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1.
The reaction of the acetylacetonyl radical (generated from acetylacetone by the action of manganese acetate) with vinylacetylene, 2-vinylfuran, and butadiene Was studied. The reaction proceeds nonregioselectively with vinylacetylene: 3-acetyl-2-methyl-5-ethynyl- and 3-acetyl-2-methyl-5-(4-acetyl-5-methyl-2-furyl)-4,5-dihydrofurans in a ratio of 12.2 were isolated. The principal products in the reaction with 2-vinylfuran and butadiene were 3-acetyl-2-methyl-5-(2-furyl)- and 3-acetyl-2-methyl-5-vinyl-4,5-dihydrofurans.Communication 62 from the series Reactions of unsaturated compounds. See [1] for communication 61.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 884–887, July, 1980.  相似文献   

2.
Pyrimidines     
The reaction of substituted 3-methyl-5-pyrazolones with arylidenebisureas has been studied. Substituted spiro[pyrazole-4, 5-pyrimidines] have been obtained from 1-phenyl- and 1-benzyl-3-methyl-5-pyrazolones. When only one hydrogen atom was present in the ring of the 3-methyl-5-pyrazolone, the corresponding -ureidobenzyl derivative was obtained.For communication XI see [1].  相似文献   

3.
Initial stage of the reaction of CCl4 with V2O5 has been studied by MS and XPS techniques. According to the proposed mechanism dissociatively chemisorbed CCl4 transforms to CO2 via adsorbed COCl2, while surface vanadium atoms involved are gaining step by step two chlorine atoms before the formation of the volatile end-product VOCl3.
CCl4 V2O5 . - CCl4 CO2 COCl2, VOCl3.
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4.
Twelve new complexes NH4[Co(DH)2(SO3)(amine)]·t H2O (DH 2=dimethylglyoxime) have been synthesized and characterized. Their i.r. spectra show the SO3 to be co-ordinated to the Co atom through the S atom. The thermal decompositions of a series of derivatives of this type have been investigated with a derivatograph. The first process is an endothermic dehydration reaction, occurring in a single stage or in two successive ones. The loss of the crystallization water is followed by another endothermic reaction, without a clear stoichiometry, which is referred to as deamination. At higher temperatures, exothermic pyrolysis processes occur. From the TG curves, kinetic parameters have been derived for the dehydration and deamination reactions.
Zusammenfassung Zwölf neue Komplexe der allgemeinen Formel NH4[Co(DH)2(SO3)(amin)]·t H2O (DH=Dimethylglyoxim) wurden synthetisiert und charakterisiert. Die IR-Spektren zeigen, daß SO3 über das S-Atom koordinativ an das Co-Atom gebunden ist. Die thermische Zersetzung einer Reihe von Derivaten dieses Typs wurde mittels eines Derivatographen untersucht. Der erste Prozeß ist die in einem einzigen oder in zwei aufeinander folgenden Schritten verlaufende endotherme Dehydratisierung. Auf die Abgabe des Kristallwassers folgt eine andere endotherme Reaktion unklarer Stöchiometrie, die als Deaminierung bezeichnet wird. Bei höheren Temperaturen verlaufen exotherme Pyrolyseprozesse. Aus den TG-Kurven wurden kinetische Parameter für die Dehydratisierung und die Deaminierung bestimmt.

NH4Co(DH)2(SO3)(a)]·tH2O, DH 2 — . , . . , . «». . .
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5.
The reactions of TMA4Ge4S10 (TMA=tetramethylammonium), Cu(NO3)23H2Oand 4,4-bipy under hydrothermal environment result in the formation of (H2bipy)2Ge4S10(bipy)7H2O (1), which has been structurally characterized by single crystal X-ray analysis. The 3-D structure of 1 can be viewed as an inorganic-organic hybrid supramolecular hydrogen-bonding (hydrogen bonds: O–HO, N–HN, C–HO, N–HO, and O–HS) and - stacking network containing Ge4S4– 10 clusters and novel [H2bipybipyH2bipy] trimers.  相似文献   

6.
A standard method was developed for investigation of the adsorbed water in ionexchange resins. The previously-dried anion-exchange resins in Cl, SO4 and HSO4 form were investigated by simultaneous TG, DTG and DTA measurements (derivatograph), and the evolved gases were passed through the continuous and selective water detector system developed earlier.It was found that in the case of SO4 and HSO4-form resins two types of water binding (loosely and strongly-bound water) could be distinguished. The second step, the stronglybound water step, could not be observed in the DTG curves, because the release of the bound water and the decomposition of the fixed ionic group take place simultaneously. As the two types of water peaks strongly overlap, their quantitative evaluation was carried out by graphical analysis.
Zusammenfassung Eine Standardmethode wurde zur Untersuchung des absorbierten Wassers in Ionenaustauscherharzen entwickelt. Die vorhergehend getrockneten Anionenaustauscherharze in Cl, SO4 und HSO4-Form wurden durch die Methode der simultanenTG, DTG und DTA-Messungen untersucht und die entwickelten Gase das durch früher entwickelte kontinuierliche und selektive Wasserdetektorsystem geleitet.Es wurde gefunden, daß in dem Falle der Harze der SO4 und HSO4-Form zwei Typen von Wasser (lose und stark gebundenes Wasser) unterschieden werden können. Die zweite Stufe, die sogenannte «Stark-gebundenes-Wasser»-Stufe konnte an den DTG-Kurven nicht beobachtet werden, da die Freisetzung des gebundenen Wassers und die Zersetzung der fixierten ionischen Gruppe simultan erfolgt. Da die zwei Typen der Wasser-Peaks stark überlappen, wurde ihre quantitative Auswertung under Anwendung einer graphischen Analysenmethode durchgeführt. Die auf äquivalentes Harz bezogenen Angaben in H2O-Mol waren wie folgt: für Harz in der Cl-Form, 1.464, für die Harze in SO4 und HSO4-Form waren die Werte von lose und stark gebundenem Wasser 1.753 und 0.357, bzw. 2.094 und 0.451.

Résumé On a mis au point une méthode type pour étudier l'eau adsorbée sur les résines échangeuses d'ions. On a étudié par TG, TGD et ATD simultanées les résines échangeuses d'anions sous la forme Cl, SO4 et HSO4 préalablement séchées et on a fait passer les gaz dégagés dans le système détecteur d'eau continu et sélectif mis au point précédemment.Dans le cas des résines sous la forme SO4 et HSO4, on a trouvé que deux types d'eau (faiblement et fortement liée) pouvai ent être distingués. La deuxième étape, dénommée étape de l'eau fortement liée, ne peut être observée sur les courbes TGD, car le dégagement de l'eau liée et la décomposition du groupe ionique fixé ont lieu simultanément. Comme les deux types de pics dus à l'eau se recouvrent fortement, on a effectué leur évaluation quantitative à l'aide d'une méthode d'analyse graphique. Les données trouvées, exprimées en moles d'H2O sur résine équivalente, sont les suivantes: pour la résine sous forme Cl 1.464, pour les résines sous formes SO4 et HSO4 les types d'eaux faiblement et fortement liées donnent respectivement 1.753, 0.357 et 2.094, 0.451.

, . Cl, SO4 HSO4 , , , , . , SO4 HSO4 - , : . , , , . , . , , : Cl-- 1,464, SO4 HSO4-- , ,- 1.753; 0.357 2.094; 0.451.
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7.
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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8.
Boiling 2-methyl-4-oxo-3,4-dihydrothionaphtheno[3,2-d]-pyrimidine with phosphorus oxychloride gives 2-methyl-4-chlorothionaphtheno [3,2-d]pyrimidine (II), in which the chlorine atom is mobile. Nucleophilic substitution of the mobile chlorine atom in compound II gives the 4-ethoxy,4-(N-piperidino),4-(N4-methyl-N-piperazino), 4-[2-(diethylamino)ethylamino],4-3-(diethylamino)-2-hydroxypropylamino]substituted derivatives.  相似文献   

9.
The reaction of the sodium salt of 2-mercapto-6-methyluracil with , -dibromoalkanes Br(CH2)Br (n=1,4,5,6) has given the corresponding , -bis(4-hydroxy-6-methyl-2-pyrimidinylthio) alkanes. The reaction of the same salt with 1,2-dibromoethane gave 7-methyl-5-oxo-2,3,4,5-tetrahydrothiazolo[3,2-a]pyrimidine and 5-methyl-7-oxo-2,3,4,7-tetrahydrothiazolo[3,2-a]pyrimidine, and its reaction with 1,3-dibromopropane led to 8-methyl-6-oxo-3,4,5,6-tetrahydro-2H-pyrimidino[2,1-b]-1,3-thiazine.  相似文献   

10.
An integrated Xray diffraction study was performed on polycrystals and single crystals of three new isostructural phases with general formula Ag4A2[M(NO2)4]3 (M = Pd, Pt; A = K, Rb). Data on the crystal structure solution (CAD4 diffractometer, MoK radiation, graphite monochromator = 2–30° are presented. In one crystallographically independent [M(NO2)4]2- complex anion, the planar square coordination of the central atom is completed to 4 + 2 by two oxygen atoms at a distance of 3.02–3.12 in the other anion, it is completed to 4 + 1 + 1 by an oxygen atom at a distance of 3.12–3.30 and an Ag+ cation at a distance of 3.04–3.11 . Part of the Ag+ cations form Ag - Ag dimers with a distance of 3.03–3.07. Crystalchemical analysis of known structures containing [Pd(NO2)4]2- complex anions was performed. It has been established that in none of the cases do any of the possible limiting configurations occur.  相似文献   

11.
It has been established that o-xylene chemisorption on coals requires the presence of nucleophylic surface sites. Selectivity in o-xylene oxidation over carbon catalysts depends not only on their structure, but also on their surface functional groups.
, - . - , .
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12.
The Beckmann rearrangement of cyclohexanone oxime to caprolactam has been studied in the vapor phase over fluorinated alumina catalysts containing 1 to 61 wt. % F. Addition of fluorine enchances the catalytic activity of Al2O3. Selectivity to caprolactam shows a maximum in the fluorine range 11–31%. It is likely that an optimum distribution of Lewis and Brönsted acidic sites on the catalyst surface is responsible for the high selectivity observed at intermediate fluorine contents. Addition of water to the gas phase causes a decrease in selectivity.
, 1 61 . % . Al2O3. 11–31%. , , . .
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13.
This paper presents a final discussion on studies of solutions of electrolytes in molten acetamide. These studies deal with cryoscopic and ultrasonic (by shear waves) techniques and reveal the complexity of the behaviour of these systems due to strong ion-solvent interactions.
Zusammenfassung Die über Lösungen von Elektrolyten in geschmolzenem Acetamid ausgeführten Untersuchungen werden diskutiert. Diese Untersuchungen erstrecken sich auf kryoskopische und Ultraschall-Methoden und vermitteln ein Bild von der durch starke Ionen-Lösungsmittel-Wechselwirkungen bedingten Komplexität des Verhaltens dieser Systeme.

. , - - .


Thanks are due to CNR and MPI (Rome) for financial support, and to R. Borgarucci for technical assistance.  相似文献   

14.
The introduction of K2O and Bao additives into supported V–Sb–Bi oxide catalysts enhances their activity in ammoxidation of xylenes. Bond energy and inhomogeneity character of surface oxygen, oxidation states and relative contents of metal cations remain practically unchanged, whereas the concentration of basic sites significantly increases.
V–Sb–Bi . , , .
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15.
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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16.
The promoting effect of TiO2 on CH4 formation from CH3OH decomposition has been investigated. Hydrogen and CO are products of CH3OH decomposition which can subsequently react to produce CH4. We observe an enhancement in this secondary reaction when the support is TiO2. This enhancement is lost after a high temperature reduction.
TiO2 CH4 CH3OH. CH3OH CO, , CH4. TiO2 . , , .
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17.
Zusammenfassung In B-Tri(dimethylamino)boroxin zeigt — im Gegensatz zum B-Trimethoxyboroxin — die B–O-Hauptbande nur geringe Kopplung mit CH3-Deformationsschwingungen. Die B–N-Valenzbande tritt hingegen mit sCH3 in Wechselwirkung, wodurch Banden mit gemischtem Schwingungscharakter entstehen. In der deuterierten Verbindung liegt BN verkoppelt mit BO bei 1461 cm–1
In B-Tri(dimethylamino)boroxin coupling between the B–O ring stretching main-band and CH3 is weak in contrast to B-trimethoxyboroxine. Interference between BN and CH3 leads to bands of mixed character, one of them is above 1500 cm–1. In [(CD3)2NBO] BN coupled with BO is at 1461 cm–1.


Mit 2 Abbildungen  相似文献   

18.
The fundamental possibility of carrying out the asymmetric synthesis of 4-piperidones on the basis of the transamination of 1-substituted 2-methyl-4-piperidone methiodides by optically active -phenylethylamine was demonstrated; the optical yield of the asymmetric transamination is 50%. The occurrence of asymmetric synthesis was confirmed by the isolation of enantiomers of 2-methyl-4-piperidol by reduction of the individual diastereomers of 1--phenyl-ethyl-2-methyl-4-piperidone to the corresponding 4-piperidols with subsequent removal of the chiral substituent attached to the nitrogen atom.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1378–1382, October, 1985.  相似文献   

19.
Transformations of 2-methyl-2-propanol, 2-methyl-2-butanol, 2-methyl-2-pentanol, 1-methyl-1-cyclohexanol, and 1-ethyl-1-cyclohexanol in the presence of tetraaquapalladium(II) ions in perchloric acid madium were studied. It was found that the reactions give rise to palladium(II) -allyl complexes. The reaction rate increases and the yield of the corresponding -allyl complex decreases with increasing hydrocarbon chain length. Addition of iron(III) ions to the systems essentially increases the yield of palladium -allyl complexes. The olefin formed from the corresponding tertiary alcohol participates in the formation of the palladium -allyl complex. Oxidation of 2-methyl-2-butanol with tetraaquapalladium(II) ions gives the isomeric palladium -allyl complexes [Pd(3-(CH3)2CCHCH2)bpy]ClO4 and [Pd(3-(CH2C(CH3)CHCH3))bpy]ClO4, which were isolated using 2,2'-bipyridyl and characterized by 1H and 13C NMR spectroscopy.  相似文献   

20.
5-Methyl-4,5-dihydro-3H-spiro[benzo-2-azepine-3,1-cyclohexane] N-oxide was rear- ranged into 5-methyl-1-oxo-1,2,4,5-tetrahydro-3H-spiro[benzo-2-azepine-3,1-cyclohexane]. The latter was used for the synthesis of spiro{triazolo[3,4-a]- and-tetrazolo[5,1-a]benzo-2- azepinecyclohexanes}.Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1647–1651, August, 2004.  相似文献   

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