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1.
The rate constants of deuterium exchange for cyclohexane in CH3COOD/D2O have been measured in the presence of 12 complexes of Pt(II) with various ligands (Cl, H2O, NH3, Br, NO2, py, DMSO, PPh3, etc.). The change in the rate constant is shown to follow the reverse series of the trans-effect of Pt(II) ligands. The rate constant of the interaction of PtCl2Sn (S is H2O, CH3COOH, n=1, 2) with cyclohexane in CH3COOD/D2O (11), k, equals 2.5×108 exp (–18200/RT) 1 mol–1 sec–1 (at 354–385 K). The ratio of rate constants for PtCl2S2, PtCl3S and PtCl 4 2– is 10060.5 at 100°C.
CH3COOD–D2O 12- Pt(II) (Cl, H2O, NH3, Br, NO2, , DMCO, PPh3 .). , Pt(II). PtCl2Sn (S–H2O, CH3COOH, n=1,2) 11 CH3COOD–D2O k=2,5·108 exp(–18200/RT). –1 –1 (354–385°). 100°C PtCl2S2, PtCl3S PtCl 4 2– 10060,5.
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2.
In the study of the Fe1–xCrxMo1·5O6 system by X-ray, IR and Mössbauer methods the formation of solid state substitution solutions has been detected, which possess similar catalytic properties in methanol oxidation.
, , Fe1–xMo1·5O6 , .
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3.
The oxidative decarboxylation sequence (1a 2a 3a 4a 5a) affording -aminobutanoic acid (5a) is adapted to the synthesis of its hydroxy derivative5b. A facile high yield conversion of (2S, 4R)-4-hydroxyproline-methylester-hydrochloride (7) to (R)-GABOB (5b) on a preparative scale is reported with the hydroxypyrrolidone8 as the intermediate.
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4.
Within the prospect of quantifying the geometrical dissimilarity of molecular models on the basis of a thermodynamical formalism, the algebra of stereogenic pairing equilibria is reviewed and applied to molecular geometry: developing Rassat's proposition, an interaction energy of two figures F and F is taken as proportional tod H Emphasis>/2 (F, F), whered H denotes the Hausdorff distance. IfG is a group of rotations in E n the geometrical version of the general equation (E) of the chemical algebra defines a distance extensionD p(F,F) ofd H(F,F), which is independent of the orientations of F and F, and where the coefficientp is interpreted as the reciprocal of a temperature-like parameter:p 1/T. At K (p = ), no formal entropy contributes to the definition of the uniform distanceD . At K (p = 0), the discrimination between homo- and hetero-pairing of figures by the harmonic distance Do is averaged over orientation states. Temperature-dependent chirality measuresc p are derived fromD p, andc is analogous to Mislow's chirality measure. If T and oT are normalized enantiomorphic triangles with coincident centroids inE 2,c p(T) =D p (T, T) is calculated forp = 0 andp = , and discussed for 0 <p < . Finally, the Hausdorff interaction model is putatively related to energy profiles versus dihedral angle inmeso- anddl-molecules.  相似文献   

5.
A new differential thermal analysis method has been developed which allows fast and accurate determinations of phase equilibria in condensed systems between 400 and 1100°. In this method the temperature is increased stepwise, heat effects being determined by analysis of the transient thermoelectric effects after each step. Between steps the temperature is kept constant until equilibrium is attained. The method has been tested in measurements of displacive solid-state transformations and melting points.
Zusammenfassung Eine neue Methode der Differentialthermoanalyse wurde entwickelt, welche rasche und genaue Bestimmungen von Phasengleichgewichten in kondensierten Systemen zwischen 400° und 1100° ermöglicht. Bei dieser Methode wird die Temperatur stufenweise erhöht und die Wärmeeffekte durch Analyse der thermoelektischen Übergangseffekte nach jeder Stufe bestimmt. Zwischen den Stufen wird die Temperatur bis zum Erreichen des Gleichgewichts konstant gehalten. Die Methode wurde bei Messungen von Verschiebungsumsetzungen in festem Zustand und von Schmelzpunkten erprobt.

Résumé Une nouvelle méthode d'analyse thermique différentielle a été mise au point. Elle permet de déterminer de façon rapide et exacte les équilibres de phases dans des systèmes condensés, entre 400 et 1100°. Selon cette méthode, on augmente graduellement la température en déterminant les effets thermiques par analyse des effets thermoélectriques intermédiaires après chaque palier. A chaque palier, on maintient la température constante jusqu'à ce que l'équilibre soit atteint. On a contrôlé la méthode par l'étude de changements de phases displacifs dans l'état solide et par mesure de points de fusion.

, 400° 1100°. , . . .
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6.
Conclusions Reaction of stoichiometric quantities of perfluorocyclohexanone and 98% H2O2 in neutral media quantitatively forms ,-dihydroxydi(perfluorohexyl)peroxide, for which the main crystal and molecular structural parameters were determined by x-ray analysis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 918–923, April, 1989.  相似文献   

7.
Zusammenfassung Aus Halogenboranen und Organohalogenboranen (RBX 2R=C6H5, Cl, Br;X=F, Cl, Br) sowie aus Organoboranen oder Thioboranen entstehen mit Phthalodinitril Triisoindolo-[1,2,3-cd1,2,3-gh1,2,3-kl][2,3a,5,6a,8,9a,9b]-hexaazaboraphenalene von denen die B–Cl- und B–F-Verbindungen näher charakterisiert werden.Dekaboran(14), Diboran(6) oder Boranaddukte von Stickstoffbasen liefern hingegen mit Phthalodinitril metallfreies Phthalocyanin.
Triisoindolo[1,2,3-cd1,2,3-gh1,2,3-kl][2,3a,5,6a,8,9a,9b]-hexa-azaboraphenalene
Triisoindolo[1,2,3-cd1,2,3-gh1,2,3-kl][2,3a,5,6a,8, 9a,9b]-hexaazaboraphenalenes are obtained from the reactions of haloboranes and organohaloboranes (RBX 2R=C6H5, Cl, Br;X=F, Cl, Br) as well as from organoboranes or thioboranes with phthalodinitrile. The B–Cl and B–F compound have been characterized by analyses, i.r.-, u.v.- and mass-spectrometry.Diborane(6), dekaborane(14) and amine-boranes, however, upon reaction with phthalodinitrile lead to high yields of metal free phthalocyanine.


Herrn Prof. Dr.M. Pailer zum 60. Geburtstag gewidmet.  相似文献   

8.
Summary The conditional protonation constants (=0.1) for 2,2:6,2-terpyridine, logK 1=4.93, logK 2=3.69, were determined by thepH-metric method. The compositions of complexes of Ag2+ and Ag+ ions with 2,2:6,2-terpyridine (tp) were studied and equilibria of the complex formation process were described. The values of conditional complex formation constants are as follows: for Ag(tp) 2 + :log01=5.79, log02=9.68, for Ag(tp) 2 2+ :log02=25.31, while the conditional constant of the Ag(tp)NO3 precipitate formation is:K SO=2.45·104. Using coulometric and chronovoltamperometric measurements, the redox systems being formed in the complex solutions of Ag(II) and Ag(I) were determined and described including their formal potentials.
Komplexibildungsgleichgewichte und Redoxpotentiale des Systems Ag(II)/Ag(I) in Gegenwart von 2,2:6,2-Terpyridin in Wasser
Zusammenfassung Mit Hilfe derpH-metrischen Methode wurden die konditionalen Protonationskonstanten (=0.1) von 2,2:6,2-Terpyridin bestimmt: logK 1=4.93, logK 2=3.69. Es wurde auch die Zusammensetzung der Komplexe von Ag(II) und Ag(I) mit 2,2:6,2-Terpyridin(tp) bestimmt sowie die Gleichgewichte der komplexbildung beschrieben. Die Werte der Konditionalkomplexbildungskonstanten sind: für Ag(tp) 2 + :log01=5.79, log02=9.68, für Ag(tp) 2 2+ :log02=25.31 und für das Löslichkeitsprodukt Ag(tp)NO3:K SO –1 =4.08·10–5. Die in Komplexlösungen von Ag(II) und Ag(I) vorliegenden Redoxsysteme wurden mittels cyclischer Voltametrie und Coulometrie untersucht und die Formalpotentialwerte dieser Systeme in Wasser bestimmt.
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9.
N,N-DicyclohexylpiperazineN,N-dioxide octahydrate, C16H46N2O10,M r=426.55, monoclinic, space groupC2/m (No. 12),a=12.961(4),b=11.533(4),c=7.907(1) Å, =98.37(2)o,V=1169.3(6) Å3,Z=2. The structure was solved by the direct method and refined toR=0.045 for 1192 observed MoK reflections. TheN,N-dioxide molecule occupies a site of symmetry 2/m. The piperazine ring takes the chair form with the two N–O bonds oriented axially in atrans configuration. Hydrogen bonding between the water molecules, as well as between theN-oxide groups and water molecules, gives rise to a puckered layer composed of edge-sharing four-membered, five-membered, six-membered, and eight-membered rings. Adjacent layers are cross-linked by theN,N-dicyclohexylpiperazine moieties lying between them, thereby generating a sandwich structure consolidated by covalent and hydrogen bonding. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82062 (8 pages).  相似文献   

10.
Pei  Hongxia  Lu  Sheming  Ke  Yanxiong  Li  Jianmin  Qin  Shoubo  Zhou  Shuxi  Wu  Xintao  Du  Wenxin 《Structural chemistry》2004,15(3):207-210
A new Cu(II)PMIDA compound [Cu(H2PMIDA)(phen)] 3H2O (1) (H4PMIDA = H2O3PCH2N (CH2CO2H)2,phen = 1,10-phenanthroline) has been successfully synthesized and structurally characterized. In complex 1, Cu (II) is six coordinated by chelation in a tetradentate fashion by a PMIDA ligand and by two N atoms of a phen ligand. Every phen–Cu(II)–PMIDA group connects with each other via a hydrogen bond and the edge-to-face -stacking interaction. Complex 1 crystallized in triclinic P-1 with cell dimensions of a = 7.5817(6) Å, b = 10.6980(8) Å, c = 13.1852(10) Å, =82.350(2)°, = 84.151(2)°, =78.4250(2), V= 1035.25(14) Å3, Z = 2, Dc = 1.677 Mg/m3.  相似文献   

11.
Summary From a methanolic extract of the roots ofPrangos ferulacea (L) Lindl., growing in the Nakhichevan ASSR, in addition to the compounds found previously, another six substances (I–VI) have been isolated, of which (I) and (VI) have been identified as, respectively, meransin hydrate monoacetate, found for the first time in nature, and umbelliferone: and in the study of a crystalline mixture obtained from the resin of the roots of the plant under investigation collected in Armenia, two coumarins — (VII) and (VIII) — have been isolated.On the basis of a study of IR, NMR, and mass spectra and chemical properties, the structures of the six new cumarin derivatives (II–V, VII, and VIII) have been established. Compound (II) has the structure of 8-(3-methylbutenyloxy)furo-2,3:7,6-coumarin and has been called feruliden; (III) is 7-hydroxy-8-(3-hydroxy-2-senecioyloxyisopentyl) coumarin and has been called ferudiol; (IV) is 7-hydroxy-8-(3-methoxy-2-senecioyloxyisopentyl) coumarin; (V) is 5-[1-(2,3-dihydroxy-3-methylbutyroyloxy)-1-methylethyl]-4,5-dihydrofuro-2,3:7,6-coumarin and has been called lindiol; (VII) is 8-(2-hydroxy-3-methylbut-3-enyloxy)-7-methoxycoumarin and has been called ferudenol; (VIII) is 7-methoxy-8-(3-methyl-2-oxobut-3-enyl)coumarin and has been called prangone.Leningrad Sanitary-Hygenic Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 568–574, September–October, 1974.  相似文献   

12.
Conclusions The reaction of 1,2-bis(methyldimethoxysilyl)ethane and the corresponding ethylene and acetylene derivatives with bis(2-hydroxyethyl)methylamine gives 1,2-bis(2,6-dimethyl-1,3-dioxa-6-aza-2-silacyclooctyl-2)ethane and the corresponding ethylene and acetylene derivatives. Analogously, 1,2-bis(vinyldimethoxysilyl)acetylene gave 1,2-bis(2-vinyl-6-methyl-1,3-dioxa-6-aza-2-silacyclooctyl-2)acetylene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1420–1421, June, 1988.  相似文献   

13.
Zusammenfassung Es wurden die Verbindungen (Hof)2CeCl6, (Hbip)2CeCl6 sowie Ceof 2Cl3OCH3·CH3OH (of=1,10-Phenanthrolin,bip=,-Bipyridin) isoliert. Die ersten zwei Verbindungen sind isomorph und kubisch, die letzte ist röntgenamorph. Beim Erhitzen tritt in allen drei Fällen mit Abspaltung eines aktiven Chlors verbundene Pyrolyse ein. Es wurden auch die IR-Spektren aufgenommen. Das dritte Präparat stellt einen Cer(IV)-Komplex mit einem N-Liganden dar.
Ce(IV)-complexes with ,'-bipyridine and 1,10-phenanthroline
The following compounds were isolated: (H-of)2CeCl6, (H-bip)2CeCl6, and Ce-of 2Cl3OCH3·CH3OH (of =1.10-phenanthroline,bip =.-bipyridine). The first two are isomorphous and cubic, the latter is X-ray amorphous. On heating all compounds pyrolyze with loss of active chlorine, IR spectra are reported. The third compound mentioned is a Ce(IV)-complex with a N-ligand.


Mit 2 Abbildungen  相似文献   

14.
Zusammenfassung 2-Chinolylfluoron bildet mit Zirkonium einen 14-Komplex, dessen Extinktionskoeffizient bei 539 nm max=165000 ist. Das Bestimmungsverfahren für ZrOCl2 in Speisesalz wird auf dieser Farbreaktion aufgebaut.
Photometric determination of ZrOCl2 in table salt
2-Quinolylfluorone forms a 14-complex with zirconium. Owing to its high extinction coefficient max=165000 at =539 nm the complex can be used for the determination of ZrOCl2 in table salt.
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15.
Summary New chiral cyclopentadienyl-titanium and-zirconium complexes Cp2TiCl2, CpCpTiCl2 and Cp2ZrCl2 (Cp=5 -cyclopentadienyl and Cp=substituted cyclopentadienyl), have been synthesized. The (S,S)-3 complex, which forms red plate crystals, has been studied by x-ray analysis. It belongs to the monoclinic space groupC2, witha 23.963(3),b 6.6470(6),c 12.6618(9) Å, 103.089(7)°, V=1964.4(3) Å3 and Z=4. The structure was relined to an R factor of 0.048 for 868 observed reflections.  相似文献   

16.
Zusammenfassung Bei der Umsetzung des Dinatriumsalzes von 6-Chlor-4-phenyl-3,4-dihydro-1H-2,1,3-benzothiadiazin-2,2-dioxid (1) mit 1,4-Dijodbutan inDMF wurde das erwartete 1,3-Butano-derivat nich erhalten.1 wurde einerseits zu 6-Chlor-4-phenyl-1H-2,1,3-benzothiadiazin-2,2-dioxid (4) dehydriert, andrerseits traten je nach Herstellungsweise des Dinatriumsalzes Methylierungsreaktionen ein bzw. es entstanden 6-Chlor-1-(4-jodbutyl)-4-phenyl-3,4-dihydro-1H-2,1,3-benzothiadiazin-2,2-dioxid (7) und 6,6-Dichlor-4,4-diphenyl-3,3,4,4-tetrahydro-3,3-tetramethylenbis(1H-2,1,3-benzothiadiazin)-2,2,2,2-tetroxid (8).
Reaction of 6-chloro-4-phenyl-3,4-dihydro-1H-2,1,3-benzothiadiazine-2,2-dioxide with 1,4-Diiodobutane. (Cyclic and bicyclic sulfamides III)
On reaction of the disodium salt of 6-chloro-4-phenyl-3,4-dihydro-1H-2,1,3-benzothiadiazine-2,2-dioxide (1) with 1,4-diiodobutane inDMF the expected 1,3-butano derivative was not obtained. On the one hand1 was dehydrogenated to give 6-chloro-4-phenyl-1H-2,1,3-benzothiadiazine-2,2-dioxide (4), on the other hand according to the method of preparation of the disodium salt either methylation reactions occured or 6-chloro-1-(4-iodobutyl)-4-phenyl-3,4-dihydro-1H-2,1,3-benzothiadiazine-2,2-dioxide (7) and 6,6-dichloro-4,4-diphenyl-3,3,4,4-tetrahydro-3,3-tetramethylenebis(1H-2,1,3-benzothiadiazine)-2,2,2,2-tetroxide (8) were formed.


Herrn Prof. Dr.H. Nowotny gewidmet.  相似文献   

17.
Summary 8,9-Diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-one (2), 3-substituted 8,9-diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-ones (3a–c), 3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8(7H)-one (4), 8-chloro-3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazine (5), 8-substituted 3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazines (6a–h) and 7-substituted 3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8(7H)-ones(7a–c) were synthesized from 5-amino-3,4-diphenylthieno[2,3-c]pyridazine-6-carboxamide (1).
Synthese neuer Pyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-und Pyrimido[4,5:4,5]thieno[2,3-c]pyridazin-Derivate
Zusammenfassung Folgende Verbindungen wurden ausgehend von 5-Amino-3,4-diphenylthieno[2,3-c]pyridazin-6-carboxamid (1) synthetisiert: 8,9-Diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-on (2), 3-substituierte 8,9-Diphenylpyridazino[4,3:4,5]thieno[3,2-d]-1,2,3-triazin-4(3H)-one (3a–c), 3,4-Diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8[7H]-on (4), 8-Chlor-3,4-diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin (5), 8-substituierte 3,4-Diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazine (6a–h) und 7-substituierte 3,4-Diphenylpyrimido[4,5:4,5]thieno[2,3-c]pyridazin-8(7H)-one (7a–c).
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18.
The two major fundamental obstacles which so far have prevented theisolation of stable silynes, RSiCR (1), are: (a)the existence of more stable isomers, e.g., RRC=Si: (2) and(b) their extremely facile (exothermic) dimerication. The steric andelectronic effects of various substituents R and R (R = alkoxy,alkyl, aryl and silyl; R = alkyl and aryl groups) on the stability ofRSiCR relative to the isomeric RRC=Si:(E(1-2)), and on the energy of dimerization tothe corresponding 1,3-disilacyclobutadienes (E(D)), werestudied computationally using density functional theory (DFT) and theONIOM method. The goal was to find a combination of substituents thatwill make RSiCR more stable than RRC=Si: and whichwill also prevent its dimerization. For R = R = H,E(1-2)) = 40.7 kcal/mol (i.e., 2 islower in energy than 1), and E(D) = –104.0kcal/mol. 1, R = OH, R = m-Tbt 2,6-bis[bis(silyl)methyl]phenyl, is by 11.1 kcal/mol morestable than the isomeric silylidene 2. However, thedimerization of 1, R = OH, R = m-Tbt remains highlyexothermic (by 101 kcal/mol). 1, R = R = m-Tbt and1, R = (t-Bu)3Si, R = m-Tbt, are by 5.8 and 2.0kcal/mol, respectively, less stable than the corresponding 2.However, the dimerization of 1, R = (t-Bu)3Si, = m-Tbt is exothermic by only 12 kcal/mol. For1, R = (t-Bu)3Si, and R = Tbt 2,6-bis[bis(trimethylsilyl)methyl]phenyl, the corresponding1,3-disilacyclobutadiene dimer 3, dissociates spontaneously.Thus, (t-Bu3Si)SiCTbt is predicted to be kineticallystable towards both, isomerization to (t-Bu3Si)TbtC=Si: anddimerization to 3, making it a viable synthetic target. Thereported energies were calculated atB3LYP/6-31G**//B3LYP/3-21G*; good agreement is found betweenthe DFT and the ONIOM results.  相似文献   

19.
Zusammenfassung -Substituierte -Acylvinylphosphonate3 mitE-Konfiguration [R 2CO-CH=C(R 1)-P(O)(OR)2], werden in guten Ausbeuten durchWittig-Reaktion von Acylphosphonsäureestern1 [R 1CO-P(O)(OR)2,R 1=Alkyl oder Aryl] mit (2-Oxoalkyliden)triphenylphosphoranen2 [R 2CO-CH=PPh 3,R 2=Alkyl, O-Alkyl oder CH2 X (X=Br, OMe, CO2 Et)] erhalten.
A convenient route to -substituted dialkyl (E)-3-oxo-1-alkenylphosphonates
-Substituted dialkyl (E)--acylvinylphosphonates [R 2CO-CH=C(R 1)-P(O)(OR)2,3], are easily obtained in good yields byWittig-reaction of dialkyl acylphosphonates1 [R 1CO-P(O)(OR)2,R 1=alkyl or aryl) with 2-oxoalkylidene triphenylphosphoranes2 [R 2CO-CH=PPh 3,R 2=alkyl, O-alkyl and CH2 X (X=Br, OMe, CO2 Et)].
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20.
The Dinitrone 2,2-diphenyl-3,3-bi-3H-indole-1,1-dioxide acts as a demethylating and dehydrogenating agent. The mechanism of interaction of the dinitrone with donors and acceptors does not involve intermediate charge-transfer complexes probably due to a self association between dinitrone molecules (as supported by X-ray determinations). The crystal structure of the dinitrone was obtained by direct methods;a=9.967 (2),b=19.817 (3),c=10.875 (2) Å, =111.2 (2)°, space group P21/n. The finalR andR w were 0.089 and 0.063 for all measured reflexes.
2,2-Diphenyl-3,3-bi-3H-indol-1,1-dioxid: Molekulare Wechselwirkungen und Kristallstruktur
Zusammenfassung Das Dinitron 2,2-Diphenyl-3,3-bi-3H-indol-1,1-dioxid wirkt als Demethylierungs- und Oxydationsmittel. Die Wechselwirkung des Dinitrons mit Elektronen-Acceptoren und Elektronen-Donatoren geht wegen der Selbstassoziation zwischen den Dinitron-Molekülen ohne die dazwischenliegende Bildung eines Charge-Transfer-Komplexes vor sich; das wird auch von Röntgenstrukturuntersuchungen gestützt. Die Kristallstruktur wurde mit direkten Methoden ermittelt:a=9.967 (2),b=19.817 (3),c=10.875 (2) Å; =111.2 (2)°. P21/n. Die endgültigen WerteR undR w waren 0.089 und 0.063 für alle gemessenen Reflexe.
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