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  • 1
    Electronic Resource
    Electronic Resource
    Gekreuzt-konjugierte polychlorierte Cycloheptatrienderivate aus Octachlorcycloheptatrien und Hexachlortropon (1988)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 1595-1600 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cross-Conjugated Polychlorinated Derivatives of Cycloheptatriene from Octachlorocycloheptatriene and HexachlorotroponeA new convenient synthesis of hexachlorotropone (6) and some condensation reactions of 6 are described, yielding novel polychlorinated cross-conjugated derivatives of cycloheptatriene. Treatment of octachlorocycloheptatriene (5) with benzene/CF3SO3Ag and phenylmalononitrile (28) leads to the first stable [1.6.7]quinarenes 19 and 29, respectively. The structure of 19 is proved by X-ray diffraction and a mechanism is proposed for the reaction. The influence of polychlorination on stability and electronic spectra is discussed.
    Notes: Wir beschreiben eine neue, ergiebige Synthese von Hexachlortropon (6) und einige Kondensationsreaktionen von 6 zu neuen polychlorierten, gekreuzt konjugierten Cycloheptatrienderivaten. Umsetzungen von Octachlorcycloheptatrien (5) mit Benzol/CF3SO3Ag bzw. mit Phenylmalononitril (28) führen zu ersten stabilen [1.6.7]Chinarenen 19 und 29. Die Struktur von 19 wird mit Hilfe einer Röntgenstrukturanalyse bewiesen und ein Bildungsweg vorgeschlagen. Der Einfluß der Polychlorierung auf Stabilität und Elektronenspektren wird diskutiert.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19881210910
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  • 2
    Electronic Resource
    Electronic Resource
    15N-NMR-Studien der Tautomerie in N-monosubstituierten Amidinen und in N,N′-Diphenylguanidin (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 1101-1104 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 15N NMR Studies of the Tautomeric Equilibrium of N-Monosubstituted Amidines and of N,N′-Diphenylguanidine15N NMR data are reported for tautomeric N-monosubstituted amidines 1a and b and for N,N′-diphenylguanidine (6). In order to elucidate the position of the tautomeric equilibrium, the nitrogen resonances of the salts of 1a, b and 6 were also determined. For comparison, chemical shifts δ15N were measured of non-tautomeric amidines 2 - 5. The preferred tautomers for N-phenylbenzamidine (1a) and for 6 have the C=N double bond conjugated with the phenyl group. Replacement of an NH proton with an alkyl group, as in 1b, has little effect on the tautomeric equilibrium of amidines.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190331
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  • 3
    Electronic Resource
    Electronic Resource
    Zur Tautomerie von O-Alkylidenpropandinitril- und O-Alkylidencyanamid-Gruppen in O-substituierten Acetylacetonen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 669-675 
    Details
    ISSN: 0009-2940
    Keywords: Acetylacetonates, O-substituted ; (Alkenyloxymethylene)cyanamide derivatives ; (Alkenyloxymethylene)-propanedinitrile derivatives ; Tautomerism ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Tautomerism of O-Alkylidenepropanedinitrile and O-Alkylidenecyanamide Groups in O-Substituted AcetylacetonesReaction of the sodium salt of acetylacetone (1) with (α-chlorobenzylidene)propanedinitrile (2, R = Ph) leads to the C-substitution product 4 as the cis-enol. The trans-enol 5 is only obtained as an intermediate (e.g. photochemically) yielding immediately the 2-pyridone 6. Acetylacetone (7) as such reacts with 2 (R = Ph) or with N-cyanobenzimidoyl chloride (9) in the presence of triethylamine/DMAP to give the O-substitution products 8 and 10 as mixtures of their E/Z-isomers. The Z-isomers show a rapid degenerate (O → O) migration. By heating, 8Z rearranges irreversibly to the benzoic acid enol ester 11. 3-Phenylacetylacetone or its thallium(I) salt 16 reacts with (1-chloroalkylidene)propanedinitriles 2 or with N-cyanobenzimidoyl chloride (9) to yield the O-substitution products 14, 15, 17a, and 17b. 8Z, 17a, and 17b were investigated by DNMR spectroscopy.
    Notes: Die Umsetzung des Natriumsalzes von Acetylaceton (1) mit (α-Chlorbenzyliden)propandinitril (2, R = Ph) ergibt das C-Substitutionsprodukt 4 als cis-Enol. Das nur als Zwischenstufe (z. B. photochemisch) erhältliche trans-Enol 5 cyclisiert sofort zum 2-Pyridon 6. Acetylaceton (7) selbst liefert mit 2 (R = Ph) oder mit N-Cyanbenzimidoylchlorid (9) in Gegenwart von Triethylamin/DMAP die O-Substitutionsprodukte 8 und 10 als E/Z-Isomerengemische. Die Z-Isomere zeigen eine schnelle entartete (O → O)-Wanderung. 8Z lagert sich bei längerem Erhitzen irreversibel in den Benzoesäure-enolester 11 um. 3-Phenylacetylaceton oder sein Thallium(I)-Salz 16 reagieren mit (1-Chloralkyliden)propandinitrilen 2 oder N-Cyanbenzimidoylchlorid (9) zu den O-Substitutionsprodukten 14, 15, 17a und 17b. 8Z, 17a und 17b werden DNMR-spektroskopisch untersucht.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220413
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  • 4
    Electronic Resource
    Electronic Resource
    15N-NMR-Studien an 2-Hydroxyguanidinen und Amidoximen (1985)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 118 (1985), S. 3481-3491 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 15N NMR Studies of 2-Hydroxyguanidines and Amide OximesChemical shifts δ 15N and coupling constants 1J(15N, 1H) have been determined for several 2-hydroxyguanidines 1 and amide oximes 4. Structures and protonation sites of these compounds are discussed. The synthesis of 1-monosubstituted 2-hydroxyguanidines has been improved.
    Notes: Die chemischen Verschiebungen δ 15N und die Kopplungskonstanten 1J(15N, 1H) mehrerer 2-Hydroxyguanidine 1 und Amidoxime 4 wurden bestimmt. Die Strukturen und der Ort der Protonierung dieser Verbindungen werden diskutiert. Die Synthese 1-monosubstituierter 2-Hydroxyguanidine wurde verbessert.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19851180905
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  • 5
    Electronic Resource
    Electronic Resource
    Bis(sulfonyl)cyclopentadiene (1986)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1986 (1986), S. 1268-1280 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Bis(sulfonyl)cyclopentadienesDichloro-1,3-bis(sulfonyl)cyclopentanes (e.g. 12, 14, 19) have been obtained by addition of sulfenyl chlorides to cyclopentadiene followed by oxidation. The regio and stereoselectivity of this reaction depends on the sequence of their individual steps. Elimination of HCl leads to the formation of the 1,3-bis(sulfonyl)cyclopentadienides 2 which are protonated to give the stable 1,3-bis(sulfonyl)cyclopentadienes 3. 3-Chloro-4,5-bis(sulfonyl)cyclopentenes 24 are formed at - 50 to - 60°C from thallium(I) cyclopentadienide (20) and sulfenyl chlorides with subsequent oxidation. Elimination of HCl gives rise to the 1,2-bis(sulfonyl)cyclopentadienides 26 which yield the Diels-Alder adducts 27 on acidification.
    Notes: Dichlor-1,3-bis(sulfonyl)cyclopentane (z.B. 12, 14, 19) sind durch Addition von Sulfensäurechloriden an Cyclopentadien und nachfolgende Oxidation erhältlich. Regio- und Stereoselektivität hängen von der Reihenfolge der einzelnen Reaktionsschritte ab. Durch HCl-Eliminierung erhält man daraus die 1,3-Bis(sulfonyl)cyclopentadienide 2, die beim Ansäuern die stabilen 1,3-Bis(sulfonyl)cyclopentadiene 3 liefern. 3-Chlor-4,5-bis(sulfonyl)cyclopentene 24 entstehen bei - 50 bis - 60°C aus Thallium(I)-cyclopentadienid (20) und Sulfensäure-chloriden mit anschließender Oxidation. HCl-Eliminierung führt zu den 1,2-Bis(sulfonyl)cyclopentadieniden 26, die beim Ansäuern in die Dimeren 27 übergehen.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198619860713
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  • 6
    Electronic Resource
    Electronic Resource
    Cyclopenta[C]pyran und sein 6-tert-Butyl-Derivat (1988)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1988 (1988), S. 855-860 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cyclopenta[C]pyran and Its 6-tert-Butyl DerivativeThree-step syntheses of the hitherto unknown cyclopenta[C]pyran (2) and its 6-tert-butyl derivative 12 are described. The 1H-NMR, 13C-NMR, and electronic spectra of the lemon-yellow isooxalenes are compared with those of other pseudoazulenes.
    Notes: Wir beschreiben dreistufige Synthesen des bisher unbekannten Cyclopenta[C]pyrans und dessen 6-tert-Butyl-Derivats 12. Die 1H-NMR-, 13C-NMR- und Elektronenspektren der zitronengelben Isooxalene werden mit denen anderer Pseudoazulene verglichen.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198819880907
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