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  • 1
    Electronic Resource
    Electronic Resource
    The Inversion of the Amino Group in Vinylamine, a Flexible Model TreatmentA preliminary account of this work was given at the meeting of the Swiss Chemical Society in Geneva, October 9, 1976. (1978)
    New York, NY : Wiley-Blackwell
    Helvetica Chimica Acta 61 (1978), S. 1418-1426 
    Details
    ISSN: 0018-019X
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Flexible model results for the —NH2 inversion in vinylamine are compared with microwave data published by Lovas et al. [3]. The information available on the spacing of inversion levels is found to be sufficient to rule out a planar equilibrium structure. Shifts of rotational constants upon excitation of the inversion are calculated for two predicted paths of motion derived from PRDDO geometry optimization results obtained by MiiIler & Brown [2]. Partial geometry optimization yields a path inconsistent with experiment but the path obtained from complete optimization produces shifts in excellent agreement with the observed shifts. A potential energy function compatible with experimental data on spacing of inversion levels is calculated from the observed inertia defects. The inversion angle at equilibrium is slightly smaller than the angle predicted from PRDDO calculations, and the barrier to inversion, ΔV = 1.08 ± 0.07 kcal/mol, is approximately half the PRDDO value.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/hlca.19780610426
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  • 2
    Electronic Resource
    Electronic Resource
    Synthese von Zuckerestern der Lysergsäure und 9,10-Dihydrolysergsäure (1979)
    New York, NY : Wiley-Blackwell
    Journal für Praktische Chemie/Chemiker-Zeitung 321 (1979), S. 171-174 
    Details
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis of Sugar Esters of Lysergic Acid and 9, 10-Dihydrolysergic Acid
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/prac.19793210126
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  • 3
    Electronic Resource
    Electronic Resource
    Darstellung von 5-Hydroxy-1,7-naphthyridin (1979)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1979 (1979), S. 443-445 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis of 5-Hydroxy-1,7-naphthyridineN-(p-Toluenesulfonyl)glycine ester 1b reacts with 2-(bromomethyl)nicotinic ester 2 to form the nicotinic acid derivative 3b. Cyclization of 3b, by elimination of sulfinic acid, leads to the 1,7-naphthyridine derivative 7, from which the title compound 8 is formed.
    Notes: N-(p-Toluolsulfonyl)glycinester 1b reagiert mit 2-(Brommethyl)nicotinsäureester 2 zum Nicotinsäurederivat 3b. Dieses läßt sich unter Eliminierung von Sulfinsäure zum 1,7-Naphthyridin-derivat 7 cyclisieren, aus dem die im Titel genannte Verbindung 8 erhalten wird.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.197919790402
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  • 4
    Electronic Resource
    Electronic Resource
    Malondiamidine, II. Kondensationsreaktionen mit aromatischen Aldehyden (1979)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1979 (1979), S. 1291-1299 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Malondiamidines, II. - Condensation Reactions with Aromatic AldehydesCondensation of malondiamidines 4 with double molar quantities of aldehydes 1 leads to the novel 2,5-disubstituted 4,6-diaminopyrimidines 6a - n. The reaction course (aminal formation, Knoevenagel condensation, and sigmatropic 1,5-hydrogen shift) is discussed. Use of salicylaldehyde in this reaction furnishes the benzopyrano[2,3-d]pyrimidines 13a - c by additional elimination of the amino component. The benzopyrano[2,3-d]pyrimidine 16 is obtained by condensation of salicylaldehyde and 3-amino-3-(1-pyrrolidinyl)acrylonitrile (15) in a 2:1 molar ratio.
    Notes: 2,5-Disubstituierte 4,6-Diaminopyrimidine 6a - n werden durch Kondensation von Malondiamidinen 4 mit Aldehyden 1 im Molverhältnis 1:2 erhalten. Der Chemismus dieser Reaktion (Aminalbildung, Knoevenagel-Kondensation, sigmatrope 1,5-Wasserstoffverschiebung) wird diskutiert. Salicylaldehyd als Aldehydkomponente liefert unter analogen Bedingungen unter zusätzlicher Eliminierung der Aminkomponente die Benzopyrano[2,3-d]pyrimidine 13a - c. Das Benzopyrano [2,3-d]pyrimidin 16 wird auch durch Kondensation von Salicylaldehyd und 3-Amino-3-(1-pyrrolidinyl)acrylonitril (15) gewonnen.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.197919790904
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  • 5
    Electronic Resource
    Electronic Resource
    Synthesen von (-)-(S)- und (+)-(R)-Goniothalamin; absolute Konfiguration des natürlichen (+)-Goniothalamins (1979)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1979 (1979), S. 484-491 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses of (-)-(S)- and (+)-(R)-Goniothalamin; Absolute Configuration of the Naturally Occurring (+)-Goniothalamin(-)-(S)-Goniothalamin and its naturally occurring (+)-(R)-enantiometer were synthesised from configurationally defined precursors. The absolute configurations were additionally confirmed by ozonolysis to (-)-(S)- and (+)-(R)-malic acid. The absolute configuration given for the compound in the literature is thus corrected.
    Notes: (-)-(S)-Goniothalamin und das (+)-(R)-Enantiomer wurden aus konfigurativ definierten Vorstufen synthetisiert. Die absoluten Konfigurationen wurden zusätzlich durch Ozonabbau zu (-)-(S)- und (+)-(R)-Äpfelsäure bestätigt. Die in der Literatur angegebene absolute Konfiguration des Naturstoffs wird berichtigt.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.197919790409
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  • 6
    Electronic Resource
    Electronic Resource
    Sila-Pharmaka, 181) Derivate des 1-(4-Chlorphenyl)silacyclohexans mit 3-(Diethylamino)propyl- und 2-(Diethylamino)ethyl-Gruppierungen (1979)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1979 (1979), S. 1915-1924 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Sila-Drugs, 181). - Derivatives of 1-(4-Chlorophenyl)silacyclohexane with 3-(Diethylamino)propyl and 2-(Diethylamino)ethyl GroupsThe preparation of the compounds 3a (and 3b) and 10, which derive from 1-(4-chlorophenyl)-1-(2-diethylaminoethoxy)silacyclohexane (sila-chlorophencyclane, IIa), is described. Compound 3b has been investigated pharmacologically and toxicologically. The biological properties of 3b and those of IIa (and chlorophencyclane) and its hydrochloride IIb are compared.
    Notes: Die Darstellung der Verbindungen 3a (sowie 3b) und 10, die sich vom 1-(4-Chlorphenyl)-1-(2-diethylaminoethoxy)silacyclohexan (Sila-Chlorphencyclan, IIa) ableiten, wird beschrieben. Die Verbindung 3b wurden pharmakologisch und toxikologisch untersucht. Die biologischen Eigenschaften von 3b wurden mit denen von IIa (sowie Chlorphencyclan) und seinem Hydrochlorid IIb verglichen.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.197919791128
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  • 7
    Electronic Resource
    Electronic Resource
    Imin-Enamin-Tautomerie, V1) Lösungsmittel- und Temperaturabhängigkeit der Thioimidsäureester/Keten-S,N-acetal-Tautomerie (1975)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1975 (1975), S. 36-40 
    Details
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Imine-Enamine Tautomerism, V1). - Solvent- and Temperature-dependence of Thioimidoate/Ketene S,N-Acetal TautomerismI n solution N-aryl(thioimidoates) 2a exist predominantly in the ketene S,N-acetal form. The tautomeric equilibrium depends on the solvent and temperature. The quantity of the chelate ketene S,N-acetal 2b decreases with increasing polarity and ability of the solvent to form intermolecular hydrogen bonds. - The equilibrium constants and the values of the thermo-dynamic parameters ΔG, ΔH und Δ,S of the compound 2 (Rl = 4-Br, R* = CH3) have been determined in two solvents of different polarity by IH-NMR measurements. An increase in temperature and consequent decrease in entropy leads to destabilization of the ketene S,N-acetal in the tautomerism 2a ⇌ 2b.
    Notes: Die N-Aryl(thioimidsäure)ester 2a liegen in Lösung überwiegend in der tautomeren Keten-S,N-acetalform 2b vor. Das Tautomeriegleichgewicht ist lösungsmittel- und temperatur-abhängig. Mit zunehmender Polarität und zunehmender Befähigung des Lösungsmittels zur Ausbildung intermolekularer Wasserstoffbrücken sinkt der Gehalt des chelatisierten Keten-S,N-acetals 2b. - In zwei Lösungsmitteln unterschiedlicher Polarität wurden für die Verbindung 2 (R1 = 4-Br, R2 = CH3) 1H-NMR-spektroskopisch die Gleichgewichtskonstanten und die Werte der thermodynamischen Größen ΔG, ΔH und Δ,S bestimmt. Steigende Temperatur führt wegen der Entropieabnahme bei der Tautomerisierung 2a ⇌ 2b ebenfalls zur Destabilisierung des Keten-S,N-acetals.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.197519750104
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  • 8
    Electronic Resource
    Electronic Resource
    α-Heterosubstituierte Organyllithiumverbindungen durch Selen/Lithium-Austausch; gezielte Kopplung von Carbonyl-verbindungen (1977)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1977 (1977), S. 846-858 
    Details
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: α-Heterosubstituted Organyllithium Compounds by Selenium/Lithium-Exchange; Directed Coupling of Carbonyl CompoundsThe preparation of phenylseleno derivatives 1-4 and 6 is described. Se/Li-exchange with butyl- and tert-butyllithium removes the heteroatom free substituent from 1-3 and 8a; the sulfur derivative 10a undergoes the same transformation. The α-seleno- and α-thioalkyl-lithium derivatives 5 and 11 are generated in high yields from 4 and 6, respectively, as shown by their reactions with carbonyl compounds to give alcohols 12 and 16. According to scheme 1, the allylic alcohols 17, 18, and 20, as well as the olefin 21 and the epoxide 22 are obtained.
    Notes: Die Phenylselenderivate 1-4 und 6 wurden hergestellt.  -  Während beim Versuch der Transmetallierung von 1-3 sowie 8a mit Butyl- oder tert-Butyllithium stets der heteroatomfreie Substituent am Selen ausgetauscht wird, was auch beim Thioether 10a der Fall ist, entstehen aus 4 und 6 die α-Seleno- und α-Thioalkyllithiumderivate 5 bzw. 11. Dies wird durch deren Umsetzung zu den Alkoholen 12 und 16 bewiesen.  -  Nach Schema 1 wurden die Allylalkohole 17, 18 und 20, sowie das Olefin 21 und das Epoxid 22 synthetisiert.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.197719770514
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  • 9
    Electronic Resource
    Electronic Resource
    Synthesen mit α-metallierten Isocyaniden, XXXVIII. Trialkylmethyl-substituierte Glycine und Pyrrol-2,4-dicarbonsäureester aus 2-Isocyanacrylsäureestern und Carbanionen (1977)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1977 (1977), S. 1174-1182 
    Details
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses with 2-Metalated Isocyanides, XXXVIII. - Trialkylmethyl Substituted Glycines and Pyrrole-2,4-dicarboxylic Esters from 2-Isocyanoacrylic Esters and CarbanionsThe following Michael additions of carbanions to 2-isocyanoacrylic esters 2 are described: 1. The addition of Grignard compounds 4 to give 2-isocyano-2-(trialkylmethyl)ethanecarboxylic esters 5 which on hydrolysis form trialkylmethyl-substituted glycines (type 6 or 7); 2. the addition of ethyl lithioisocyanoacetate (8) to give 3-substituted diethyl pyrrole-2,4-dicarboxylates 11; and 3. the addition of diethyl sodiomalonate to form triethyl 1-isocyano-2,2-dimethylpropane-1,3,3-tricarboxylate (14).
    Notes: Folgende Michael-Additionen von Carbanionen an 2-Isocyanacrylsäureester 2 werden beschrieben: 1. die Addition von Grignard-Verbindungen 4 zu 2-Isocyan-2-(trialkylmethyl)-ethansäureestern 5, welche zu Trialkylmethyl-substituierten Glycinen (Typ 6 oder 7) hydrolysierbar sind, 2. die Addition von Lithioisocyanessigsäure-ethylester (8), die im Endeffekt 3-substituierte Pyrrol-2,4-dicarbonsäurediester 11 liefert und 3. die Addition von Natrium-malonsäureester an 2a, welche zu 1-Isocyan-2,2-dimethylpropan-1,3,3-tricarbonsäure-triethylester (14) führt.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.197719770714
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  • 10
    Electronic Resource
    Electronic Resource
    Synthesen mit α-metallierten Isocyaniden, XXXIX. 2-Imidazoline aus α-metallierten Isocyaniden und Schiff-Basen; 1,2-Diamine und 2,3-Diaminoalkansäuren (1977)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1977 (1977), S. 1183-1193 
    Details
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses with α-Metalated Isocyanides, XXXIX - 2-Imidazolines from α-Metalated Isocyanides and Schiff Bases; 1,2-Diamines and 1,2-Diaminoalkanoic acidsα-Metalated isocyanides 1 react with Schiff bases 5 to give via the intermediates 6 and 7 2-unsubstituted 2-imidazolines 8. The intermediate 2-metalated 2-imidazolines 7 can be trapped with electrophiles to give 2-substituted 2-imidazolines (for instance 9). - Alkyl 2-imidazoline-4-carboxylates 8f-o can be obtained alternatively from alkyl 2-isocyanoacrylates 11a,b and primary amines or ammonia. - On acides hydrolysis 2-imidazolines 8 give 1,2-diamines 13 or 2,3-diaminoalkanoic acids 14.
    Notes: α-Metallierte Isocyanide 1 reagieren mit Schiff-Basen 5 über die Zwischenstufen 6 und 7 zu 2-unsubstituierten 2-Imidazolinen 8. Die 2-metallierten Imidazoline vom Typ 7 können mit Elektrophilen zu 2-substituierten 2-Imidazolinen (z. B. 9) umgesetzt werden. - 2-Imidazolin-4-carbonsäureester 8f-o erhält man alternativ aus 2-Isocyanacrylsäureestern 11a,b und primären Aminen oder Ammoniak. - Die 2-Imidazoline 8 liefern bei der Hydrolyse 1,2-Diamine 13 oder 2,3-Diaminoalkansäuren 14.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.197719770715
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