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1.
The chemical behavior of 1-adamantylnitrenium ion seems to be not known much compared to 1-adamantylcarbinyl cation,2 though one example of the rearrangement of 1-adamantylnitrenium ion to 4-azahomoacamantyl ion has been reported recently by Kovacic et al in the reaction of 1-M,N-dichloroaminoadamantane with aluminum chloride.3 From our interest in the reactivity and rearrangement aptitude of 1-adamantylnitrenium ion, we investigated the reactions of various N-substituted N-chloro-1-adamantylamine derivatives with aluminum chloride. This communication deals with the preliminary results which indicated that the reactions of 1-adamantylnitrenium ion are much affected by the N-substituents and also by the solvents used.  相似文献   

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The preparation and properties of a series of alkoxydialkylaminophenylboranes are reported and their 1H and 13C NMR spectra discussed. The spectra indicate that there is restricted rotation about the boronnitrogen bond in each compound studied.  相似文献   

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Summary The spectrophotometric determination of traces of platinum with 2-pyridyl-2-thienyl-Z-ketoxime is described. Experimental parameters were evaluated and a study of diverse ion tolerance was carried out. Sensitivity was increased by the use of 4-cm cells. Beer's law was obeyed and the molar absorptivity at 473 nm was 7.11×103.
Zusammenfassung Die spektrophotometrische Bestimmung von Spuren Platin mit 2-Pyridyl-2-thienyl-Z-ketoxim wurde beschrieben. Die experimentellen Parameter wurden bewertet und die Toleranz gegen verschiedene Fremdionen ermittelt. Durch Verwendung von 4-cm-Küvetten wurde die Grenze der Bestimmbarkeit herabgesetzt. Das Beersche Gesetz ist gültig; die molare Extinktion beträgt 7,11·103.
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Summary A procedure for the separation of magnesium in the final (soluble) Group of the systematic qualitative semimicro inorganic analysis scheme is described which uses a solvent extraction technique with 8-hydroxy-quinoline in chloroform. Magnesium is detected in the ignition residue of the extract by means of the Titan yellow test. The method has several advantages over other means for the separation of magnesium in qualitative analysis.
Zusammenfassung Ein Verfahren für die Abtrennung des Magnesiums von der letzten Gruppe des systematischen anorganischen Halbmikroanalysenganges wird beschrieben. Es beruht auf der Extraktion des Magnesiums mit chloroformischer 8-Hydroxy-chinolinlösung. Der Extraktrückstand wird verglüht und das Magnesium mit Titangelb nachgewiesen. Die Methode hat gegenüber anderen Möglichkeiten zur Abtrennung des Magnesiums in der qualitativen Analyse verschiedene Vorteile.

Résumé On décrit un procédé de séparation du magnésium dans le groupe final (soluble) du schéma d'analyse minérale qualitative systématique à l'échelle semimicro, utilisant une technique d'extraction par solvant avec l'hydroxy-8 quinoléine dans le chloroforme. On recherche le magnésium dans le résidu de combustion de l'extrait en effectuant l'essai au jaune titane. La méthode présente plusieurs avantages sur les autres procédés de séparation du magnésium en analyse qualitative.


Part XVIII. Mikrochim. Acta [Wien]1961, 88.

Dedicated to Prof.A. A. Benedetti-Pichler on the occasion of his 70th birthday.  相似文献   

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Thermal stability of samples of polychloral prepared with different initiators and treated with various endcapping agents was studied using differential thermogravimetric analysis (DTG). Four temperature regions at which maxima of DTG curves occur were identified. On the basis of the known mechanism of initiation and the possible mechanism of termination, the structures of both initial and terminal endgroups of individual polychloral samples were elucidated which enabled the identification of the specific temperature region of thermal degradation of polychloral molecules having a specific type of endgroup. These results were confirmed by studies of the DTG curves of chloral-isocyanate copolymers containing stable terminal fragments with a high content of urethane linkages.  相似文献   

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A series of linear trifluoropropyl-substituted polycarboranylenesiloxanes with molecular weights between 3,500 and 13,000 has been prepared by the tetramethylguanidine–sulfuric acid-catalyzed condensation of various silanol-terminated monomers as well as by simple hydrolytic condensation of m-B10H10C2(SiMePfOSiMePfCl)2 and B5H5C2-(SiMePfCl)2 (where Pf = ? CH2CH2CF3). The polymers containing the C2B5H7 and C2B10H12 carboranes range from hard glasses to viscous gums and rubbers, are more thermally stable than fluorinated silicones with comparable resistance to solvents, and are potentially useful as high-temperature fuel tank sealants.  相似文献   

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The effect of bulky N-substitutents of N-t-butyl- and N-phenyl-N-allylmethacrylamides (BAMA and PAMA, respectively) on their cyclopolymerizability was investigated. BAMA yielded an almost completely cyclized polymer while the degree of cyclization of poly (PAMA) was about 95%. The latter value indicates that the effect of phenyl group is comparable with that of methyl group, since N-methyl-N-allylmethacrylamide was reported to give a polymer with a degree of cyclization of 93%. Structural investigation on telomerization products of BAMA and PAMA permitted the assignment of the repeating cyclic units of these polymers to that of a five-membered ring. This structural characteristic was also supported by the observation of five-membered cyclized radicals on ESR measurements of these monomers. Rotation around amide C? N bonds of these monomers and related compounds studied by 13C-NMR was found to be strongly dependent on N-substitutents. The mechanism of the cyclization was discussed in terms of the structure of the ring formed and rotation around amide C? N bonds of these monomers. The reactivity of the methacryloyl and allyl groups involved in these monomers were compared based on the information obtained by structural investigation of polymers and telomerization products and by ESR studies. © 1993 John Wiley & Sons, Inc.  相似文献   

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Particle–hole and pairing relationships are obtained within the framework of the unitary group formulation of the many-electron problem using the concept of particle–hole conjugation. Besides the familiar relationships for alternant hydrocarbons, relationships among various pericyclic reaction paths are obtained.  相似文献   

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Summary Reaction between K2[ReI6] and KSCN in boiling MeOH or in the melt gave [Re(NCS)6]2– and a weakly paramagnetic species, isolated as its Cs salt. Tl, Me4N and other salts of this species have been isolated from the reaction medium of from the Cs salt by metathesis. On the basis of magnetic susceptibility and i.r. spectra the new complex has been formulated as [Re2(NCS)12]4– containing metalmetal bond and no bridging thiocyanate. The Me4N salt has also been isolated by bioling aqueous solutions of HReO4 and HSCN and then adding Me4NCL. A pyridinium salt, formulated as (pyH)4[Re2(NCS)12], has been obtained by boiling [ReO2py4]NCS with aqueous HSCN. The two complex species [Re(NCS)6]2– and [Re2(NCS)12]4– show distinctly different magnetic moment and electronic spectra.  相似文献   

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2-Mercaptobenzothiazolyl methacrylate (MBTM) was synthesized by the reaction of 2-mercaptobenzothiazole and methacrylyl chloride in tetrahydrofuran at -18°C. MBTM was found to polymerize in the presence of 2,2′-azobisisobutyronitrile (AIBN), n-BuLi, and UV light. From the kinetic studies of radical polymerization of MBTM with AIBN in benzene at 60°C, the overall activation energy was determined to be 18.9 kcal/mole, and the rate of polymerization (R) was expressed as Rp = k[AIBN]0.5 [MBTM], where k is the overall polymerization rate constant. From these results this polymerization was confirmed to proceed via an ordinary radical mechanism. This monomer (M2) was also copolymerized radically with styrene (M1) at 60°C, and the resulting copolymerization parameters were determined as r1 = 0.042, r2 = 0.20, Q2 = 4.09, and e2 = 1.39. The thermal stability and the photodegradation behavior of the polymers were examined, and they were compared with those of the related polymers.  相似文献   

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Reduction in alcohol solution, using hydrogen at atmospheric pressure and platinum oxide catalyst, of 3, 3, -6, 6-tetramethyl-1, 2, 3, 4, 5, 6, 7, 8-octahydroacridine-1, 8-dione and its 9-phenyl derivative gives the corresponding 3, 3, 6, 6-tetramethyl-1, 2, 3, 4, 5, 6, 7, 8, 9, 10-decahydroacridine-1, 8-dione and its 9-phenyl derivative.For part XVIII see [1].  相似文献   

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