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381.
I. A. Novakov V. V. Korolkov A. I. Pavlyuchko L. A. Gribov 《Journal of Structural Chemistry》2005,46(1):159-163
The structure of the dimer associates of aniline and n-propylamine with dimethylsulfoxide, isobutyronitrile, and N-methylpiperidone was investigated by ab initio calculations. Stable configurations of the complexes and their structural and energy characteristics have been determined. The effects of the nature of the solvent and the structure of the associate on the properties of the NH2 group are examined. 相似文献
382.
Flash vacuum pyrolysis of phenylazonaphthols and nitrosonaphthols at 700°C and 0.02 Torr yielded quinoline, isoquinoline, indene and naphthols (and aniline only from the phenylazo derivatives). Similar FVP of p-nitroso and p-phenylazophenol gave pyridine. Also, FVP of phenanthraquinonemonophenylhydrazone and monooxime gave phenathridine and fluorenone. The formation of the heterocyclic system was assumed to involve nitrene and azatropone intermediates. 相似文献
383.
On-line preconcentration on a short C18 column, prior to HPLC with UV and electrochemical detection, has been used for determination of some phenylurea herbicides and their possible degradation products, substituted anilines, in water samples. With electrochemical detection the detection limit at a signal-to-noise ratio of 3 was 5 ppt for 4-chloroaniline and 4-bromoaniline and 7 ppt for 3,4-dichloroaniline; with UV detection the detection limit was ca 300 ppt for all analytes. 相似文献
384.
R. R. Gataullin T. V. Kazhanova A. A. Fatykhov L. V. Spirikhin I. B. Abdrakhmanov 《Russian Chemical Bulletin》1990,49(1):174-176
ortho—para-Migration of the cyclopentenyl fragment in 2-(cyclopent-1′-enyl)aniline or 2-(cyclopent-1′-enyl)-6-methylaniline hydrochloride
at 200 °C gives 4-cyclopentylaniline or 4-cyclopentyl-2-methylaniline.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 171–173, January, 2000. 相似文献
385.
Dodonov V. A. Zaburdaeva E. A. Stepovik L. P. Cherkasov V. K. 《Russian Chemical Bulletin》2003,52(4):910-915
The tri-tert-butoxyaluminum—tert-butyl hydroperoxide system generates molecular oxygen in the electron-excited singlet state (1O2), which oxidizes diphenylamine, N-ethylaniline, aniline, and 2,6-diisopropylaniline to form nitroxyl radicals. The latters were identified by ESR at 240—293 K. Oxidation proceeds via the intermediate formation of nitrogen-containing N-peroxide compounds. 相似文献
386.
Sungsik Baek Jason J. Ree Moonhor Ree 《Journal of polymer science. Part A, Polymer chemistry》2002,40(8):983-994
Poly(o‐aminophenethyl alcohol) and its copolymers containing the aniline unit were synthesized in aqueous hydrochloric acid medium by chemical oxidative polymerization. The chemical composition of these novel polymers was determined spectroscopically, and their viscosities were measured. These polymers exhibit good solubility in organic solvents that is attributed mainly to the polar hydroxyethyl side groups. Their structures (chain conformation and morphological structure) and properties (conductivity, electrochemical characteristics, glass transition, and degradation behavior) were characterized and then interpreted on the basis of the chemical composition along with the electronic and steric hindrance effects associated with the hydroxyethyl side group. Overall, the side group has a significant effect on the polymerization and influences the structure, chain conformation, and properties of the resultant polymer. The poly(aniline‐co‐o‐aminophenethyl alcohol)s containing 20–40 mol % o‐aminophenethyl alcohol units are potential conducting materials for microelectronic and electromagnetic shielding applications because they are easier to process than polyaniline but retain its beneficial properties. These polymers can also be used as a functional conducting polymer intermediate owing to the reactivity of the side group. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 983–994, 2002 相似文献
387.
I. A. Novakov V. V. Korolkov A. I. Pavlyuchko B. S. Orlinson L. A. Gribov 《Journal of Structural Chemistry》2004,45(4):563-569
An ab initio (6-31G**) study of binary associates of aniline and n-propylamine with nitrobenzene and m-cresol has been carried out. The structures corresponding to the total energy minimum of the system have been found for the associates, and their geometrical and energy characteristics have been determined. Basic types of intermolecular interactions have been established, and their effects on the reactivity of the amino group have been investigated.Original Russian Text Copyright © 2004 by I. A. Novakov, V. V. Korolkov, A. I. Pavlyuchko, B. S. Orlinson, and L. A. GribovTranslated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 4, pp. 595–601, July–August, 2004.This revised version was published online in April 2005 with a corrected cover date. 相似文献
388.
Gataullin R. R. Nasyrov M. F. D"yachenko D. I. Fatykhov A. A. Shitikova O. V. Spirikhin L. V. Abdrakhmanov I. B. 《Russian Chemical Bulletin》2002,51(1):124-127
Treatment of the ozonization products from N-acetyl- or 2-methyl-N-trifluoroacetyl-6-(cyclopent-1-enyl)anilines with NaBH4 gives 6-methyl-2-tetrahydropyranylaniline. When treated with Me2S, the ozonization products yield the corresponding oxoaldehyde dimethyl acetals. The oxidation of N-acetyl-2-(cyclopent-1-enyl)- or -(cyclohex-1-enyl)anilines with H2O2 in HCOOH affords -(2-acetamidophenyl)-5-oxopentanoic or -6-oxohexanoic acid, respectively. The reaction of N-acetyl-2-(cyclopent-1-enyl)aniline with H2O2 in the presence of Na2WO4 and H3PO4 gives 3,1-benzooxazine in high yield. 相似文献
389.
Summary Fluorescamine (fluram) has been used as a fluorogenic compound for pre-column derivatization of aniline and some derivatives.
Anilines were derivatized with fluram in citrate buffer media (pH 5.5) to form pyrrolinones. The highly fluorescence pyrrolinones
were isolated and pre-concentrated by solid phase extraction. A reversed phase, Spherisorb RP-8 column and tetrahydrofuran:
water:formic acid (42:56:2) mobile phase was used for separation. Detection method was by a sensitive fluorimetric method
and quantitation was at 395 and 495 nm. The various parameters such as reaction conditions between anilines and fluram, solid
phase extraction and chromatographic separation were optimized. Calibrations were linear over the range considered with excellent
correlation coefficients (r>0.999). Relative standard deviations are less than 2.5 % and detection limits for aniline,p-toluidine, 4-chloroaniline and 4-bromoaniline were 6, 30, 6 and 8 ng L−1, respectively. This method has been used successfully for the determination of anilines in environmental waters. 相似文献
390.