scispace - formally typeset
Search or ask a question

Showing papers on "Nitrobenzene published in 1980"


Journal ArticleDOI
TL;DR: It is suggested that the reduction of nitrobenzene to an intermediate, possibly nitrosobenzenes or phenylhydroxylamine, limits the rate of aniline formation, and such an initial step of nitromine reduction can be catalyzed by NADPH-cytochrome c reductase alone.
Abstract: 1. The subcellular distribution of nitrobenzene reduction activity in rat liver cells indicated the existence of two different enzyme systems, one localized in microsomes and the other localized in cytosol. The activity in the cytosol was mainly attributable to xanthine oxidase, judging from its substrate specificity and the inhibition by allopurinol. 2. The participation of the microsomal electron transport system in nitrobenzene reduction was examined by using antibodies against four components of the system, NADPH-cytochrome c reductase (fpT), NADH-cytochrome b5 reductase (fpD), cytochrome b5, and cytochrome P-450. Both NADH- and NADPH-dependent nitrobenzene reduction activities were strongly inhibited by anti-fpT IG and also by anti-P450 IG, but not inhibited by anti-fpD IG or anti-b5 IG. The reduction of nitrosobenzene and phenylhydroxylamine, which are supposed to be the intermediates of nitrobenzene reduction, was also examined, and it was found that NADH- and NADPH-dependent reduction of both compounds were strongly inhibited by anti-fpT IG and anti-P450 IG, but not by anti-fpD IG or anti-b5 IG. 3. Reconstruction experiments using purified NADPH-cytochrome P-450 reductase and cytochrome P-450 were also carried out and it was confirmed that the reduction of nitrobenzene, nitrosobenzene, and phenylhydroxylamine to aniline could be effected by these two components. 4. Nitrobenzene reduction by microsomes exhibited a short initial time lag and was activated by the addition of purified NADPH-cytochrome c reductase, whereas nitrosobenzene and phenylhydroxylamine reductions did not show any initial time lag and were not activated by the reductase. These observations suggest that the reduction of nitrobenzene to an intermediate, possibly nitrosobenzene or phenylhydroxylamine, limits the rate of aniline formation, and such an initial step of nitrobenzene reduction can be catalyzed by NADPH-cytochrome c reductase alone. Cytochrome P-450 is essential at least in the final step of nitrobenzene reduction to aniline. This conclusion was further confirmed by determination of these intermediates in nitrobenzene reduction.

74 citations



Journal ArticleDOI
TL;DR: Montmorillonite, kaolinite, illite, and chlorite were found to adsorb bitumen and its pentane- soluble and pentaneinsoluble fractions.
Abstract: Montmorillonite, kaolinite, illite, and chlorite were found to adsorb bitumen and its pentane- soluble and pentane-insoluble fractions. The formation of clay-bitumen complexes is influenced by the nature of the exchangeable cation on the clay and by the solvent carrier which stabilizes the bituminous compounds. Ca-clays adsorb organic compounds more strongly than sodium forms except in the presence of nitrobenzene. Solvents of high dielectric constant, such as nitrobenzene, promote ionization so that the ion-exchange mechanism of adsorption is favored, whereas solvents of lower dielectric constant, such as chloroform, tend to solvate rather than to dissociate bitumens. The behavior of the montmorillonite-bi- tumen complex in variable relative humidity indicates that organic molecules adsorb primarily on external surfaces and cause the clay to become less hydrophilic than prior to treatment. Clay-organic complexes are sufficiently stable to resist powerful organic solvents. The clay-organic complex separated from the Athabasca oil sand behaves similarly during chemical treatment to complexes formed between bitumen and the four reference clay minerals.

67 citations


Journal ArticleDOI
TL;DR: In this article, the Karl-Fischer method was used to determine the quantity of water transferred to the nitrobenzene phase by means of the NMR and near-infrared spectra, showing that coextraction of water is caused by the hydration of the cations.
Abstract: Alkali and alkaline earth metal salts of 2,2′,4,4′,6,6′-hexanitrodiphenylamine (HND) were extracted into nitrobenzene in the absence or presence of several crown ethers or cryptands which differ from one another in hole size. The quantity of water transferred to the nitrobenzene phase was determined by means of the Karl-Fischer method. The NMR and near-infrared spectra show that the coextraction of water is caused by the hydration of the cations. The number of water molecules attached to the cations increases upon going from Cs+ (0.6) to Li+ (5.6) and from Ba2+ (10.5) to Ca2+ (13.0). The complexation between these cations and the crown ethers causes a clear decrease in the hydration number; e.g., in the 1:1 metal–crown ether complexes, more than half of the water molecules are removed, and in the 1:1 metal–cryptand complexes, less than one water molecule remains unremoved. The complexes of a 1:2 stoichiometry are also found; some are stable and carry virtually no water molecules. The number and type of do...

53 citations


Journal ArticleDOI
TL;DR: In this paper, the transfer of the picrate ion across the interface between two immiscible electrolyte solutions, 0.05 M LiCl in water and 0.5 M tetrabutylammonium tetraphenylborate in nitrobenzene, was investigated by electrolysis with the electrolyte dropping electrode and by cyclic voltammetry.

50 citations


Journal ArticleDOI
TL;DR: In this article, it was shown that the yield of nitrobenzene and the maximum current density for the reaction is dependent upon the solvent, the cathode metal, the electrode potential, the concentration of acid and the rate of stirring of the catholyte.
Abstract: The electrochemical reduction of nitrobenzene has been studied in aqueous organic solvents containing sulphuric acid. It is shown that the yield ofp-aminophenol and the maximum current density for the reaction is dependent upon the solvent, the cathode metal, the electrode potential, the concentration of acid and the rate of stirring of the catholyte. The changes of products would not be obvious from theI-E curves but it is possible to find conditions where the yield ofp-aminophenol is > 75% at a current density of 150 mA cm−2.

47 citations


Journal ArticleDOI
TL;DR: For compounds C6H5X (XCl, Br, I) under chemical ionization conditions, methylamine causes ipso substitution of X by [NH2CH3]- and by NH2]-˙ as mentioned in this paper.
Abstract: For compounds C6H5X (XCl, Br, I) under chemical ionization conditions, methylamine causes ipso substitution of X by [NH2CH3]+ and by [NH2]+˙. C6H5F is less reactive; it gives some [C6H5NH2]+˙. Nitrobenzene gives an adduct ion [M+CH3NH3]+, a reduction product ion [C6H5NO2]+˙, and an ion at m/z93, probably a substitution product [C6H5NH2]+˙, but no [C6H5NH2CH3]+. It is also shown that the ion m/z94, formed from nitrobenzene with ammonia as reagent gas, is a substitution product rather than a reduction product ion. Carbonyl compounds C6H5. CO. X give adduct ions and some substitution, mainly [C6H5NH2]+˙.

31 citations


Journal ArticleDOI
TL;DR: In this article, the substitutional chemisorption of benzene, pyridine, aniline, toluene, nitrobenzene and ethylenediamine on nickel and palladium has been studied at 295 K by X-ray photoelectron spectroscopy.

26 citations


Journal ArticleDOI
TL;DR: In this paper, it was shown by ion cyclotron resonance measurements that ion/molecule reactions, leading to substitution or reduction product ions from chloro- and nitrobenzene with the title amines, are those between the molecular ions [RNH2]+ or [C6H5X]+˙ and their respective counterparts C6H 5X or RNH2.
Abstract: It is shown by ion cyclotron resonance measurements that ion/molecule reactions, leading to substitution or reduction product ions from chloro- and nitrobenzene with the title amines, are those between the molecular ions [RNH2]+ or [C6H5X]+˙ and their respective counterparts C6H5X or RNH2. The protonated reagent gas ions [RNH3]+ are not involved in these reactions. In the case of nitrobenzene, adduct ions [C6H5NO2·RNH3]+ do not decompose within the time scale of the measurements. The results obtained are compared with those found under chemical ionization conditions.

23 citations


Journal ArticleDOI
TL;DR: In this paper, the authors describe the catalytic N-alkylation and N-heterocyclization of nitrobenzene at 180°C under pressures of carbon monoxide (70 atm) in the presence of aldehyde and transition metal complexes.
Abstract: The catalytic N-alkylation and N-heterocyclization of nitrobenzene occurs at 180°C under pressures of carbon monoxide(70 atm) in the presence of aldehyde and transition metal complexes to give 2,3-dialkyl quinoline and N,N-dialkylaniline in good yields. The product selectivity highly depends on the catalysts.

18 citations


Journal ArticleDOI
TL;DR: In this article, the liquid phase reduction of different substituted nitrobenzene derivatives with the formic acid-triethylamine system has been carried out by the use of a supported palladium (0,6%) on AlPO4/SIO2 (20:80 weigth) catalyst.
Abstract: The liquid phase reduction of different substituted nitrobenzene derivatives with the formic acid-triethylamine system has been carried out by the use of a supported palladium (0,6%) on AlPO4/SIO2 (20:80 weigth) catalyst. The reduction rate of nitrocompounds containing electron-acceptor substituents is much higher than that of electron donor-containing substrates.

Journal ArticleDOI
TL;DR: In this article, the back extraction of methyltrioctylammonium chloride (MTOACl) from ten kinds of organic solvents was investigated as a function of the ammonium concentration, and the selectivity coefficients (KX/Cl) of MTOA for the exchange of Br−, I−, ClO4−, vs.
Abstract: The back extraction of methyltrioctylammonium chloride (MTOACl) from ten kinds of organic solvents was investigated as a function of the MTOACl concentration. The chemical species of the ammonium salt in the organic phase were found to be in the form of dissociated ions, of ion pairs, or of dimeric ion pairs, according to the dielectric constant of the solvent. MTOACl was better extracted into more polar and acidic solvents, such as nitrobenzene, 3-methyl-1-butanol, and chloroform. The selectivity coefficients (KX/Cl) of MTOA for the exchange of Br−, I−, ClO4−, vs. Cl− were obtained from the study of the distribution of several organic color reagents; they were found to increase with the anion size, irrespective of the organic solvent used. For all but acidic solvents, the values of KX/Cl were similar to each other. Such acidic solvents as 3-methyl-1-butanol and chloroform, however, reduced the selectivity of the extraction for anions.


Journal ArticleDOI
TL;DR: In this article, the excess volumes of an n-alkanol + nitrobenzene and + chlorobenzene for n-propanol, nbutanol, n-pentanol, and n-hexanol have been measured as a function of composition at 303.15 K by a dilatometric method.

Journal ArticleDOI
TL;DR: In this paper, the plat inum and palladium complexes containing alizarin were used as catalysts for conversion of n i t robenzene into aniline 141, and the results showed that these catalysts were very effective in the hydrogenat ion of nitroaromatics.
Abstract: The hydrogenat ion of nitroaromatics occurs with great o efficiency in the presence of only a small number of complex catalysts ~1-4) Earlier it was proposed (sl that the low activity of the 1 majori ty of metallocomplex catalysts in the latter reaction arose from the noncomplementary nature of the process: i.e. the intermediates metal-hydrides are two-electron donors, whereas nitroaromatics are one-electron acceptors. In previous reports ~ '4 '5 ) , metallocomplexes containing quinones or dyes as ligands were shown to be very effective catalysts in the hydrogenat ion of nitroaromatics, apparently 0.5 owing to their ability to transform the two-electron into a oneelectron process (6). In this work we have investigated the plat inum(II) and palladium(II) complexes containing alizarin as catalysts for conversion of n i t robenzene into aniline 141.

Patent
14 Apr 1980
TL;DR: In this paper, an aromatic carbamic acid ester is synthesized by reacting an aromatic nitro compound with a hydroxyl-containing organic compound (e.g., methanol, phenol, etc.) in the presence of a catalyst.
Abstract: PURPOSE:To prepare the titled compound in high yield, by reacting an aromatic nitro compound with carbon monoxide and excess organic compound containing hydroxyl group in the presence of a catalyst using a specific organic solvent. CONSTITUTION:An aromatic carbamic acid ester is synthesized by reacting an aromatic nitro compound (e.g. nitrobenzene) with a hydroxyl-containing organic compound (e.g. methanol, phenol, etc.) and carbon monoxide in the presence of a catalyst (e.g. Pd, Pt, etc.). The amount of the hydroxyl-containing organic compound is adjusted to 1.1-15mol per 1 equivalent of the nitro group of the aromatic nitro compound, and the reaction is carried out in the presence of 0.1- 15pts.vol., based on 1pt.vol. of the hydroxyl-containing organic compound, of an organic solvent (e.g. hydrocarbons, halogenated hydrocarbons, nitriles, ethers, etc.). High reaction activity can be achieved by the use of said solvent, and accordingly, the corrosive action of the reaction system can be mitigated by reducing the concentration of the catalyst.

Journal ArticleDOI
TL;DR: The catalytic hydrogen transfer reactions between hydroaromatics and nitrobenzene over polynaphthoquinone catalyst were found to proceed with 98-100% selectivities in the temperature range 300-330 °C in conjunction with the redox cycle of surface quinone and hydroquinone groups as discussed by the authors.

Journal ArticleDOI
TL;DR: In this article, the reagent prepared from 2 PhMgBr and CuI reacts with allyl and benzyl bromides to give allylbenzene and diphenylmethane, respectively, in 52 and 62% yields.

Patent
13 Mar 1980
TL;DR: In this paper, an improved process for the preparation of nitrosobenzene by catalytically reducing it with a reducing agent selected from the group consisting of aliphatic compounds containing from about 1 to about 20 carbon atoms.
Abstract: An improved process for the preparation of nitrosobenzene by catalytically reducing nitrobenzene with the use of a reducing agent selected from the group consisting of aliphatic compounds containing from about 1 to about 20 carbon atoms, cycloaliphatic compounds containing from about 4 to about 12 carbon atoms, benzene, naphthalene, and ethylenically unsaturated compounds containing from about 2 to about 10 carbon atoms is disclosed. The improvement comprises performing the reduction in the presence of from about 0.05 to about 4.0 moles of water per mole of nitrobenzene.



Journal ArticleDOI
TL;DR: A new monomer for the preparation for polyimidines has been synthesized from 3,3-diphenylphthalide as mentioned in this paper, which can be mononitrated on one of the pendant phenyl groups by the use of acetyl nitrate or nitronium tetrafluoroborate.
Abstract: A new monomer for the preparation for polyimidines has been synthesized from 3,3-diphenylphthalide. The starting material can be mononitrated on one of the pendant phenyl groups by the use of acetyl nitrate or nitronium tetrafluoroborate. The resulting nitrophthalide is then reduced to the amine with hydrogen over PtO2 or with ammonium sulfide with overall yields of 85–90%. 3-(p-Aminophenyl)-3-phenylphthalide then can undergo self-condensation to provide a new polyimidine with a rigid backbone structure which may be a candidate for liquid crystal formation. The condensation can take place at temperatures of 180–350°C, either in polyphosphoric acid or nitrobenzene as solvents, or without solvent in a sealed tube. The yield from the polymerization is as high as 89% and inherent viscosities range up to 0,19 dl/g. Thermal stabilities in air and nitrogen are as high as 520 and 565°C, respectively; however a significant difference occurs in thermal stability for different methods of synthesis. All polymers were soluble in chloroform, dimethylformamide and other organic solvents.


Journal ArticleDOI
TL;DR: By irradiation with a focused laser beam, p-nitroanisole and N-[2-(p-nitrophenoxy)ethyl] aniline (2) in acetonitrile were found to yield nitroso compounds different from the case of the defocused laser beam irradiation.
Abstract: By irradiation with a focused laser beam, p-nitroanisole and N-[2-(p-nitrophenoxy)ethyl] aniline (2) in acetonitrile were found to show new reactions yielding nitroso compounds different from the case of the defocused laser beam irradiation. The laser intensity dependence of the product yield shows that the new reaction of 2 proceeds via a biphotonic process. The quenching effects of oxygen and cis-1,3-pentadiene upon the reaction rate indicate that the intermediate state is an excited singlet state.

Journal ArticleDOI
01 Apr 1980
TL;DR: In this paper, the change of interfacial tension induced by the flow of an electric current through a nitrobenzene-water interface was studied experimentally and theoretically for both ac and dc.
Abstract: The change of interfacial tension induced by the flow of an electric current through a nitrobenzene-water interface was studied experimentally and theoretically for both ac and dc. The nitrobenzene and water phases contain some hexadecyltrimethylammonium bromide, and a supporting electrolyte (or KBr in the water phase or hexadecyltrimethylammonium picrate in nitrobenzene). The overpotential measured while an electric current flowed through the interface was zero. Concentration changes near the interface were observed, and compared with theory. The interfacial transport number which arises from these measurements as an adjustable parameter is compared with transference numbers in bulk.

Patent
19 Dec 1980
TL;DR: In this article, an aromatic nitro compound and a lower aliphatic alcohol or a phenol are made to react with CO in liquid phase in the presence of a catalyst containing a platinum-group metal (e.g., Pd, Rh, etc.) at 100W250°C to obtain an aromatic urethane.
Abstract: PURPOSE: To prepare the titled compound economically, by reacting an aromatic nitro compound and a lower a aliphatic alcohol or a phenol in liquid phase in the presence of a catalyst containing platinum-group metal with CO preparaed by specific method, and circulating and reusing the exhaust gas of the reaction. CONSTITUTION: An aromatic nitro compound (e.g. nitrobenzene) and a lower aliphatic alcohol (e.g. methanol) or a phenol are made to react with CO in liquid phase in the presence of a catalyst containing a platinum-group metal (e.g. Pd, Rh, etc.) at 100W250°C to obtain an aromatic urethane. The amount of the alcohol or phenol is 2W400mol, pref. 5W50mol per 1mol of the nitro group of the aromatic nitro compound. The CO gas is prepared by passing a mixed gas containing CO 2 and O 2 through the layer of coke heated at ≥900°C. The exhaust gas obtained after the completion of the urethane-forming reaction is recycled to the above coke layer. COPYRIGHT: (C)1982,JPO&Japio

Journal ArticleDOI
TL;DR: Graft copolymerization of poly(vinyl chloride) (PVC) partially dehydrochlorinated by heating in nitrobenzene was investigated using styrene as monomer and anhydrous AlCl3 as cationic initiator in the temperature range of 0-35°C as discussed by the authors.
Abstract: Graft copolymerization of poly(vinyl chloride) (PVC) partially dehydrochlorinated by heating in nitrobenzene was investigated using styrene as monomer and anhydrous AlCl3 as cationic initiator in the temperature range of 0–35°C. Effect of monomer, catalyst, and PVC concentration on % graft-on was also evaluated. Introduction of labile sites in PVC by partial dehydrochlorination in nitrobenzene resulted in an increase in % graft-on. Intrinsic viscosity of PVC–g–polystyrene in THF initially increased with an increase in % graft-on. At higher % graft-on a decrease in [η] was observed.

Journal ArticleDOI
TL;DR: In this paper, the total thermal changes arising from mutual saturation of benzene, toluene, chlorobenzene, nitrobenzene and 1,2-dichloroethane with water were determined at 29815 K from a combination of these values with known solubility data.
Abstract: Using a direct microcalorimetric technique, the total thermal changes arising from the mutual saturation of benzene, toluene, chlorobenzene, nitrobenzene and 1,2-dichloroethane with water were determined at 29815 K From a combination of these values with known solubility data, the enthalpies of solution of water in the organic solvents and of the organic compounds in water were derived by least-squares analysis

Journal ArticleDOI
TL;DR: In this article, the association constants of the metal chelate ions with nitrobenzene in water were determined using the solubility of NitrobenZene in their aqueous solutions.

Journal ArticleDOI
TL;DR: An analytical method based on the direct coupling of the dye sodium salt of 1,2-naphthoquinone-4-sulphonic acid with the chemically converted nitrobenzene (NB) and p-nitrochlorobenzene (NCB) to aniline andp-chloroaniline in aqueous medium and carbon tetrachloride is found to be a selective solvent for extraction.
Abstract: An analytical method based on the direct coupling of the dye sodium salt of 1,2-naphthoquinone-4-sulphonic acid with the chemically converted nitrobenzene (NB) and p-nitrochlorobenzene (NCB) to aniline and p-chloroaniline in aqueous medium (pH 7.0-9.0) is presented. The coupled dye is extracted in carbon tetrachloride and spectrophotometrically determined at 450 nm wavelength. Carbon tetrachloride is found to be a selective solvent for extraction of aniline and its analogous coupled derivative of the dye, thus the interference of the other urinary nitro and amine compounds normally present is removed. Ethanol and isopropyl alcohol are efficient sampling media for trapping airborne NB and NCB vapors. The sensitivity and precision of the method are 10 micrograms and 3.5%, respectively, for NB and NCB in air samples. The sensitivity and precision of this method for urinary NB and NCB estimation is 0.8 mg/L and 0.6 mg/L; and 6.1% and 4.0%, respectively.