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21.
Zusammenfassung Der Lösungsmitteleinfluß bei der Alkylierung von 4-Hydroxy-carbostyrilen (1–3) mit Äthyl- bzw. Methyljodid und Allylbromid wird untersucht. Während inDMF und Äthanol fast ausschließlich O-Alkylierung zu den 4-Alkoxy-carbostyrilen (4–7) eintritt, beobachtet man in wäßr. Alkalien auch die Bildung von C,C-dialkylierten Verbindungen (8–10). 3-Äthyl-4-hydroxy-carbostyril (2) reagiert leichter mit C2H5J zum 3,3-Diäthyl-2,4-dioxo-tetrahydrochinolin (8) als das unsubstit. 4-Hydroxy-carbostyril (1). Einige in der Literatur als 3,3-disubstit. 2,4-Dioxo-tetrahydrochinoline formulierte Verbindungen werden als Carbostyril-4-äther erkannt.
The influence of the solvent in the alkylation reaction of 4-hydroxyquinol-2-ones (1–3) with various alkyl halogenides has been studied.DMF and ethanol favor high yields of O-alkylated products (4–7), in aqueous alkali, however, carbon alkylation successfully competes with O-alkylation, affording a substantial amount of 3.3-disubstituted 2.4-dioxo-tetrahydro-quinolines (8–10). The reexamination of a patent showed that some compounds previously described as 2.4-dioxo-tetrahydro-quinolines actually are carbostyril-4-ethers.相似文献
22.
Thérèse Dupuis 《Mikrochimica acta》1967,55(3):452-460
Résumé Par chauffage à 1000° de mélanges d'oxyde stannique et d'oxyde de cadmium en proportions diverses, comme par déshydratation de précipités mixtes des hydroxydes correspondants, il se forme une série de solutions solides de l'oxyde de cadmium dans l'oxyde d'étain. Elles sont solubles dans l'acide chlorhydrique et présentent un spectre d'absorption infrarouge caractéristique que l'on a comparé avec celui des 2 métastannates de cadmium CdSnO3, l'un de type ilménite, l'autre de type perovskite.
Summary By heating various mixture of stannic oxide and cadmium oxide to 1000° C, a series of solid solutions of cadmium oxide in stannic oxide results as is the case when mixed precipitates of the corresponding hydroxides are dehydrated. They are soluble in hydrochloric acid and yield a characteristic infrared absorption spectrum that was compared with that of the two cadmium métastannates CdSnO3, one of the ilmenite type, the other of the perovskite type.
Zusammenfassung Erhitzt man verschieden zusammengesetzte Gemische von Zinnoxid und Cadmiumoxid auf 1000° C oder werden Mischfällungen der entsprechenden Hydroxide dehydratisiert, so entsteht eine Reihe fester Lösungen von Cadmiumoxid in Zinnoxid. Sie sind in Salzsäure löslich und zeigen ein charakteristisches Absorptionsspektrum im IR. Dieses wurde mit dem Spektrum zweier Cadmium-Metastannate (CdSnO3) vom Typus des Ilmenits bzw. Perovskits verglichen.相似文献
23.
Zusammenfassung Bei der Reaktion vonSchiffschen Basen mit Cyanacetylchlorid entstehen über labile Addukte -Cyanzimtsäure-anilide, die in Gegenwart von AlCl3 zu Derivaten des 3-Cyan-4-phenyl-3,4-dihydrocarbostyrils reagieren. Aus diesen kann durch Verseifung die Cyangruppe eliminiert werden.
Herrn KollegenO. Hromatka, Wien, mit den besten Wünschen zum 60. Geburtstag. 相似文献
The reaction of azomethines with cyanoacetyl chloride leads via instable adducts to -cyanocinnamic anilides, which with AlCl3 undergo cyclisation to derivatives of 3-cyano-4-phenyl-3,4-dihydrocarbostyrils. The cyano group in these compounds can be removed by hydrolysis and decarboxylation.
Herrn KollegenO. Hromatka, Wien, mit den besten Wünschen zum 60. Geburtstag. 相似文献
24.
G. J. De Jong U. A. Th. Brinkman W. Th. Kok 《Journal of Radioanalytical and Nuclear Chemistry》1977,35(2):245-252
An investigation has been made on the system liquid anion-exchanger-Cd(II)-NCS−. The influence of the acidity and thiocyanate concentration of the aqueous phase on the extraction has been studied. Using
various methods of analysis, it has been shown that the complex anion present in the organic extracts is Cd(NCS)
4
2−
. Details are given concerning the removal of traces of Zn(II) from Cd(II)-containing solutions, and the quantitative separation
of Cd(II) from Cr(III). 相似文献
25.
Fluorocarbons containing higher halogens have the potency of breaking certain hydrogen bonds in solutions. The relative strength of this potency varies in the series F < Cl < Br < I and the presence of hydrogen atoms in the fluorocarbon increases it. There is a striking parallelism between the hydrogen bond breaking and the anaesthetic potency of these molecules. It is suggested that the breaking of hydrogen bonds is an important step in the mechanism of anaesthesia. 相似文献
26.
Thérèse Dupuis 《Mikrochimica acta》1967,55(3):461-464
Résumé Dans le spectre d'absorption infrarouge de l'iodatochromate de potassium K[(CrO3)(IO3)], on peut identifier la présence de bandes de vibration de valence de ponts Cr-0-I à 508 et680 cm–1.
Summary The infrared absorption spectrum of potassium iodatochromate K(CrO3)(IO3) contains vibration bands of the valence bridges Cr-O-I at 508 and 680 cm–1.
Zusammenfassung Im Infrarot-Absorptionsspektrum des Kaliumjodatochromats lassen sich Banden der Valenzschwingungen der Atomgruppe Or-O-J bei 508 und 680 cm–1 nachweisen.相似文献
27.
Summary The use of non-segmented flow, post-column reaction detection is evaluated for use with miniaturized HPLC. Non-segmented open-tubular reactors with internal diameters 0.1 mm to 0.25 mm and packed-bed reactors with internal diameters of 1 mm, filled with 5 and 10 m particles are evaluated theoretically and experimentally with respect to band broadening and pressure drop characteristics. An integrated system consisting of miniaturized HPLC (1 mm i. d.) columns and compatible hardware is described. An example of the separation of catecholamines is given. 相似文献
28.
Summary A technique is presented for the extraction of free and conjugated drugs and related compounds out of small quantities of urine. The method is designed in such a way that many samples can be tested for a great number of substances at the same time. Furthermore, we tried to achieve a high quality analysis using when ever possible chemicals with relatively low toxicity to men and environment. Therefore we avoided e.g., halogenated hydrocarbons. The detection of the substances is only performed by thin-layer chromatography (TLC) using well known reagents, like ninhydrin, Dragendorff, iodoplatinate and ferric chloride solutions. If necessary, the extracts can also be used with other Chromatographic techniques, particularly with GC/MS, if a substance has to be clearly identified. Approximately 500 authentical urines have been analyzed in a 1 year period using the method described. We found about 75 different substances. These results are presented in a table. 相似文献
29.
J.W. Hofstraat M. Engelsma R.J. Van De Nesse C. Gooijer N.H. Velthorst U.A.Th. Brinkman 《Analytica chimica acta》1986
The coupling of liquid chromatography (l.c.) on narrow-bore columns to thin-layer chromatography (t.l.c.) is described. The effluent from a l.c. column can be deposited on a t.l.c. plate after a normal-phase or reversed-phase separation without serious loss of chromatographic information. Both silica and alkyl-modified silica plates can be used for storage. The interface is a fused silica capillary which connects the column outlet to the spray jet assembly of a Linomat applicator for t.l.c. The stored chromatogram can serve as starting point for a new separation, but also allows the use of detection principles which are normally not compatible with l.c. The chromatography of some polynuclear aromatic hydrocarbons is used to illustrate the possibilities of the combinations. 相似文献
30.
Growth of Single Crystals of Ternary Rare Earth Vanadium(III) Oxides LnVO3 by Flux Electrolysis A simple method for growing single crystals of rare earth vanadium(III) oxides LnVO3 (Ln = La, Sm, Gd, Dy, Er, Yb) by cathodic reduction, starting from vanadium(V) oxide, in a flux of sodium tetraborate and sodium fluoride at T = 1000 K is described. The products were obtained as black, prismatic crystals, suitable for X-ray investigations etc. They were characterized by electron microprobe analyses and by X-ray powder investigations. 相似文献