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A series of β-ketoselenenic acids was generated at low temperature ( - 20° to - 50°) by selenoxide syn elimination of appropriate selenoxides (13-ox, 16-ox, 35-ox, 38-ox, and 39-ox). No evidence for the buildup of significant concentrations of selenenic acid was obtained. A selenolseleninate (15, 2,2' - diseleno - bis(1 - phenyl - 2 - methyl -1 - propanone) - Se - oxide) was detected as an intermediate in the decomposition of 13-ox and 16-ox. This compound, which is stable in solution below - 50° was charaeterized by NMR spectroscopy (1H, 13C,77Se) and by its thermal decomposition and reactions with phosphite (reduction to diselenide 6) and dialkylamines (formation of selenenamide 11). Decomposition of 15 in the presence of dibenzylamine resulted in trapping of a selenenic acid-like species (RSeSeOH) to give RSeSeN(CH2Ph)2 (R = PhC(O)C(CH3)2). Although 15 could not be prepared by oxidation of diselenide 6, it was possible to prepare a cyclic selenolseleninate (4,4-dimethyl-1,2-diselenolane monoxide, 20) by oxidation of the related diselenide (19). Attempts to prepare more stable aliphatic selenenic acids by blocking the principal decomposition pathway of 15 were not successful. Thus 1 - benzoyl -1 - cyclopropaneselenenic acid was generated from 35-ox and 38-ox and 1 - benzoyl - 2,2 - dimethylcyclopropaneselenenic from 39-ox. The former underwent normal disproportionation (to 36 and 37) even when prepared at -49°. The latter gave what appeared to be a selenolseleninate (40) which again disproportionated at -17°.  相似文献   

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Ohne ZusammenfassungPalmnicken, Ost-Preussen.  相似文献   

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Zusammenfassung Komplexverbindungen, bestehend aus substituierten 2-Methylthiomethylanilinderivaten und Metallhalogeniden (CuCl2, CoCl2, NiCl2) wurden hergestellt.Verbindungen mit der stöchiometrischen Zusammensetzung:MCl2 An 2 (M=Co, Ni;An=o-Methylthiomethylanilin) waren spin normal (high spin, spin free), und die Größe der magnetischen Momente sowie die diffusen Reflexionsspektren der Verbindungen führten zu der Annahme, daß im festen Zustand oktaedrische Koordination vorliegt. In Lösung waren dagegen die Verbindungen meist unbeständig. Es konnte für Co(II) in Lösung (DMF, Nitromethan) tetraedrische Koordination eindeutig nachgewiesen werden.Aus den magnetischen und spektralen Daten der Cu(II)-Komplexe CuCl2 An konnte leider die sterische Konfiguration nicht eindeutig festgelegt werden; in Analogie zu anderen Cu-Anilin-Komplexen ist tetragonale Struktur am wahrscheinlichsten. Die sterischen und induktiven Effekte, die verschiedene Kernsubstituenten auf die Donoreigenschaften des Methylthiomethylanilins und damit auch auf die Eigenschaften des Metallkomplexes ausüben, waren vernachlässigbar, so daß die wesentlichen Eigenschaften der Komplexe praktisch nur von der Art des Metalls, nicht aber vom verwendeten Anilinderivat abhängig waren.
Metal complexes of some o-methylthiomethyl-anilines
Complex compounds of some differently substituted 2-methylthiomethylaniline derivatives and metal halides like CuCl2, CoCl2 or NiCl2, were prepared.Compounds with the stoichiometric compositionMCl2 An 2 (M=Co, Ni;An=2-methylthiomethyl-aniline) were spin normal (high spin, spin free) and their magnetic moments and solid diffuse reflectance spectra indicated the existence of octahedral coordination in the solid state. In solution the complexes were not stable. Clear evidence could be found for the occurrence of tetrahedral coordination of Co(II) inDMF or nitromethane.Alas, the magnetic and spectral data obtained for copper-complexes CuCl2 An were not sufficient to establish definitely their steric configuration. In analogy to other Cu(II)-aniline-complexes tetragonal structure seemed to be the most probable one. The essential properties of the complex compounds were not depending on the aniline derivatives used but only on the metal, so that steric and inductive effects of ring substituents, which could have caused a pronounced alteration of the donor properties of the methylthiomethylaniline derivatives and also of the properties of the metal complexes, could be neglected.
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Imidazo[1.2-b]-,s-Triazolo[4.3-b]- ands-Triazolo-[2.3-b]pyridazines and their derivatives were submitted to homolytic phenylation and the reaction mixtures obtained separated by chromatography into individual components which were then identified. Homolytic phenylation takes place preferentially at position 8 of all systems investigated, whereas a lower selectivity was observed for positions 7 and 3.  相似文献   

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Zusammenfassung An Hand der Pulverdiagramme wurden die Gitterkonstanten von Ca5(VO4)3Br, Sr5(VO4)3Br und Ba5(VO4)3Br ermittelt. Alle drei Verbindungen kristallisieren hexagonal und besitzen die Apatitstruktur. Mit den erhaltenen Daten werden einige kristallchemische Betrachtungen sowie Vergleiche mit anderen verwandten Verbindungen gemacht.
Crystallographic data of some vanadium bromoapatites
The unit cell parameters of Ca5(VO4)3Br, Sr5(VO4)3Br and Ba5(VO4)3Br, calculated by means of powder diagramms, are given. The compounds belong to the hexagonal system and crystallize with the apatite structure. With the obtained data, some comparisons are made and some aspects of the crystal chemistry of these and related compounds are discussed.


7. Mitt. der Reihe Orthovanadate und verwandte Verbindungen; 6. Mitt.:E. J. Baran undP. J. Aymonino, Z. anorg. allgem. Chem.390, 77 (1972).  相似文献   

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Zusammenfassung Mit Hilfe von Gemischen wurden die formalen Redoxpotentials einiger einfacher Aminophenoxazone-(3) und 2-substituierter Gallocyaninmethylesterderivate (Prune) mit den Substituenten — NH-C6H4X [X = H, CH3, OCH3, OH, NH2, N(C2H5)2] in 50%iger Äthanollösung mit einer konstanten Ionenstärke in der Abhängigkeit vom pu bei 25° C gemessen.Die auf pH=0 extrapolierten Potentiale stehen mit den Hammetschen -Konstanten in guter Korrelation.
Summary With the aid of mixtures the formal redox potentials of several simple aminophenoxazones-(3) and 2-substituted gallocyaninmethylester derivates (Prunes) with the substituents -NH-C6H4X [X = H, CH3, OCH3, OH, NH2, N(C2H5)2] were measured in 50% ethanol solution with a constant ionic strength with respect to the dependence of pn at 25° C. The potentials extrapolated to pn = 0 are in good correlation with the Hammet -constants.


Wir danken Herrn Ing.Z. Stránský C. Sc. für wertvolle Erinnerungen bei der Interpretation der Ergebnisse.  相似文献   

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