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1.
Zusammenfassung Aus den entsprechenden -Bromestern werden durch Umsetzung mit Natriumnitrit die -Oximinodicarbonsäuredimethylester C7 und C9 und der , -Dioximinoazelainsäuredimethylester erhalten. -Methyladipinsäure wird zum Gemisch aus -Bromund -Bromester umgesetzt. Mit Natriumnitrit wird -Nitro-und -Oximino--methyladipinsäuredimethylester erhalten.
The -oximino dicarboxylic dimethyl esters of C7 and C9 and the , -dioximino azelaic acid dimethyl ester are received from the corresponding -bromo esters by reaction with sodium nitrite. -Methyladipic acid is reacted with bromine to a mixture of the -bromo and -bromo ester. Reaction with sodium nitrite gives the -nitro ester and the -oximino ester of -methyl adipic acid.


5. Mitt.:H. Reinheckel, Mh. Chem.98, 1217 (1967).  相似文献   

2.
A study was made of the difference occurring in ammonium nitrate during investigation by DTA and by DSC. The results show that the DTA of ammonium nitrate (p.a.) is accompanied by the crystal transformation IV III II I and melting. During DSC investigation of the same ammonium nitrate samples, the salt undergoes the transformations IV III and IV II in parallel; then follow the crystal transformations III II I and melting. The investigation conditions and the history of the samples do not essentially influence the crystal transformations during thermal analysis.
Zusammenfassung Bei DTA und DSC von Ammoniumnitrat zu beobachtende Unterschiede wurden untersucht. Bei der DTA von p.a. Ammoniumnitrat verlaufen die Kristallumwandlungen IV III II I sowie der Schmelzvorgang. Während der DSC der gleichen Ammoniumnitratproben verlaufen die Übergänge IV III und IV II parallel, worauf die Kristallumwandlungen III II I und der Schmelzvorgang folgen. Die experimentellen Bedingungen und die Vorgeschichte der Proben hat keinen wesentlichen Einfluß auf die während der thermischen Analyse verlaufenden Kristallumwandlungen.

. ( ..) IV III II I . , IV III IV II - , III II ar I . .
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3.
At 148–298 K, the rate constant for the reaction of methane molecules excited into bending vibration with atomic chlorine does not exceed by more than 30 times the corresponding constant for methane in thermal equilibrium. Consequently, at low temperatures and thermal equilibrium the reaction of methane with atomic chlorine proceeds through the vibrational ground state of methane.
, 148–298°K , , 30 , . , .
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4.
Polyacrylales of Fe, Cr, Ni, Co and Mn were synthesized by the reaction of poly(sodium)acrylatc with metal halides. The salts obtained were investigated by thermal analysis. During heating in argon or air, all the salts behaved in a similar way. The initial decomposition temperature of the investigated salts increased in the following sequence: Fe<Cr<Ni<Co<Mn. The solid residues of the decompositions of the salts were also analysed.
Zusammenfassung Polyacrylate von Fe, Cr, Ni, Co und Mn wurden durch Reaktion von Natriumpolyacrylat mit den entsprechenden Metallhaliden synthetisiert. Die erhaltenen Salze wurden thermoanalytisch untersucht. Beim Aufheizen in Argon und Luft verhalten sich alle Salze ähnlich. Die Temperatur, bei der die Zersetzung einsetzt, steigt in folgender Reihenfolge an: Fe < Cr < Ni < Co < Mn. Die festen Rückstände der Zersetzung der Salze wurden ebenfalls analysiert.

, , , . , , . Fe<Cr<Ni<Co<Mn. .
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5.
Infrared spectra of both fresh and reductively activated V2O5 and V2O5–MoO3 catalysts were recorded and compared with the results of catalytic measurements. The results indicate that the presence of V=O double bonds in the catalytically active mass is not essential for the selective oxidation of benzene to maleic anhydride.
, V2O5 V2O5–MoO3. . , V=O .
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6.
With excess acyl halide 1-methyl-3-acyl-2-(1-methyl-2-benzimidazolyl)-4-benzimidazoline is converted to an unstable 1-methyl-3-acyl-2-(1-methyl-3-acyl-4-benzimidazolin-2-yl)benzimidazolium chloride, which undergoes intramolecular redox cleavage with the formation of 1,1-dimethyl-2,2-dibenzimidazolyl and an aldehyde and dissociates at the C-C bond that connects the benzimidazolium and benzimidazoline fragments into a carbene yield and a 1-methyl-3-acylbenzimidazolium chloride.See [1] for communication 1.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 339–342, March, 1987.  相似文献   

7.
    
The methiodide of 1,3, 4-(1-hydroxy-3-methyl-4-ethylidenepentan1, 3, b, 5-triyl]-3,4, 5, 6-tetrahydro--carboline is synthesized.For part XVIII see [1].  相似文献   

8.
Differential heats of benzene adsorption at 293 K on Mg2+, Ca2+, Sr2+, Ba2+ metakaolinites at surface coverages of =0.2 have been measured in a Calvet microcalorimeter. An inverse dependence of benzene and cuene adsorption heats on monocationic metakaolinites has been revealed. The presence of two types of adsorption centers is predicted.
293 Mg2+-, Ca2+-, Sr2+-, Ba2+- 0,2. . .
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9.
Dehydroxylation of an American nontronite (Manito) was followed via records of isothermal and dynamic thermogravimetry. Analysis of the isothermal weight-change curves (673-753 K). was performed with the procedure suggested by Hancock and Sharp. A fourteen-kinetic equation procedure was employed for analysis of the non-isothermal weight change in the range 623–1023 K. (A second-order decomposition equation seems to fit the dehydroxylation better under these conditions). The activation energies associated with the isothermal and nonisothermal processes are 118.8 and 136.8 kJ/mol–1, respectively.
Zusammenfassung Anhand isothermer und herkömmlicher Thermogravimetrie wurde die Dehydroxylierung eines amerikanischen Nontronites (Manito) verfolgt. Die isothermen TG-Kurven (673–753 K) wurden mittels der von Hancock und Sharp (1972). Ein kinetisches Vierzehngleichungsverfahren wurde zur Analyse der nichtisothermen TG-Kurven im Bereich 623–1023 K angestellt. Einer Dehydroxylierung unter diesen Bedingungen scheint eine Zersetzungsgleichung zweiter Ordnung besser zu entsprechen. Die Aktivierungsenefgie für die isothermen bzw. nichtisothermen Prozesse beträgt 118,8 bzw. 136,8 kJ/mol.

(). (673–753 ) . , 623–1023, . . , , 118,8 136,8 /.
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10.
Kinetic regularities of ethylene oxidation to ethylene glycol monoacetate (EGMA) in the presence of a PdCl2 and Fe(NO3)3-containing catalytic system has been studied to clarify the peculiarities of the mechanism of this reaction.
() .
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11.
To obtain benzodioxazole analogs of the polypyromellitimides and polymers with alternating pyromellitimide and benzodioxazole links, we have synthesized 2,6-di(paminophyl)benzo[1,2-d5,4-d]dioxazole (I), 2,6-di[p-(p-aminophenoxy)phenyl]benzo-[1,2-d5,4-d]dioxazole (II), N,N-di(p-chloroformylphenyl)pyromellitdiimide (III) and N,N-di(p-chloroformylphenyl)-2,5-dimethoxycarbonyl terephthalamide (IV). Derivatives modelling the polymers mentioned above have been synthesized from the diamines mentioned, and also from 4,6-diaminoresorcinol.Translated from Khimiya Geterotsiklicheskikh Soedinenii, Vol. 6, No. 6, pp. 739–743, June, 1970.  相似文献   

12.
7,7-Dichloro-2,2-dicarbethoxybis (5-indolyl) methane has been synthesized by cyclization of the 3,3-dichloro-4,4-diphenylmethanedihydrazone of ethyl pyruvate. Subsequent hydrolysis and decarboxylation of the corresponding diacid gave the unsubstituted 7,7-dichlorobis (5-indolyl) methane. The syn-syn, syn-anti, and anti-anti forms of 3,3-dichloro-4,4-diphenylmethanedihydrazone of ethyl pyruvate have been separated and characterized.For Communication 25, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1062–1065, August, 1988.  相似文献   

13.
Summary The polarographic procedure can be used for the quantitative analysis of all the aminoazobenzenes tested in this study as indicated by proportionality between diffusion current and concentration. There is no significant correlation between the half-wave potential and carcinogenic potency for rat liver for three monosubstituted and seven disubstituted derivatives ofp-dimethylaminoazobenzene. These ring-substituted azocarcinogens rank from weak to very strong for carcinogenic potency against rat liver. Also aminoazobenzenes such as the noncarcinogenic 4-amino-4-dimethylaminoazobenzene and the carcinogenic N,N-dimethyl-4-amino-N-formyl-N-methyl-4-aminoazobenzene and N,N-dimethyl-4-amino-N-acetyl-N-methyl-4-aminobenzene have similar have-wave potentials. On the other hand, the noncarcinogenic 4-aminoazobenzene, 4-amino-N-methyl-4-aminoazobenzene and N-methyl-4-amino-N-methyl-4-aminoazobenzene have half-wave potentials that are about 100 mv more negative than that of all other aminoazobenzenes discussed in this report.
Zusammenfassung Die Proportionalität zwischen Konzentration und Stromdurchfluß bietet die Grundlage zur polarographischen Bestimmung aller in dieser Arbeit geprüften Aminoazobenzole. Zwischen dem Halbwellenpotential und der carcinogenen Wirkung gegenüber Rattenleber besteht bei drei monosubstituierten und sieben disubstituierten Derivaten desp-Dimethylaminoazobenzols keine signifikante Korrelation. Diese ringsubstituierten Azocarcinogene zweigen schwache bis sehr starke carcinogene Wirkung gegenüber Rattenleber. Aminoazobenzole wie das nicht-carcinogene 4-Amino-4-dimethylaminoazobenzol und die carcinogenen Verbindungen N,N-Dimethyl-4-amino-N-formyl-N-methyl-4-aminoazobenzol und N,N-Dimethyl-4-amino-N-acetyl-N-methyl-4-aminoazobenzol haben ähnliche Halbwellenpotentiale. Andrerseits ist das Halbwellenpotential der nicht-carcinogenen Verbindungen 4-Aminoazobenzol, 4-Amino-N-methyl-4-aminoazobenzol und N-Methyl-4-amino-N-methyl-4-aminoazobenzol ungefähr um 100 mV negativer als das aller anderen hier behandelten Aminoazobenzole.
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14.
Summary Cobalt(II) and nickel(II) halide complexes of the ligands 2-(2-methyl-8-quinolyl)benzoxazole (mqbo), 2-(2-methyl8quinolyl)benzimidazole (mqbi) and 2-(4-methyl-8-quinolyl)benzimidazole (mqbi) were synthesized and characterized by analytical, thermogravimetric, conductivity and magnetic data, and i.r. and electronic spectra.The ligands are bidentate N-donors yielding complexes where the coordination geometry depends on the metal ion and steric hindrance. All the cobalt complexes have formula [CoL2X2] and distorted tetrahedral geometry. Different types of nickel compounds were obtained: i) complexes of formula NiLX2 · n H2O (or EtOH) (L = mqbo or mqbi; n=0–1.5) which arepseudo-tetrahedral or five-coordinate and ii) complexes NiL2X2 · n H2O (L = mqbi, n=3 or 4) where the metal is bound to four nitrogen atoms and the overall coordination geometry is tetragonal. The structural changes occurring after removal of water or alcohol from the complexes are also reported.  相似文献   

15.
Summary Palladium(II) and platinum(II) complexes [MLX2], where L=2-(4-methyl-2-pyridyl)benzimidazole (mpbi), 2-(4-methyl-2-pyridyl)benzoxazole (mpbo), 2-(4-methyl-2-quinolyl)benzoxazole (mpbo), 2-(4-methyl-8-quinolyl)benzoxazole (mq'bo), X=Cl. Br, together with M(mqbo)2Br2 and Pt2(mpbt)Cl4, where mpbt=2-(4-methyl-2-pyridyl)benzthiazole, have been synthesized and characterized by conductivity and magnetic measurements as well as by i.r. and electronic spectra. The ligands are bidentate chelates through the pyridine or quinoline and isoxazole or imidazole nitrogen atoms. The [MLX2] derivatives arecis, square planar.  相似文献   

16.
A general and repetitive method to determine the base strength and number of basic sites of catalysts with low surface area is reported. The nature of the titrating agent is discussed. The nature of the active sites of a Ba(OH)2 catalyst with low surface area is discussed.
. . Ba(OH)2, .
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17.
Aniline reacts with 2,2,6,6-tetraphenyl-4,4-bipyrilium perchlorate to form 1,1,2,2,6,6-hexaphenyl-4,4-bipyridine perchlorate. A relatively stable cation radical is formed in the first stage of electrochemical reduction of this compound, which has been examined by ESR, where there are splittings from two nitrogen nuclei and the four protons in the 3,3,5,5 positions: aN=0.38; aH=0.14 mT.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, No. 1, pp. 61–64, January–February 1992.  相似文献   

18.
    
The rates of the gas phase elimination of o-methyl and o-methoxy from -phenylethyl acetates were studied in a static system over the temperature range 360.0–410.1°C and pressure range 39–177 Torr. The reactions in seasoned vessels and in the presence of cyclohexene inhibitor, are firstorder, homogeneous and unimolecular to give acetic acid and the corresponding o-substituted styrene. The effect of several substituents at the orthoposition of the benzene ring in -phenylethyl acetate is discussed in terms of electronic and steric factors.
- - - 360–410, 7° 39–177 . , , , - . - - .
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19.
The energy of interaction between a methanol molecule and an MoO 4 2– group of the Fe2(MoO4)3 and Ga2(MoO4)3 lattice, and the force constant of the C–H bond calculated by the INDO method show that the deformation of MoO 4 2– tetrahedra leading to the displacement of Mo6+ to the edge attacked, increase the stabilizing contribution to the energy and decrease the C–H force constant. This effect is maximal at 1Mo–O2 Å.
INDO MoO 4 2– , - Fe(MoO4)3 Ga2(MoO4)3 C–H, , MoO 4 2– , Mo6+ , C–H. 1Mo–O2 Å.
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20.
1-Methyl-2-(5-methyl-2-selenienyl)benzimidazole was synthesized and subjected to electrophilic-substitution reactions: nitration, bromination, sulfonation, chloromethylation, formylation, and acylation. The substituent usually enters the 4 position of the selenophene ring, but nitration with acetyl nitrate leads to a mixture of 5-nitro and 4-nitro derivatives. Oxidation of 2-selenienylbenzimidazole with potassium permanganate leads to the 5-carboxy derivative, while oxidation with selenium dioxide leads to the 5-hydroxymethyl and 5-formyl derivatives.See [1] for Communication 7.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1636–1639, December, 1987.  相似文献   

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