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1.
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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2.
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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3.
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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4.
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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5.
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   

6.
The GC-MS method was used to identify the addition products of methyldichlorosilane to vinyl acetate. Radiation-induced addition of methyldichlorosilane to vinyl acetate produces 2-methyldichlorosilylethyl ethyl ether. The reaction follows a radical-chain mechanism. The ratio of the rate constants of methyldichlorosilyl radical addition to C=C and C=O to vinyl acetate amounts to 0.4±0.1 (303 K).
- . , - 2- . , C=C C=O 0,4±0,1.
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7.
Selenite was boiled in KCl solutions of different concentrations at the respective boiling temperatures and atmospheric pressure. The products were subjected to X-ray diffraction analysis, qualitative infrared analysis, differential thermal analysis and microscopic examination. The product obtained in 1.0 M KCl solution was the -form of calcium sulphate hemihydrate (-CaSO4·0.5H2O). In more concentrated KCl solution (1.5, 2.0, 2.5, 3.0, 3.5 or 4.0 M), the -form of calcium sulphate hemihydrate (-CaSO4·0.5H2O) was formed, and a reaction took place between KCl and CaSO4, which gave a double salt: potassium pentacalcium sulphate monohydrate (K2SO4·5CaSO4·H2O).This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

8.
CpTiCl2-M-surface complexes (M=Al, Si, Mg, Cp=cyclopentadienyl) supported on Al2O3, SiO2, MgO gels are reduced by Et3Al, C3H5MgBr and BuLi to Ti3+ surface compounds which exhibit ESR signals. The g and g values and asymmetry of these signals depend on the kind of gel and reducing agent.
CpTiCl2-M ( M=Al, Si, Mg Cp=), Al2O3, SiO2 MgO, Et3Al, C3H5MgBr, BuLi (Et=–C2H5 Bu=–C4H9) Ti+3, . g g .
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9.
Convenient methods for the synthesis of chiral 2,3-seco-2-deoxynucleosides were developed. An isopropylidene protective group was used to block the 3,5-hydroxy groups in 2,3-seco-uridine. Conversion of the hydroxymethyl group to a methyl group was accomplished by chlorination with a mixture of CCl4 and Ph3P with subsequent reduction with n-Bu3SnH. 2,3-seco-2-Deoxyuridine was obtained after deacetonation. The (S) enantiomer was similarly synthesized starting from 1-(-D-arabinofuranosyl)uracil. 3-O-tert-Butyldimethylsilyl-5-O-(p-monomethoxytrityl)-2,3-seco-2-deoxyuridine, which has optically active centers at C(1) and C(4), was also synthesized.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 822–826, June, 1988.The authors thank Professor M. Ya. Karpeiskii for his constant interest in this research.  相似文献   

10.
The conditions for the formation of O 2 on VCl4/SiO2 catalysts have been investigated. It is shown that thermal vacuum treatment (TVT) of unhydrolyzed catalysts leads to partial hydrolysis of the surface vanadium complex caused by the silanol groups of the support. The ability of the catalysts to generate O 2 radicals was found to depend on the degree of hydrolysis caused by thermal vacuum treatment.
O 2 VCl4/SiO2. , , . , O 2 , .
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11.
BaSeO3·2·5H2O(I), PbSeO3· 2H2O(II) and CdSeO3·3.5H2O(III) were prepared and analysed. Their hygroscopicity and solubility was investigated. These compounds have high thermal Stability, as shown by their TG and DTA data. IR spectra show multi-dentate coordination of selenite to cations, due to considerable splitting of the asymmetric v3 and v4 bands of SeO 3 2 in the 780-730 cm–1 and 420-325 cm–1 region.Tentative structures have been proposed involving bridging oxygen atoms.
Zusammenfassung BaSeO3-2.5H2O(I), PbSeO3 · 2H2O(II) und CdSeO3· 3.5H2O(III) wurden hergestellt, analysiert sowie deren Hygroskopizität und Löslichkeit untersucht. TG- und DTA-Untersuchungen erweisen die hohe thermische Stabilität dieser Verbindungen. Die IR-Spektren zeigen mehrzählige Koordination von Selenit zu Kationen, was aus einer beträchtlichen Aufspaltung der antisymmetrischenv 3 undv 4 Banden von SeO 3 2 im Bereich 780-730cm–1 bzw. 420-325 cm–1 hervorgeht. Es wurden versuchsweise Strukturen mit überbrückenden Sauerstoffatomen vorgeschlagen.

BaSeO3· 2,5H2O, PbSeO3 · 2H2O CdSeO3 · 3,5H2O . . - , v 3 v 4 SeO 3 2 }- 780-730 420-325 –1. , .
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12.
Differential thermal and phase X-ray analyses have shown that MoO3 and Fe2V4O13 form a solid substitution solution, in which Mo6+ ions are incorporate into the crystal lattice of Fe2V4O13 in place of V5+ ions. The solubility limit of MoO3 in Fe2V4O13 at ambient temperature is 18 mole % of MoO3. The phase equilibria in the system Fe2V4O13-FeVMoO7, were also studied. Results are presented in the form of a phase diagram.
Zusammenfassung Durch DTA und Röntgenphasenanalyse wurde gezeigt, daß MoO3 und Fe2V4O13 Substitutionsmischkristalle bilden, in denen Mo6+-Ionen anstelle von V5+-Ionen in das Kristallgitter von Fe2V4O13 eingebaut sind. Die Löslichkeitsgrenze von MoO3 in Fe2V4O13 beträgt bei Umgebungstemperatur 18 Mol-% MoO3. Ebenfalls wurden die Phasengleichgewichte im System Fe2V4O13-FeVMoO7 untersucht. Die Ergebnisse sind in Form eines Phasendiagramms dargestellt.

- , 3 Fe2V4O13 , o6+ V5– Fe2V4O13. 3 Fe2V4O13 18 %. Fe2V4O13-FeVMoO7 .
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13.
The reaction of fluorosilanes with lithium salts of bulky amines like tetramethyl-piperidine and di-tert. butylamine leads to stable aminofluorosilanes of the type R-SiF2-NRR [R=F, C(CH3)3, C6H5, C6H4N(CH3)2]. Lithium salts of silylamines react analogously: R2Si(NR-SiF2R)2 (R=R= =CH3, R=C6H5). An eight membered Si–N-ring is obtained in the reaction of a disubstituted silylaminofluorosilane with the dilithium salt of a silylamine. The mass-,1H-, and19F-NMR spectra of the above mentioned compounds are reported.  相似文献   

14.
By the method of molecular deposition, ions of CrO 2 2+ VO3+ and MoO 2 2+ were supported on a matrix of amorphous SiO2. Different types of organic ligands were supported subsequently on the surface compounds so formed. The catalytic activity of the samples was studied in the decomposition of comene hydroperoxide.
SiO2 CrO 2 2+ , VO3+, MoO 2 2+ . . .
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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.
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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17.
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   

18.
In aqueous solution, PM12–nVnO40 –(3+n) (M=Mo,W) hetero-polyanions provide a much faster oxidation of NO than mononuclear VO 2 + ions, yielding HNO2, NO 3 and reduced HPA.
, PM12–nVnO40 –(3+n) (M=Mo,W) , VO 2 + , NO HNO2 NO 3 .
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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.
    
, [(-C5H8OCH3)PdCl·OCH3] [(-C5H8OCH3)Pd(OCH3)2], (-) .
The two methanolato species [(-C5H8OCH3)PdCl(OCH3)] and [(-C5H8OCH3Pd(OCH3)2] are found to be reactive in reductive decomposition.
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