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1.
Crystals of the [(H3NCH2CCCCCH2NH3)]Cu2Cl4 -complex, formed in the oxidative dimerization of propargylammonium cations, were obtained by ac electrochemical synthesis from CuCl2 · 2H2O and propargylammonium chloride ([CCCH2NH3]Cl) and studied by X-ray diffraction analysis (DARCh automated diffractometer, MoK radiation, /2 scan mode; 2275 reflections with F 4(F), R = 0.048). Crystals are monoclinic: space group B2/b, a = 19.591(6) Å, b = 7.299(3) Å, c = 8.636(3) Å, = 106.83(3)°, Z = 4. The structure consists of individual [(H3NCH2CCCCCH2NH3)]Cu2Cl4 moietes united through the elongated Cu···Cl contacts (2.827(5) Å) into chains oriented along the [010] direction. The bond of the centrosymmetric propargylammonium dimer is -coordintated by copper(I) atom and is elongated to 1.227(6) Å.  相似文献   

2.
Hydrogen-oxygen titration and carbon monoxide chemisorption of silica supported palladium have been investigated, using the pulse chromatographic technique. An excellent agreement between metal surface areas derived from both methods was observed.
H2–O2 . , .
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3.
Kinetics of methane interaction with acetylene on Ziegler-Natta type organonickel catalysts has been studied. The reaction is first order with respect to methane. The kinetic isotope effect amounts to KCH 4/KCD 4=1.5 and KC 2H2,CH4,H2/KC 2D2,CD4,D2=2.0.
-. -. KCH 4/KCD 4, KC 2H2,CH4,H2/KC 2D2,CD4,D2 1,5; 2,0. .
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4.
The composition of products from the interaction of ethylene with some o oxidants, catalyzed by palladium acetate in acetic acid has been studied, An assumption is made on the possible reason for the influence of such oxidants on the selectivity of formation of ethylene glycol ethers.
, , . .
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5.
The thermal decomposition of Cu(I) phosphine complexes of the general types (CuXPPh3)4, [CuX(PPh3)2] and [CuX(PPh3)3] was investigated.The thermal decomposition of (CuXPPh3)4, where X denotes Cl, Br, I, NO 3 and PPh3=P(C6H5)3, occurs with formation of a phosphine oxide intermediate. For the remaining complexes this intermediate was not proved in the thermal decomposition.
Zusammenfassung Die thermische Zersetzung der Cu(I)-Phosphinkomplexe vom allgemeinen Typ (CuXPPh3)4 und [CuX(PPh3)2], wie auch [CuX(PPh3)3] wurde untersucht. Die thermische Zersetzung von (CuXPPh3)4, wobei X=Cl, Br, I und NO 3 bedeutet und PPh3=P(C6H5)3, verläuft unter Bildung eines Phosphinoxid Zwischenproduktes, bei den übrigen Komplexen konnte dieses im Laufe der thermischen Zersetzung nicht nachgewiesen werden.

Résumé On a étudié la décomposition thermique des complexes phosphine-Cu(I) de formule générale (CuXPPh3)4, [CuX(PPh3)2], [CuX(PPh3)3]. La décomposition thermique de (CuXPPh3)4, où X désigne Cl, Br, I et NO 3 , et PPh3=P(C6H5)3, s'effectue avec formation d'un oxyde de phosphine intermédiaire; avec les autres complexes, cet intermédiaire n'a pas été mis en évidence au cours de la décomposition thermique.

(CuXPPb3)4 [CuX(PPh3)2] [CuX(PPh3)3]. (CuXPPh3)4, X=Cl, Br, I, NO 3 , PPh3=(65)3 . .
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6.
Results on the thermal decomposition of iron(II) sulphate heptahydrate in the presence of basic magnesium carbonate are presented and discussed. These results are compared with those for the mixture of iron(II) sulphate heptahydrate with basic beryllium carbonate. While no reaction occurs between the components in the case of basic beryllium carbonate, basic magnesium carbonate reacts readily with iron(II) sulphate heptahydrate.
Zusammenfassung Bei der in Gegenwart von basischem Magnesiumcarbonat erfolgten thermischen Zersetzung von Eisen(II)-sulfat-Heptahydrat erhaltene Ergebnisse werden beschrieben, diskutiert und mit denen verglichen, die in Gegenwart von Berylliumcarbonat erhalten wurden. Im Gegensatz zu basischem Berylliumcarbonat reagiert basisches Magnesiumcarbonat mit Eisen(II) sulfat-Heptahydrat.

. . , , .


The author gratefully acknowledges the support extended by Professor P. K. Jena, Director of this laboratory, and the permission to publish the results.  相似文献   

7.
Platinum(II) catalyzes the reduction of alkyl iodides to alkanes according to a mechanism involving oxidative addition of RI to Pt(II), reduction of the product complex RPt(IV) to RPt(II) by iodide ions and protolysis of the latter particle.
(II) , RI PtII, - RPtIV RPtII .
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8.
Summary In an attempt to develop potential inhibitors ofUDP-glucuronosyltransferase, some 5-O-amino acid derivatives of uridine were synthesized. N-protectedL-amino acids were coupled at the 5-O-position of 2,3-O-isopropylideneuridine by esterification employing the method of symmetrical anhydrides in presence of 4-dimethylaminopyridine, 5-O-(N-benzyloxycarbonyl-O-tert.butyl-L-threonl)-23-O-isopropylideneuridine (1), 5-O-(N-tert.butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylideneuridine and (2), 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (3), and 5-O-(N-tert.butyloxycarbonyl-L-valyl)-2,3-O-isopropylideneuridine (4) were obtained in good yield after column chromatography on silica gel. The treatment of2 withTFA/CH2Cl2 (6:1) at room temperature for 30 min led to a selective removal of theBoc group without deblocking of the 2,3-O-isopropylidene group of uridine. Treatment of2 withTFA/H2O (5:1) at room temperature for 1 h, however, released bothBoc and 2,3-isopropylidene groups. TheZ group of1 was deprotected by catalytic hydrogenolysis over 10% Pd/C/ammonium formate.
Synthese von 5-O-Aminosäurederivaten des Uridins als potentielle Inhibitoren derUDP-Glukuronosyl-Transferase
Zusammenfassung In einem Versuch, potentielle Inhibitoren derUDP-Glukuronosyl-Transferase zu entwickeln, wurden einige 5-O-Aminosäurederivate des Uridins synthetisiert. N-GeschützteL-Aminosäuren wurden durch Veresterung mit der 5-O-Position des 2,3-isopropylidenuridins gekuppelt (Methode der symmetrischen Anhydride in der Gegenwart von 5-Dimethylaminopyridin). Solcherweise wurden 5-O-(N-Benzyloxycarbonyl-O-tert.butyl-L-threonly)-2,3-O-isopropylidenuridin (1), 5-O-(N-tert.Butyloxycarbonyl-O-benzyl-L-seryl)-2,3-O-isopropylidenuridin (2), 5-O-(N-tert.Butyloxycarbonyl-L-leucyl)-2,3-O-isopropylidenuridin (3) und 5-O-(N-tert.Butyloxycarbonyl-L-valyl)-2,3-O-isopropylidenuridine (4) nach Säulenchromatographie (Kieselgel) in guter Ausbeute hergestellt. Die Behandlung von2 mitTFA/CH2Cl2 (6:1) bei Zimmertemperatur (30 min) führte zu einer selektiven Abspaltung derBoc-Gruppe ohne Deblockierung der 2,3-O-Isopropylidengruppe des Uridins. Eine Behandlung von2 mitTFA/H2O (5:1) bei Zimmertemperatur für 1 Stunde führte hingegen zur Abspaltung sowohl derBoc als auch der 2,3-O-Isopropylidengruppe. DieZ-Gruppe von1 wurde durch katalytische Hydrogenolyse auf 10% Pd/C/Ammoniumformiat abgespalten.
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9.
The viscosities of dilute solutions of a number of tetraalkylammonium and alkali metal halides, tetraphenylarsonium chloride, sodium tetraphenylborate, and tetrabutylammonium tetrabutylborate, as well as several nonelectrolytes have been measured in the high dielectric constant solvent N-methylacetamide (NMA) at 35 and 55°C. The relative viscosities were fitted to the extended Jones-Dole equation, = 1 + AC1/2 + BC + DC2. The pattern of behavior of the B coefficients is roughly similar to that observed in H2O. However, the small ions have exceptionally large B values in this solvent due to strong solvation effects, while the large organic ions do not display the sharp crossing of the Einstein law, B=2.5 V, characteristic in H2O of hydrophobic interaction. The D coefficients roughly parallel the B behavior and display remarkably regular ionic trends. This suggests that they arise largely from hydrodynamic origins. Nonelectrolytes have small or negative B coefficients showing that the Einstein law is not applicable at the molecular level and that nonelectrolytes are poor models for structurally similar ions. A simple mixture law is presented as an alternative to the Einstein law to explain the B coefficients.  相似文献   

10.
    
NO2 ( CCl4, 22°). .
The kinetics and mechanism of cyclohexane oxidation by ozonized oxygen have been studied in the presence of NO2. The proposed mechanism involves the following steps: (1) O3+NO2N3+O2; (2) NO2+N3N2O5, (3) N3+RHR+HNO3, (4) R+O2R2, (5) R2+NO2ROONO2 In CCl4 at 22°C, k2/k3=(1.2±0.4)×104 and k1=(1.0±0.3)x x 105l mol–1s–1.
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11.
TG and DTA of the compounds Mn(phen)2X2 (where X=CN,CNO, NCS and NCSe), Mn(phen) (NCS)2, Mn(NCS)2 and Mn(NCSe)2 (wherephen=1,10 phenanthroline) are reported and discussed. Decomposition schemes are proposed based on TG and DTA results and, where possible, the analysis and properties of intermediates formed during thermal breakdown. The decomposition of thiocyanate and selenocyanate ligands is observed to lead to an apparent slight increase in sample weight. This phenomenon is discussed in relation to buoyancy changes resulting from the release of sulphur or selenium vapours.
Zusammenfassung TG und DTA Untersuchungen der Verbindungen Mn(phen)2X2 (X=CN, CNO, NCS und NCSe), Mn(phen) (NCS)2, Mn(NCS)2 und Mn(NCSe)2 (phen =1.10 Phenantrolin) werden beschrieben. Anhand der TG- und DTA-Ergebnisse werden Zerzetzungsschemata vorgeschlagen und wenn möglich, Analyse und Eigenschaften der im Laufe der thermischen Zersetzung entstandenen Zwischenprodukte angegeben. Es wurde beobachtet, da\ die Zersetzung der Thiocyanat- und Selenocyanatliganden zu einer scheinbaren schwachen Zunahme des Probengewichts führt. Dieses PhÄnomen wird im Zusammenhang mit infolge der Abspaltung von Schwefel- oder SelendÄmpfen auftretenden Änderungen des Auftriebs diskutiert.

Résumé On décrit et discute la TG et l'ATD des composés Mn(phén)2X2 (X=CN, CNO, NCS et NCSe), Mn(phén) (NCS)2, Mn(NCS)2 et Mn(NCSe)2 (oùphén=1,10 phénantroline). On propose des schémas de décomposition à partir des résultats de TG et d'ATD et, si possible, on donne l'analyse et les propriétés des produits intermédiaires formés lors de la décomposition thermique. On a observé que la décomposition des ligands de thiocyanate et de sélénocyanate entraine une faible augmentation apparante du poids du prélèvement. On explique ce phénomène par les variations de poussée résultant du dégagement de vapeurs de soufre ou de sélénium.

()22, () (NCS)2, Mn(NCS)2 Mn(NCSe)2, X=CN, CNO, NCS, NCSe =1.10. , , - , . . - , .


We wish to express our thanks to Professor S. C. Bevan for helpful advice, particularly in connection with the buoyancy effect noted for thiocyanate and selenocyanate complexes.  相似文献   

12.
Methyl 1-aryl-3-aroyl-4,5-dioxo-4,5-dihydro-1H-pyrrole-2-carboxylates react with N-substituted 3-amino-5,5-dimethyl-2-cyclohexenones to give 4-hydroxy-1-aryl-3-aroyl-6,6-dimethyl-1, 2,3,4,5,5,6,7-octahydro-1H,2H-indole-3-spiro-2-pyrrole-2,4,5-triones. The structure of the products was proved by the X-ray diffraction data for the 1-cyclohexyl derivative.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 12, 2004, pp. 1840–1845.Original Russian Text Copyright © 2004 by Bannikova, Maslivets, Aliev.For communication XLVIII, see [1].  相似文献   

13.
Linear (planar) molecules A and B which are identical except for isotopic substitutions at the atomic sites are considered. Stretching (bending, out-of-plane) frequencies k and normal modes k of the isotopically perturbed molecule B are expressed in terms of stretching (bending, out-of-plane) frequencies i and the corresponding normal modes i of the unperturbed molecule A. Complete specification of the unperturbed normal modes is not required. All that is needed are stretching (bending, out-of-plane) amplitudes | i of the normal modes i at those sites that are affected by isotopic substitution. The rule which interlaces frequencies k of molecule A with frequencies i of molecule B is derived. Given two isotopic molecules A and B that differ by a single isotopic substitution at site , the inversion relation is derived. This relation expresses unperturbed stretching (bending, out-of-plane) amplitudes at the site in terms of stretching (bending, out-of-plane) frequencies of molecules A and B . As an example, out-of-plane vibrations of deuterated bromoethene were considered. In the simplest method 12 out-of-plane frequencies of four polydeuterated bromoethenes were calculated from 12 out-of-plane frequencies of bromoethene and three monodeuterated bromoethenes. Standard deviation of thus calculated frequencies from experimental frequencies is =2.74 cm–1. In another method, 15 out-of-plane frequencies of four polydeuterated bromoethenes and selected monodeuterated bromoethene are calculated from 9 out-of-plane frequencies of bromoethene and the remaining two monodeuterated bromoethenes. Depending on which monodeuterated bromoethene is selected (1-, cis- or trans-), standard deviation of thus obtained frequencies from experimental frequencies is 1=2.84 cm–1, c=2.96 cm–1 and t=2.72 cm–1.  相似文献   

14.
The telomerization of butadiene with diethylamine with the formation of the tertiary amine (C2H5)2NC8H13 is catalyzed by Ni, Pd and Pt allyl halide complexes. Triphenylphosphine increases the activity of such catalysts. The rate of telomerization depends strongly on the [PPh3]/[M] ratio (M=Pd and Pt) and increases in the series of metals: Ni3H5PdCl)2 exceeds that of (-C3H5)2 Pd by more than two orders of magnitude.
Ni, Pd Pt (C2H5)2NC8H13. . [PPh3]/[M], M=Pd Pt, : Ni3H5PdCl)2 (-C3H5)2Pd.
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15.
A thermal study (simultaneous TG and DTA measurements) was carried out on the dithiocarbazic ester complexes M[N3CH2R1N2C1(S)SCH3]2, where M=Ni, Pt; R1=C6H5. The following disproportionation reaction occurs in the solid state: II is formed through deprotonation of the CH2 group bound to N3, whereas III is formed through protonation of N3.The influence of inductive and/or steric effects on the mechanism of this reaction is discussed, taking into account the electrochemical and X-ray data on the complexes Pt[NRNC(S)SR']2 with differentR substituents: R=H, Ph, CH2Ph, CH2C5H11, CH(CH3)2, C(CH3)3; R=CH3, CH2Ph.These results accord with the behaviour of the same complexes in solution.
Zusammenfassung Dithiokarbamidsäureesterkomplexe M[N3CH2R1N2C1(S)SCH3]2 mit M=Ni, Pt und R1=C6H5 wurden thermisch untersucht. Im festen Zustand spielt sich folgende Disproportionierungsreaktion ab: II wird durch Deprotonierung der an N3 gebundenen CH2 Gruppe und III durch Protonierung des Atoms N2 gebildet. Unter Zuhilfenahme der elektrochemischen und Röntgendaten der Komplexe Pt[NRNC(S)SR']2 mit verschiedenen Substituenten R: R=H, Ph, CH2Ph, CH2C5H11, CH(CH3)2, C(CH3)3 und R=CH3 bzw. CH2Ph wurde der Einfluß von induktiven und/or sterischen Effekten auf den Reaktionsmechanismus diskutiert. Diese Ergebnisse stehen in Übereinstimmung mit dem Verhalten der Komplexe in Lösung.

M[N3CH2R1N2C1(S)SCH3]2, M= Ni, Pt,R 1=C6H5. : II CH2 , N3, III N2. () , Pt[NRNC(S)SR]2, R= , aR= . .


We thank prof. A. La Ginestra for many helpful discussions on the various aspects of this work.  相似文献   

16.
Résumé Sous azote ou sous vide, le sulfite ferreux anhydre se décompose vers 210° en magnétite, pyrite et dioxyde de soufre. Concurremment une réaction de dismutation intervient avec formation de FeSO4, Fe3O4 et FeS2. Lorsque la température atteint 320°, la pyrite et le sulfate réagissent ensemble pour donner Fe1–xS, Fe3O4 et SO2. Au-delà de 370° le sulfure ferreux non-stchiométrique commence à réagir à son tour avec le sulfate restant pour former de la magnetite et du dioxyde de soufre.
In nitrogen or under vacuum, anhydrous iron(II) sulfite decomposes near 210° to magnetite, pyrite and sulfur dioxide. A parallel disproportionation reaction occurs with formation of FeSO4, Fe3O4 and FeS2. When the temperature reaches 320°, pyrite and sulfate react together to give Fe1–xS, Fe3O4 and SO2. Above 370° the non-stoichiometric ferrous sulfide begins to react with the remaining sulfate to give magnetite and sulfur dioxide.

Zusammenfassung Unter Stickstoff oder im Vakuum zersetzt sich das wasserfreie Eisen(II)-sulfit in der Nähe von 210 °C zu Magnetit, Pyrit und Schwefeldioxid. Parallel hierzu findet eine Disproportionierung unter Bildung von FeSO4, Fe3O4 und FeS2 statt. Wenn die Temperatur 320 °C erreicht, reagieren Pyrit und Sulfat unter Bildung von Fe1–xS, Fe3O4 und SO2 Oberhalb von 370 °C beginnt das nichtstöchiometrische Eisensulfit seinerseits mit dem restlichen Sulfat zu reagieren um Magnetit und Schwefeldioxid zu ergeben.

(II) 210° , . FeSO4, Fe3O4 FeS2. 320°, , Fe1–xS, Fe3O4 SO2. 370° .
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17.
In this paper we calculate the effect of surface OH/OH on the simultaneous adsorption of H2 and O2 on ZnO. A quantitative comparison between H2 and CO oxidation rates shows that the two mechanisms are similar for the same water recovery on ZnO.
OH/OH H2 O2 ZnO. H2 CO , ZnO.
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18.
Summary It was shown that In contrast to the Meerwein-Koelsch reaction, the decomposition of benzenediazonlum fluoborate In esters of ,-unsaturated acids proceeds by a heterolytlc mechanism with the phenyl attacking the -carbon and the carbalkoxyl group of these esters. The reaction with ethyl crotonate gave -methylatropic acid (after hydrolysis) and a small amount of a dibasic acid, C14H16O4 (or C14H14O4). With methyl acrylate it gave atropic acid, phenyl acrylate, and a smaller amount of -methyl--phenylglutaric acid. With methyl methacrylate It formed benzylacrylic acid and the product of further conversions of phenyl methacrylate, namely the keto phenol 2-methyl-5-hydroxyindan-1-one.  相似文献   

19.
Seven complex compounds exhibiting the compositions Ni(en)3Ni(CN)4·H2O (I), Ni(en)3Ni(CN)4 (II),-Ni(en)2Ni(CN)4 (III), Ni(en)Ni(CN)4·2H2O (IV), Ni(en)Ni(CN)4 (V), Ni(en)2Ni(CN)4 · 2.5H2O (VI) and-Ni(en)2Ni(CN)4 (VII) were prepared from the system Ni-en-[Ni(CN)4]2–-H2O. These compounds were examined by the methods of infrared spectroscopy, X-ray powder diffractometry, UV-VIS reflectance spectroscopy, and also by the measurement of magnetic moments. The thermal stability, the stoichiometry of thermal decomposition and the mutual transformations were investigated with a derivatograph. The reactions proceeding according to the following schemes were observed if the system was heated to appropriate temperature: (I)(II)(III)(V)(IV) and (VI)(VII)(III)(V)(IV) Process (VII)(III) represents isomerization. The reversibility of the process (V)(IV) is due to the high hygroscopicity of the anhydrous complex. The changes in structure in the course of the individual processes are discussed.
Zusammenfassung Aus einem System Ni-en-[Ni(CN)4]2–-H2O wurden sieben Komplexe der Formeln Ni(en)3Ni(CN)4·H2O (I), Ni(en)3Ni(CN)4 (II),-Ni(en)2Ni(CN)4 (III), Ni(en)Ni(CN)4·2H2O (IV), Ni(en)Ni(CN)4 (V), Ni(en)2Ni(CN)4 · 2.5H2O (VI) und-Ni(en)2Ni(CN)4 (VII) hergestellt. Diese Verbindungen wurden mittels IR-Spektroskopie, Röntgenpulverdiffraktometrie, UV-Reflexionsspektroskopie und durch Messungen des magnetischen Momentes untersucht. Die Wärmestabilität, die Stöchiometrie des thermischen Zerfalles und die gegenseitigen Umwandlungen wurden mittels eines Derivatographen untersucht. Wird das System auf geeignete Temperaturen erhitzt, kann der Reaktionsverlauf durch folgendes Schema dargestellt werden: (I)(II)(III)(V)(IV) und (VI)(VII)(III)(V)(IV).Der Prozeß (VII)(III) verkörpert eine Isomerisierung. Die Umkehrbarkeit von Prozeß (V)(IV) ist auf die ausgeprägten Hygroskopieeigenschaften des wasserfreien Komplexes zurückzuführen. Es werden die im Ablaufe der einzelnen Prozesse vorgehenden Strukturveränderungen besprochen.

Ni- -[No(N)]2 -2 Ni(en)3Ni(CN)4 · 2 (I), Ni(en)3Ni(CN)4 (II),-Ni(en)2Ni(CN)4 (III), Ni(en)Ni(CN)4-2H2O (IV), Ni(en)Ni(CN)4 (V), Ni(en)2Ni(CN)4 · 2,5H2O (VI) -Ni(en)2Ni(CN)4 (VII). , , - , . , . (I)(II)(III)(V)(IV) (VI)(VII)(III)(V)(IV). (VII)(III) . (V)(IV) . .
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20.
Isotope kinetic equations for reversible bimolecular reactions describe the rearrangement of atoms in activated complexes. It has been established from the model reaction CH4+HCH3+H2 that the isotopic homoexchange of methane via two atomic channels is given by one set of equations with different sets of parameters.
- . CH4+HCH3+H2 , .
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