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A method of synthesis of 9-alkyl-8-methyl-8-methoxy-1,3,6-trioxo-2,7-diazaspiro[4.4]nonane-4-carbonitriles consisting in the reaction of 3-amino-8-hydroxy-1,6-dioxo-2,7-diazaspiro[4.4]non-3-ene-4-carbonitriles with methanol in the presence of sulfuric acid was developed.  相似文献   

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Synthetic routes to the title compounds ( 4, 12 ) are described. Chiral derivatives of these, 2,7-bis(phenylcarbamoyl)-2,3,7,8-tetraazaspiro[4.4]nonane ( 7 ) and 3,8-dicarbomethoxy-2,3,7,8-tetraazaspiro[4.4]nona-1,6-diene ( 10 ) were prepared. Synthetic routes to diketo derivatives of other tetraazaspiro[4.4]nonanes were explored. 3,3-Dicarbethoxy-1-pyrazoline ( 24 ) and 3,3-dicarbethoxypyrazolidine ( 25 ) were prepared and their reactions with hydrazine examined. Proton and 13C nuclear magnetic resonance spectra of new compounds, including some 5-substituted 3-hydroxypyrazoles, are discussed in relation to structure.  相似文献   

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Reaction of 3-amino-8-hydroxy-1,6-dioxo-2,7-diazaspiro[4.4]non-3-en-4-carbonitriles with amines in 2-propanol at room temperature provided the corresponding ammonium salts of 3-amino-8-hydroxy-1,6-dioxo-4-cyano-2,7-diazaspiro[4.4]non-3-en-2-ides.  相似文献   

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In an unusual manner benzonitrile 5 and the substituted benzonitriles 1 , 14 reacted with benzylmagnesiumhalides to yield, besides dibenzyl, the amidines 7 , 13 , 15 , substituted on the imide nitrogen by a 1,2-diphenyl-vinyl group. The proposed structures are based on NMR. and mass spectra.  相似文献   

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Zusammenfassung Es wird eine Elektrode zur Spektralanalyse von Nichtleitern entwickelt, die dadurch hergestellt wird, daß die pulvrige Probe mit leitendem Kunststoff zusammengemischt und das Gemisch in eine Form eingefüllt und beim Erwärmen durch chemische Reaktion des Kunststoffes gehärtet und geformt wird. Eine Presse erübrigt sich dabei. Die Eigenschaften des elektrisch leitenden Kunststoffes und die Herstellung der Elektrode werden beschrieben. Sie bewährte sich bei der Analyse von Eu, Sm und Gd im ppm-Bereich als Bestandteil von Silicaten und bei der Bestimmung von Halogenen und Schwefel. Die Spektrenanregung erfolgte im Feußner-Funken.
Summary An electrode for the spectral analysis of non-conductors is described. It is prepared by mixing the powdered sample with conducting plastic, filling the mixture into a mould and heating it, whereby the resin is hardened. Use of a press is not required. Properties of the conducting plastics and preparation of the electrode are described. The electrode was successfully applied to the determination of Eu, Sm and Gd in the ppm-range in silicates and to the determination of halogens and sulphur. A Feussner spark was employed for excitation.
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4,5-Diaroyl-1-aryl-1H-pyrrole-2,3-diones reacted with ethyl 3-amino-3-phenylprop-2-enoate to give ethyl 4-aroyl-1,6-diaryl-3-hydroxy-2-oxo-8-phenyl-1,7-diazaspiro[4.4]nona-3,6,8-triene-9-carboxylates. The crystalline and molecular structures of ethyl 4-benzoyl-3-hydroxy-1-(4-methylphenyl)-2-oxo-6,8-diphenyl-1,7-diazaspiro[4.4]nona-3,6,8-triene-9-carboxylate were determined by X-ray analysis.  相似文献   

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