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  • 1
    Electronic Resource
    Electronic Resource
    Bestimmung von 3-Hydroxy-6-methyl-pyridin in Zucker-Couleur durch Gaschromatographie (1987)
    Springer
    European food research and technology 184 (1987), S. 187-188 
    Details
    ISSN: 1438-2385
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Description / Table of Contents: Zusammenfassung Neben dem bekannten 4-Methylimidazol wird 3-Hydroxy-6-methyl-pyridin als weitere Leitsubstanz für Zuckercouleurs beschrieben. Nach Extraktion mit Diethylether und Überführung in ein Trimethylsilyl-Derivat erfolgt der gaschromatographische Nachweis mittels Flammenionisationsdetektor und Massenspektrometrie. Die Trennung erfolgt an einer fused-silica-Capillare, belegt mit SE 30. Als innerer Standard wird 3-Dimethylamino-phenol verwendet. 5 weitere Substanzen im Extrakt können über ihr Massenspektrum charakterisiert werden.
    Notes: Summary In addition to the well known 4-methyl-imidazole, 3-hydroxy-6-methyl-pyridine may be used as another indicator compound for caramels. After extraction with diethylether and derivatization with BSTFA the quantitative determination is performed by gas chromatography (flame ionisation and mass spectrometry as detectors). 3-Dimethylamino-phenol is used as internal standard. Five other compounds extracted from caramels are characterized by its mass spectra.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01042204
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  • 2
    Electronic Resource
    Electronic Resource
    An improved and facile synthesis of 2-amino-1,1,3-tricyanopropene (1985)
    Springer
    Monatshefte für Chemie 116 (1985), S. 689-691 
    Details
    ISSN: 1434-4475
    Keywords: Malononitrile ; Dimerization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Eine einfache Dimerisierung von Malononitril unter Verwendung von Alkalihydroxid in Methanol und Ethanol wird beschrieben. Dabei entsteht in guter Ausbeute 2-Amino-1,1,3-tricyan-propen, ein wichtiges Ausgangsprodukt zur Synthese von Heterocyclen.
    Notes: Abstract A simple method for the dimerization of malononitrile using alkali hydroxides in methanol or ethanol is described. Thereby 2-Amino-1,1,3-tricyanopropene, a keyintermediate for heterocyclic chemistry, is obtained in high yield.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00798796
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  • 3
    Electronic Resource
    Electronic Resource
    Ozonolysis of olefins, V: Emulsion ozonization of methyl linoleate and methyl linolenate in aqueous alkaline hydrogen peroxide (1991)
    Springer
    Monatshefte für Chemie 122 (1991), S. 719-724 
    Details
    ISSN: 1434-4475
    Keywords: Ozonization ; Fatty esters ; 8-Hydroxyoctanoic acid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Die Ozonolyse von Linol- und Linolensäuremethylester wurde in neutraler bzw. alkalischer wäßriger Emulsion von Wasserstoffperoxid untersucht. Dabei wurden im Reaktionsgemisch mittels GC/MS neben Malonsäuredimethylester (3b), Azelainsäuredimethylester (3h) und Hexansäuremethylester (2a) weitere homologe Dicarbonsäuren (3a–g), Oxocarbonsäuren (4a, b, e–h) und Hydroxycarbonsäuren (4c, d) nachgewiesen. Weiters wurde eine Methode ausgearbeitet, mit der es gelang, 8-Hydroxyoctansäure (4d) — eine hinsichtlich ihrer biologischen Aktivität bedeutende Verbindung — durch Methylierung und Extraktion aus dem Reaktionsgemisch abzutrennen.
    Notes: Summary The ozonolysis of methyl linoleate and methyl linolenate in neutral and alkaline aqueous emulsions of hydrogen peroxide was investigated. Besides the expected products such as dimethyl malonate (3b), dimethyl azelate (3h) and methyl hexanoate (2a) further homologous methyl esters of dicarboxylic acids (3a–g), oxo carboxylic acids (4a, b, e–h) and hydroxy carboxylic acids (4c, d) could be detected by GC/MS analysis. Furthermore a method for separation of 8-hydroxyoctanoic acid (4d) by methylation and extraction of the reaction mixture containing the ozonolysis products is described.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00811471
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  • 4
    Electronic Resource
    Electronic Resource
    Ricinin — einfach synthetisiert (1984)
    Springer
    Monatshefte für Chemie 115 (1984), S. 1467-1470 
    Details
    ISSN: 1434-4475
    Keywords: 4-Methoxy-1-methyl-2(1H)-pyridone-3-carbonitrile ; Alkaloid synthesis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Cyclization of 1,1-dicyano-4-(N,N-dimethylamino)-2-methoxy-1,3-butadiene leads to 4-methoxy-2(1H)-pyridone-3-carbonitrile and 2,4-dimethoxy-pyridine-3-carbonitrile. Methylation of both products yields ricinine.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00816346
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  • 5
    Electronic Resource
    Electronic Resource
    Cyclisierung von Oligomeren des Malodinitrils mit Amidinen Synthesen mit Nitrilen, 55. Mitt (1979)
    Springer
    Monatshefte für Chemie 110 (1979), S. 1279-1285 
    Details
    ISSN: 1434-4475
    Keywords: Aminopyridines ; Malononitriles ; Pyrimidines
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Condensation of formamidine-acetate with dimeric malononitrile (1 a) leads to 2,4-diamino-3,5-pyridine-dicarbonitrile (3 a), with acetamidine-HCl the methyl derivative3 b is obtained. Reaction of the codimer of malononitrile and methyl cyanoacetate (1 b) with formamidine yields the aminopyridine3 c, while acetamidine and benzamidine, resp. with1 b react to the 1,4-dihydro-4-pyrimidinylidene-methyl-cyanoacetates4 a-b.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00938285
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  • 6
    Electronic Resource
    Electronic Resource
    Synthesen mit Nitrilen, LXXV Zur Reaktivität der Dimeren von Malononitril und Cyanessigester gegenüber Dimethylformamid-dimethylacetal (1987)
    Springer
    Monatshefte für Chemie 118 (1987), S. 617-626 
    Details
    ISSN: 1434-4475
    Keywords: Cyanoacetate ; Dimethylformamide-dimethylacetal ; Malononitrile
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Reaction of malononitrile dimer (1) and the codimer from cyanoacetate and malononitrile (2) with dimethylformamide-dimethylacetal (DMFDMA) leads to the monocondensation products5 a, b. The isomeric codimer3, however, gives the amidine6. Ring closure reactions of5 a with ammonia and primary aliphatic and aromatic amines yield 2,4-diamino-3,5-pyridinedicarbonitriles7 a–j, in the case of5 b the 4-amino-1,2-dihydro-2-oxo-3,5-pyridinedicarbonitriles8 b–i. Reactions of1 and2 with an excess ofDMFDMA give the biscondensation products11 a, 11 b.11 b reacts with primary aromatic amines to give the pyridine derivatives13. The structure of13 was confirmed by hydrolytical cleavage to the dicyano-aminopyridone14. Treatment of13 with concentrated hydrochloric acid leads to the pyridopyrimidine derivatives15.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00809673
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  • 7
    Electronic Resource
    Electronic Resource
    Ozonolyse von Olefinen, III: Säurekatalysierte Ozonolyse von 3-Hexen-1,6-und 2-Penten-1,5-dicarbonylderivaten (1990)
    Springer
    Monatshefte für Chemie 121 (1990), S. 203-207 
    Details
    ISSN: 1434-4475
    Keywords: Ozonolysis ; 3-Hexene-1,6-dioic acid ; Glutaconic acid ; 3,3-Dimethoxypropanoate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The ozonolysis of mono-unsaturated compounds containing the structural element =CH-CH2-R [R=COOH, COOCH3, CH(OCH3)2] was investigated. Reductive ozonolysis of (E)-3-hexene-1,6-dioic acid gives methyl 3,3-dimethoxypropanoate (2), whereas ozonolysis of dimethyl (E)-3-hexene-1,6-dioate (1a) and (Z)-1,1,6,6-tetramethoxy-3-hexene (1b) in a methanolic solution of HCl leads to a mixture of2, dimethyl malonate (3 a) and 1,1,3,3-tetramethoxypropane (3 b). The homologuos derivatives, dimethyl glutaconate (4 a) and 1,1,5,5-tetramethoxy-2-pentene (4 b), were ozonized to give mixtures of2, 3, dimethyl oxalate (5), methyl 2,2-dimethoxyacetate (6 a), and 1,1,2,2-tetramethoxyethane (6 b). The ratios of the various reaction products were determined by gas chromatography. In each case the formation of the bifunctional derivatives2 and6 a was favoured.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00809533
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  • 8
    Electronic Resource
    Electronic Resource
    Cyanoacetaldehyde — New synthetic applications of an old compound syntheses with nitriles, XCI (1993)
    Springer
    Monatshefte für Chemie 124 (1993), S. 199-207 
    Details
    ISSN: 1434-4475
    Keywords: Cyanoacetaldehyde ; Hydrazones ; Cyanopyrazoles ; Aminopyrazoles
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Verschiedene Umsetzungen mit Cyanacetaldehyd (1), welcher durch Ozonolyse von (E)-1,4-Dicyanbuten oder Allylcyanid hergestellt wurde, werden beschrieben. Reaktion von1 mit Anilinen führt zu den β-Phenylaminoacrylnitrilen2a–e. Umsetzungen von1 mit Hydrazinen ergeben die entsprechenden Hydrazonderivate3a–e, welche unter alkalischen Bedingungen zu den 5-Aminopyrazolen4a–d cyclisiert werden können. Ein Aldol-ähnliches Kondensationsprodukt5a wird durch Reaktion von1 mit Natriumphenolat erhalten. Erhitzen von1 in Dimethylformamiddimethylacetal führt zur Bildung von (E)-3-Dimethylamino-2-formylpropennitril (6), ein wichtiges Zwischenprodukt für organische Synthesen. Die Struktur kann mit NOE-Experimenten geklärt werden. Reaktion von6 mit Hydrazinen führt zu 1-substituierten 4-Cyanpyrazolen7a–k.
    Notes: Summary Various reactions of cyanoacetaldehyde (1), freshly prepared by ozonization of (E)-1,4-dicyano-2-butene or allylcyanide, are described. Thus, conversion of1 with anilines gave β-phenylaminoacrylonitriles2a–e. Reaction of1 with hydrazines led to the corresponding hydrazones3a–e, which could be cyclized under alkaline conditions to 5-aminopyrazoles4a–d. An aldol-type condensation product5a could be obtained by reaction of1 with sodiumphenoxide. Treatment of1 with dimethylformamide-dimethylacetal led to the formation of (E)-3-dimethylamino-2-formylpropenenitrile (6), a very useful synthon in synthetic chemistry. For the determination of the structure of6 the method of steady state differential NOEs was used. Reaction of6 with hydrazines gave 1-substituted-4-cyanopyrazoles7a–k.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00808679
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  • 9
    Electronic Resource
    Electronic Resource
    Synthesen mit Nitrilen, LXVIII. 4-Dicyanmethylen-1,4-dihydropyrimidine und Pyrido[4,3-d]-pyrimidin-8-carbonitrile aus Enaminonitrilen (1983)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1983 (1983), S. 1107-1115 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses with Nitriles, LXVIII. - 4-Dicyanomethylene-1,4-Dihydropyrimidines and Pyrido [4,3-d]pyrimidine-8-carbonitriles from EnaminonitrilesReaction of “dimeric malononitrile” (1a) or 3-amino-2-cyano-crotononitrile (1b) with dimethyl-formamide dimethyl acetal gives the biscondensation products 2. Subsequent treatment of 2a with ammonia and 2b with primary aliphatic amines leads to 4-dicyanomethylene-1,4-dihydropyrimidines 3. There are several possible structures for the reaction products obtained from 2a and primary aliphatic and aromatic amines. The structure of the product from 2a and propylamine is confirmed by X-ray structure analysis as 5,6-dihydro-5-imino-6-propyl-4-(propylamino)pyrido[4,3-d] pyrimidine-8-carbonitrile (4c). Hydrolysis of 4 in acidic medium leads to the 5-oxo derivatives 5.
    Notes: Reaktion von “dimerem Malononitril” (1a) oder 3-Amino-2-cyancrotonsäurenitril (1b) mit Dimethylformamid-dimethylacetal ergibt die Biskondensationsprodukte 2. Die Umsetzung von 2a mit Ammoniak oder 2b mit primären aliphatischen Aminen führt zu 4-Dicyanmethylen-1,4-dihydropyrimidinen 3. Für die Reaktionsprodukte aus 2a mit primären aliphatischen und aromatischen Aminen sind mehrere isomere Strukturen möglich. Die Röntgenstrukturanalyse des Produktes von 2a mit Propylamin sichert die Struktur eines 5,6-Dihydro-5-imino-6-propyl-4-(propylamino)pyrido[4,3-d]pyrimidin-8-carbonitrils (4c). Saure Hydrolyse von 4 liefert die 5-Oxo-Derivate 5.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198319830704
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  • 10
    Electronic Resource
    Electronic Resource
    Synthesen mit Nitrilen, LXXVIII. Untersuchungen zur Struktur der Dimeren des Malononitrils, Cyanessigesters und Cyanacetamids (1987)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1987 (1987), S. 1131-1132 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Syntheses with Nitriles, LXXVIII. - Studies on the Structure of Dimers of Malononitrile, Cyanoacetate, and CyanoacetamideThe 13C- and 15N-NMR data of dimers and codimers of malononitrile, cyanoacetate, and cyanoacetamide 1-6 are discussed In the case of the unsymmetrically substituted derivatives 2, 4 and 5 it is possible to distinguish between E- and the predominantly existing Z-isomers. In the case of 2 the structure is confirmed by X-ray structure analysis.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198719870888
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