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1.
The geometries of N,N′-diphenylbenzene-1,4-diamine (DPPD), N-phenyl-N′-(1-phenylethyl)benzene-1,4-diamine (SPPD), N-(4-methylpentan-2-yl)-N′-phenylbenzene-1,4-diamine (6PPD), N-propan-2-yl-N′-phenylbenzene-1,4-diamine (IPPD), N-(2-methoxybenzyl)-N′-phenylbenzene-1,4-diamine (MBPPD), and N-phenyl-N′-(2-phenylpropan-2-yl)benzene-1,4-diamine (CPPD) as well as of their dehydrogenation products were optimized by the semiempirical
AM1 method. The results support the idea of stable NB=CX structures formation during the consecutive dehydrogenation of SPPD, 6PPD, IPPD, and MBPPD antioxidants. The biradicals formed
during the second step of dehydrogenation of substituted phenylenediamines might be important for their antioxidant effectiveness.
Dedicated to Professor Vladimír Kvasnička, DrSc., in honour of his 65th birthday 相似文献
2.
Maria D. M. C. Ribeiro da Silva Joana I. T. A. Cabral Chelsea Givens Stephanie Keown W. E. Acree Jr. 《Journal of Thermal Analysis and Calorimetry》2008,92(1):73-78
The standard (p
0=0.1 MPa) molar enthalpies of formation, in the gaseous phase, at T-298.15 K, for 2,5-dimethylpyrazine (2,5-DMePz) and for the two dimethylpyrazine-N,N′-dioxide derivatives, 2,3-dimethylpyrazine-1,4-dioxide (2,3-DMePzDO) and 2,5-dimethylpyrazine-1,4-dioxide (2,5-DMePzDO), were
derived from the measurements of standard massic energies of combustion, using a static bomb calorimeter, and from the standard
molar enthalpies of vaporization or sublimation, measured by Calvet microcalorimetry.
The mean values for the molar dissociation enthalpy of the nitrogen-oxygen bonds, 〈DH
m0〉(N-O), were derived for both N,N′-dioxide compounds. These values are discussed in terms of the molecular structure of the two N,N′-dioxide derivatives and compared with 〈DH
m0〉(N-O) values previously obtained for other N-oxide derivatives. 相似文献
3.
L. T. Eremenko L. B. Romanova M. E. Ivanova D. A. Nesterenko V. S. Malygina A. B. Ermeev G. V. Lagodzinskaya V. P. Lodygina 《Russian Chemical Bulletin》1998,47(6):1137-1140
NewN,N′-bis- andN,N,N′, N′-tetrakis-hydroxyalkyl-substituted 1,4-cubanedicarboxamides were synthesized. Nitration of these compounds yielded the corresponding
nitrates. The reaction of 1,4-cubanedicarboxylic acid dichloride with ethylene glycol mononitrate and glycerol dinitrate gave
ester 1,4-[R1R2CHOC(O)]2C8H6, where R1=H and R2=CH2ONO2; and R1=R2=CH2ONO2, respectively. The cardiopharmacological activity of some of the synthesized compounds was determined. This allowed us to
find for the first time cubane derivatives that exhibit this kind of biological activity. The antiischemic activity of one
of these compounds,N,N′-bis(2-nitroxythyl)-1,4-cubanedicarboxdiamide, is higher than that of the well-known Nicorandil.
For Part 2, see Ref. 1.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1169–1172, June, 1998. 相似文献
4.
Ahmad Shaabani Ali H. Rezayan Abbas Rahmati Masoumeh Sharifi 《Monatshefte für Chemie / Chemical Monthly》2006,137(1):77-81
Summary. Hantzsch 1,4-dihydropyridine compounds were synthesized efficiently in high yields at room temperature within short times in 1,1,3,3-N,N,N′,N′-tetramethylguanidinium trifluoroacetate as ionic liquid using ultrasound irradiation. The ionic liquid can be recovered conveniently
and reused efficiently. 相似文献
5.
2-Polyfluoroalkylchromones react with aliphatic 1,2-diamines to give 2,3-dihydro-1H-1,4-diazepines. A similar reaction with 1,3-diaminopropane yieldsN,N′-trimethylenebis(2-hydroxyacetophenomines) as a result of scission of the original chromones.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 817–819, April, 1999. 相似文献
6.
Salts ofN-(β-hydroxyalkyl)-N′-hydroxydiazeneN-oxides, RCH(OH)CH2N(O)=NO− M+ (R=Me, Pri, or But; and M=Li, Na, K, Ag, NH4, or Me4N), were prepared. Their alkylation with alkyl halides R′X (X=Cl, Br, or I) and dimethyl sulfate was studied. Generally, alkylation
afforded mixtures ofN-(β-hydroxyalkyl)-N′-alkoxydiazeneN-oxides RCH(OH)CH2N(O)=NOR′ andO-alkyl-N-(β-hydroxyalkyl)-N-nitrosohydroxylamines RCH(OH)CH2N(NO)OR′.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1996–2001, October, 1998. 相似文献
7.
V. A. Valiullin T. E. Ivakhnenko G. S. Borodkin Sh. G. Mkoyan S. M. Aldoshin E. P. Ivakhnenko 《Russian Chemical Bulletin》2006,55(5):860-864
Formylation of N-phthaloylglycine with the POCl3-DMF system afforded N,N,N′, N′-tetramethyl-2-(N-phthaloyl)vinamidinium perchlorate (2). X-ray diffraction study showed that molecule 2 is planar and contains two equivalent nitrogen atoms in the three-carbon vinamidinium fragment. Salt 2 undergoes transamination with primary aromatic amines to give the corresponding bis-azomethines. The reactions with hydrazines
produce substituted 4-aminopyrazoles.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 832–835, May, 2006. 相似文献
8.
M. Yu. Moskalik B. A. Shainyan U. Schilde 《Russian Journal of Organic Chemistry》2011,47(9):1271-1277
Reactions of trifluoromethanesulfonamide with α-methylstyrene, 2-methylpent-1-ene, and cycloocta-1,5-diene in the system t-BuOCl-NaI were studied. In the reaction with α-methylstyrene 1-iodo-2-phenylpropan-2-ol was the only isolated product. The
reaction with 2-methylpent-1-ene gave a mixture of N,N′-(2-methylpentane-1,2-diyl)bis(trifluoromethanesulfonamide), trifluoro-N-(2-hydroxy-2-methylpentyl)-methanesulfonamide, and N,N′-[oxybis(2-methylpentan-2,1-diyl)]bis(trifluoromethanesulfonamide). Trifluoromethanesulfonamide reacted with cycloocta-1,5-diene
to produce a mixture of 2,5-diiodo-9-(trifluoromethylsulfonyl)-9-azabicyclo[4.2.1]nonane and 2,5-diiodo-9-oxabicyclo[4.2.1]nonane;
this reaction may be regarded as the first example of direct assembly of bicyclononane skeleton. 相似文献
9.
Luu Van Boi 《Russian Chemical Bulletin》1999,48(12):2294-2298
Thiocarbamoylation of primary and secondary aliphatic amines with tetramethylthiuram disulfide in various solvents at different
temperatures was studied. At 110°C, the reactions with primary amines afforded mixed,N,N-dimethyl-N′-alkyl(cycloalkyl)thioureas and symmetricalN,N′-dialkyl(cycloalkyl)thioureas as the final products, while the reactions with secondary amines gave mixtures of dithiocarbamate
salts with “symmetrical” derivatives predominating. 相似文献
10.
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.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2296–2302, December, 2007. 相似文献
11.
Reactions ofN,N-bis(chloromethyl)amides withN,N′-diacyl derivatives of ethylenediamine (oro-phenylenediamine) result in formation of the corresponding 1,3,5-triacylated perhydro-1,3,5-triazepines (or their benzoanalogs)
or 1,3-diacylated imidazolidines (or their benzoanalogs). Reactions ofN,N-bis(chloromethyl)amides withN,N′-ditosylated trimethylenediamine occur in a similar way. The direction of the reactions depends on the type of the acyl substituents
and the strength of the bases.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2270–2273, November, 1998. 相似文献
12.
Yu Cui Yufen Hu Yanju Zhang Shaohong Yin Guoxin Sun 《Russian Journal of Inorganic Chemistry》2010,55(3):468-471
The extraction of uranyl nitrate with the novel extractant N,N′-dimethyl-N,N′-dioctylmalonamide (DMDOMA) from aqueous sodium nitrate (and nitric acid) was investigated. The extraction mechanism was
established and the stoichiometry of the main extracted species confirms to UO2(NO3)2 · DMDOMA. The IR spectral study was also made of the extracted species. Methyl substituent improves the extraction ability
of malonamide for U(VI) compared with that of N,N,N′,N′-tertrabutylmalonamide (TBMA). 相似文献
13.
N,N′-Bis[(1-methyl-3-oxobutylidene)hydrazinocarbonylethyl]-, N,N′-bis[(2,5-dimethylpyrrol-1-yl)carbamoylethyl]-, N,N′-bis(phenylureidocarbamoylethyl)-,
N,N′-bis(phenylcarbamoyl)-, N,N′-bis(phenylureidocarbamoylethyl)-, and N,N′-bis[(4,5-dihydro-5-oxo-4-phenyl-1,2,4-triazol-3-yl)ethyl]-1,4-phenylene-diamines,
and their thio analogs were obtained by the condensation of N,N′-bis-(hydrazinocarbonylethyl)-1,4-phenylenediamine with 2,4-pentanedione,
2,5-hexanedione, phenyl isocyanates, or phenyl isothiocyanates (with subsequent treatment of the obtained semicarbazides with
alkali), and carbon disulfide respectively. 相似文献
14.
V. A. Tartakovsky A. S. Ermakov N. V. Sigai O. N. Varfolomeeva 《Russian Chemical Bulletin》2000,49(6):1079-1081
Symmetrical and unsymmetricalN,N′-dialkylmethylenebis(nitramines) were obtained fromN-alkylsulfamates by condensation with formaldehyde and subsequent nitration.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1085–1087, June, 2000. 相似文献
15.
B. S. Fedorov N. I. Golovina G. V. Strukov V. V. Kedrov G. N. Boiko G. V. Shilov L. S. Barinova R. F. Trofimova L. O. Atovmyan 《Russian Chemical Bulletin》2000,49(3):566-568
The reaction ofN-2-nitroxyethylpicolinamide with PdCl2 afforded the new complexcis-[2-(2-pyridyl)-2-oxazoline-N,N′]dichloropalladium(u). The structure of this complex was established by X-ray diffraction analysis.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 561–563, March, 2000. 相似文献
16.
A new approach is suggested for determining the kinetic parameters and rate constants of the elementary steps of reversible
chain reactions having self-acceleration periods due to the long time required for the concentrations of the chain-carrier
radicals to reach their steady-state values. This approach is illustrated by the example of the reversible chain reaction
between N,N′-diphenyl-1,4-benzoquinonediimine and 2,5-dichlorohydroquinone in chlorobenzene. The disappearance rate of one of the initial
reactants, N,N′-diphenyl-1,4-benzoquinonediimine, at the inflection point of its disappearance curve, is considered as the basic kinetic
characteristic of the reaction. The empirical function y = aexp(bt
c
) + d, where a, b, c, and d are the fitted parameters (b < 0, c > 1), is suggested for approximating the S-shaped kinetic curves and for calculating the reaction rate. The rate constants
of the elementary steps are preferably derived from experimental data obtained at equal concentrations of the initial reactants,
and also product additions when their effect on the reaction rate is studied. The effective rate constant of chain termination
is derived from the time to reach the steady state. The results obtained in this way are compared with earlier data obtained
using the “initial” reaction rates calculated by means of exponential approximation of portions of N,N′-diphenyl-1,4-benzoquinonediimine disappearance curves after the inflection point. 相似文献
17.
Ahmad Shaabani Ali H. Rezayan Abbas Rahmati Masoumeh Sharifi 《Monatshefte für Chemie / Chemical Monthly》2006,56(7):77-81
Hantzsch 1,4-dihydropyridine compounds were synthesized efficiently in high yields at room temperature within short times in 1,1,3,3-N,N,N′,N′-tetramethylguanidinium trifluoroacetate as ionic liquid using ultrasound irradiation. The ionic liquid can be recovered conveniently
and reused efficiently. 相似文献
18.
Theoretical study on the hydrolysis mechanism of N,N -dimethyl- N ′-(2′,3′-dideoxy-3′-thiacytidine)formamidine 总被引:1,自引:0,他引:1
The hydrolysis mechanisms of N,N-dimethyl-N′-(2′,3′-dideoxy-3′-thiacytidine)formamidine (FA-3TC) in the gas phase and in aqueous solution were studied by use of the
density functional theory B3LYP/6-31+G(d, p) method. Two possible reaction pathways in the title reaction were considered.
In one pathway water attacks the C=N double bond first (path A) while in the other water attacks the C-N single bond first
(path B). The calculated results indicate that the first step in both pathways is the rate-limiting process and path A is
more favorable than path B in the gas phase. The effect of solvent water on the title reaction was assessed at the B3LYP/6-31+G(d,
p) level of theory based on the polarizable continuum model (CPCM). In water the first mechanism (path A) is also favored.
Supported by the National Natural Science Foundation of China (Grant Nos. 20473055 and 20773089) and the Scientific Research
Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (Grant No. 20071108-18-15) 相似文献
19.
Reactions ofN-nitramines and their trimethylsilyl derivatives withN,N-bis(trimethylsilyloxy)enamines
S. L. Ioffe L. M. Makarenkova Yu. A. Strelenko I. V. Bliznets V. A. Tartakovsky 《Russian Chemical Bulletin》1998,47(10):1989-1991
Trimethylsilyl derivatives of methyl- and ethylnitramine react asN-centered nucleophiles with 2-N,N-bis(trimethylsilyloxy)aminopropene to give trimethylsilyl derivatives of hitherto unknown α-(N-nitro)alkylamino-substituted acetone oximes. As an ambident nucleophile, nonsubstituted methylnitramine reacts with the same
enamine to give both a product of N,C-corss-coupling and a product of O,C-cross-coupling,viz., N′-methyl-N-[(2-trimethylsilyloxyimino)propoxy]diazeneN-oxide.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2045–2047, October, 1998. 相似文献
20.
B. S. Fedorov N. I. Golovina V. V. Arakcheeva M. A. Fadeev G. V. Strukov V. V. Kedrov G. V. Shilov L. O. Atovmyan 《Russian Chemical Bulletin》1999,48(8):1584-1586
The reaction ofN,N′-bis(2-nitroxyethyl)pyridine-2,6-dicarboxamide with PdCl2 afforded previously unknowncis-(N-2-nitroxyethylpicolinamide-N,N′)dichloropalladium(II) andcis-[2-(2-pyridyl)-2-oxazoline-N,N′]dichloropalladium(II), which were isolated as a cocrystallizate of the molecular compounds. Its structure was established
by X-ray diffraction analysis.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1604–1606, August, 1999. 相似文献