 nm was investigated by oxygen uptake measuremen
