ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 11
    Electronic Resource
    Electronic Resource
    Arene hydrides, 4. Reaction of anthracene hydride (anion of 9,10-dihydroanthracene) with diaryl ketones. Base-induced fragmentation of the carbonyl adduct (1988)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 387-389 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: With benzophenone (1a) and fluorenone (1b) anthracene hydride (AH-) rapidly forms the anions 3a, b of the corresponding tertiary alcohols 4a, b, the intense colour of the reaction mixture indicating the presence of the ketyls 2a, b. Excess of AH- converts 3a, b into the diarylcarbinols. a mechanism is proposed for this ketone reduction.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19881210230
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 12
    Electronic Resource
    Electronic Resource
    Reactions with aziridines, 53.  -  Arene hydrides, 9. intermediate substitution in the formation of a benzylic anion by an aromatic radical anion as observed with 1-benzoyl-2-phenylaziridine (1990)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 2227-2230 
    Details
    ISSN: 0009-2940
    Keywords: Dihydroanthracene, benzylated ; Fragmentation ; Anthracenide Anthracene hydride ; Aziridines ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The reaction of the title compound 1 with anthracene hydride AH- or anthracenide A-' leads to the formation of the ben- zylic anion 9 by fragmentation of the first generated substi- tution intermediate 7 or 8. In the reactions with AH- the carb- anion 9 is completely trapped by protonation with dihydroan- thracene AH2 yielding the reduction product 3 (N-benzoyl-phenethylamine).phenethylamine). In reactions with A-' as well as with naph- thalenide N-' the carbanion 9 either abstracts a proton from the solvent THF (yielding 3) or adds to the benzoyl group of unreacted 1 which finally results in P-benzamido-ct-phenyl- propiophenone (6).
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19901231121
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 13
    Electronic Resource
    Electronic Resource
    Reaktionen mit Aziridinen (Aziranen), XXVI: Aminkatalysierte Amidoethylierungen von β-Dicarbonylverbindungen Eine einfache Synthese von 2-Methylpyrrol-1,3-dicarbonester (1981)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 114 (1981), S. 3599-3608 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Aziridines (Aziranes), XXVI: Amine Catalyzed Amidoethylation of β-Dicarbonyl Compounds Simple Synthesis of 2-Methylpyrrole-1,3-dicarboxylateEsters of nonsubstituted and monosubstituted malonic, cyanoacetic, and β-keto acids are easily C-amidoethylated by N-acylaziridines in the presence of triethylamine. In this amine catalyzed reaction the acylaziridines show different degrees of reactivity. Often the products cannot be obtained by the known amidoethylation procedure or but in smaller yields. The new product 3g may smoothly be converted to the pyrroline 9 and further to the 2-methylpyrrole-1,3-dicarboxylate 10. - Divergent from earlier results, the primary amidoethylation product can be isolated from the known sodium salt reaction of tert-butyl acetoacetate with nonbulky acylaziridines. This product is cleaved by trifluoroacetic acid with remarkable easiness to yield the corresponding amidoethyl derivative of acetone.
    Notes: Unsubstituierte und monosubstituierte Malonester, Cyanessigester und β-Ketoester werden in Gegenwart von Triethylamin durch N-Acylaziridine leicht am C amidoethyliert, dabei zeigt sich eine Reaktivitätsabstufung der N-Acylaziridine. Die Produkte sind oft durch die bisher bekannte Amidoethylierung nicht oder nicht in so guten Ausbeuten zugänglich. Das neue Produkt 3g läßt sich glatt zum Pyrrolin 9 und weiter zum 2-Methylpyrrol-1,3-dicarbonester 10 umwandeln. - Abweichend von bisherigen Ergebnissen kann man aus Acetessigsäure-tert-butylester nach der bekannten Natriumsalzmethode auch mit nichtsperrigen Acylaziridinen das Primärprodukt fassen, das mit Trifluoressigsäure bemerkenswert leicht zum entsprechenden Amidoethylderivat des Acetons gespalten wird.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19811141113
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 14
    Electronic Resource
    Electronic Resource
    Reaktionen mit Aziridinen, 36. Arenhydride, 2. SN2- und SET-Reaktionen von N-Acylaziridinen mit Diphenylmethanid und „Naphthalinhydrid“ (Anion von Dihydronaphthalin) (1986)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 119 (1986), S. 2050-2054 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Reactions with Aziridines, 36 Arene Hydrides 2. SN2 and SET Reactions of N-Acylaziridines with Diphenylmethanide and „Naphthalene Hydride“ (Anion of Dihydronaphthalene)Diphenylmethane is incompletely deprotonated by sodium naphthalenide in THF so that some „naphthalene hydride“ 4 (anion of 1,4-dihydronaphthalene) remains present in the deprotonation equilibrium. The generated diphenylmethanide anion 3a reacts with the N-acylaziridines 6a-c to form the expected amidoethyl derivatives 7a-c in yields of less than 50%. The formation of by-products from 6b and 6c can be rationlized on the basis of classic ionic mechanisms. However, for 6a the by-product N-ethylbenzamide clearly points to a SET mechanism with „naphthalene hydride“ 4 as the electron source and with the radical 8 as a hydrogen source.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19861190624
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 15
    Electronic Resource
    Electronic Resource
    Reactions with aziridines, 51: Ring opening of cis-2-Benzyl-3-phenyl-1-(phenylsulfonyl)aziridine by alkoxide. The first eliminative fission of an aziridine with uncharged nitrogen (1989)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 122 (1989), S. 1795-1797 
    Details
    ISSN: 0009-2940
    Keywords: Aziridines, regioselectivity of ring opening ; Allylamide-enamide isomerization ; Benzenesulfonamide, N-(1,3-diphenylallyl) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The title compound 2 can be ring-opened in three ways by alcoholic sodium alkoxide: nucleophilic substitutive opening in (the benzylic) position 3 [attack (a)] and in position 2 [attack (b)] as well as the novel nucleophilic eliminative opening which is initiated by deprotonation of the benzylic substituent [attack (c)]. The primary cleavage product 5 of attack (c) is an allylic sulfonamide that slowly isomerizes to give the elusive enamide 6, the precursor of the isolated ketone 7. Attack (a) predominates with methoxide and less so with ethoxide. Attack (c) increases with size (and basicity?) of the alkoxide and is the only detected reaction with tert-butoxide.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19891220928
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 16
    Electronic Resource
    Electronic Resource
    Reaktionen mit Aziridinen, 421) Die Regioselektivität der Ringöffnung von aktivierten 2,2-Dimethylaziridinen durch Carbanionen des β-Dicarbonyltyps. Einfluß der Größe des Nucleophils (1987)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 120 (1987), S. 1239-1244 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Aziridines,421). - The Regioselectivity of the Ring Opening of Activated 2,2-Dimethyhlaziridines by Carbanions of the Dicarbonyl Type. Influence of the Size of the NucleophileThe aziridine ring of the 1-acyl-2,2-dimethylaziridines 1a-c is cleaved abnormally (between N and CMe2) by the substituted ethyl cyanoacetates 3M,P (M=methyl, P=phenyl) in ethanolic ethoxide solution, while the ring is not cleaved by diethyl malonate (2H). Under the same conditions, 2,2-dimethyl-1-tosylaziridine (1d) is opened by malononitrile (4H), ethyl cyanoacetate (3H) 3M, and 2H in a predominant of exclusive normal manner (between N and CH2) with the relative portion of abnormal opening decreasing in the sequence 4H〉3H〉3M〉2H. The latter finding is rationalized by an influence of the size of the nucleophile (the respective carbanion) on an SN2 attack at the (“widened”) tert. C atom of 1d. A dominating abnormal opening of 1d (0% “normal products” from a 44% material balance of products) was observed with the largest anion (of 3P) of the series, pointing to a change in mechanism, presumable to SET. 1-Acyl-2-phenylaziridine 21 was opened at the benzylic C by the anion of 3P yielding the stereochemically uniform product 22.
    Notes: Die 1-Acyl-2,2-dimethylaziridine 1a-c werden durch die substituierten Ethyl-cyanacetate 3M,P (M=Methyl, P=Phenyl) in Ethanolat-Lösung anomal (zwischen N und CMe2) geöffnet, während Diethylmalonat (2H) den Aziridinring nicht öffnet. Unter gleichen Bedingungen wird 2,2-Dimethyl-1-tosylaziridin (1d) durch Malononitril (4H), Ethyl-cyanacetat (3H), durch 3M und 2H überwiegend bis ausschließlich normal geöffnet. Dabei nimmt der relative Anteil der anomalen Öffnung in der Reihenfolge 4H〉3H〉3M〉2H ab, was mit dem Einfluß der Größe des Nucleophils (jeweiliges Carbanion) auf einen SN2-Angriff am (“aufgeweiteten”) tert. C-Atom von 1d erklärt wird. Die mit dem größten Anion (von 3P) der Reihe beobachtete Dominanz der anomalen Öffnung von 1d (0% “normale Produkte” bei einer Bilanz von 44%) deutet auf einen Wechsel im Reaktionsmechanismus hin, vermutlich zu SET. 1-Acyl-2-phenylaziridin 21 wurde durch das Anion von 3P am Benzyl-C zum stereochemisch einheitlichen Produkt 22 geöffnet.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19871200720
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 17
    Electronic Resource
    Electronic Resource
    Reactions with aziridines, 46. Ring opening of stilbene imines by thiophenolate (1988)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 1353-1355 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Ring opening by thiophenolate of cis-trans pairs of stilbene imines proceeds stereospecifically irrespective of the kind of mono activation by the phenylsulfonyl group (1), by the benzoyl group (2), or by protonation of the aziridine base (3). In accordance with complete Walden inversion, the sole product from the cis isomer is always a diastereomer of the sole product from the trans isomer. The diastereomers obtained from 3 are correlated with the respective diastereomers obtained from 2.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19881210722
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 18
    Electronic Resource
    Electronic Resource
    Reactions with Aziridines, 45. - Arene Hydrides, 5. Reversibility of Carbonyl Attack on N-Benzoylaziridines Prior to Ring Opening by Carbanions. - Strong Influence of the Gegen Ion (1988)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 121 (1988), S. 1349-1352 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaktionen mit Aziridinen, 451. - Arenhydride,5 2. - Reversibilität des Carbonylangriffs bei N-Benzoylaziridinen vor der Ringöffnung durch Carbanionen. - Starker Gegenion-EinflußEin früherer Bericht hatte gezeigt, daß Anthracenhydrid AH- bzw. das Xanthenylanion X- zuerst die Carbonylgruppe von N-Benzoylaziridinen angreifen, da in frühen Stadien der Reaktion ein Abstoppen mit Protonen hohe Ausbeuten an Benzoyldihydroanthracen 3 bzw. Benzoylxanthen 11 liefert. Die entsprechenden Carbonyladdukt-Zwischenstufen 2 und 10 waren als Vorläufer von Produkten angesehen worden, die aus einer Homolyse des Aziridinringes hervorgehen. Es wird jetzt gezeigt, daß Abstoppen der Reaktion zwischen AH- bzw. X- und den N-Benzoylaziridinen 1a, b mit Methyliodid oder Aroylchloriden hohe Ausbeuten an Produkten ergibt, die sich von AH- (bzw. X-) oder 1a, b ableiten. Dies zeigt an, daß 2 (bzw. 10) im Gleichgewicht mit AH- (bzw. X-) und 1a, b stehen. Untersuchung des Gegenion-Einflusses bei X- ergab, daß die Gleichgewichtskonzentrationen an 10-Na+ viel niedriger waren als diejenigen an 10-Li+, während gleichzeitig die Ringöffnung von 1a mit X-Na+ deutlich schneller war als mit X-Li+. Dieser Befund legt die Vermutung nahe, daß im Gegensatz zur früheren Annahme die Gleichgewichtskonzentrationen an X- und 1a für die (homolytische) Ringöffnung verantwortlich sind.
    Notes: A previous report had shown that anthracene hydride AH- or the xanthenyl anion X-, respectively, at first add to the carbonyl group of N-benzoylaziridines since high yields of benzoyl dihydroanthracene 3 or benzoyl xanthene 11 were obtained when in early stages the reaction was quenched with protons. The respective intermediate carbonyl adducts 2 and 10 had been considered to be precursors of products resulting from homolysis of the aziridine ring. It is now shown that quenching of the reaction between AH- or X- and N-benzoylaziridines 1a, b with methyl iodide or aroyl chlorides results in substantial yields of products derived from either AH- (or X-) or 1a, b. This indicates that 2 (or 10) are in equilibrium with AH- (or X-) and 1a, b. Study of the gegenion influence with X- revealed that the equilibrium concentrations of 10-Na+ were much lower than those of 10-Li+ while simultaneously the ring opening of 1a was distinctly faster with X-Na+ than with X-Li+. This finding suggests that, contrary to the previous assumption, the equilibrium concentrations of X- and 1a are responsible for the (homolytic) ring opening.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19881210721
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 19
    Electronic Resource
    Electronic Resource
    Reaktionen mit Aziridinen, XIII. Ringöffnung von 1-(Diphenylcarbamoyl)aziridin durch Anionen von β-Dicarbonylverbindungen (1976)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 109 (1976), S. 2005-2013 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Aziridines, XIII. Ring Opening of 1-(Diphenylcarbamoyl)aziridine by Anions of β- Dicarbonyl CompoundsDi-ethyl malonate, di-tert_butyl malonate, ethyl acetoacetate, tert-butyl acetoacetate, ethyl cyanoacetate, three substituted ethyl cyanoacetates and malononitrile are alkylated with 2-(3,3-di-phenylureido)ethyl groups by ring opening of 1-(diphenylcarbamoyl)aziridine (1c) in the presence of alkoxide. The new products are mono (6a-c, e-h, j) or dialkylated (8b, d, e, i, k, l). In two cases the products have been altered by secondary reaction with the alcohol used as solvent: by deacetylation (8d→8k) and by addition of alcohol to a nitrile group yielding the imidate (8i→8I).
    Notes: Malonsäure-diäthylester, Malonsäure-di-tert-butylester, Acetessigsäure-äthylester, Acetessigsäure-tert-butylester, Cyanessigsäure-äthylester, drei substituierte Cyanessigsäure-äthylester und Malononitril werden in Gegenwart von Alkoholat durch Ringöffnung von 1-(Diphenylcarbamoyl)aziridin (1c) mit 2-(3,3-Diphenylureido)äthyl-Resten Zweifach (8b, d, e, i, k, l) oder einfach (6a-c, c, e-h, j) substituiert. Die Produkte waren in zwei Fällen durch Sekundärreaktion mit dem Solvens Äthanol verändert: durch Entacylierung (8d → 8k) bzw. durch Alkoholaddition an eine Nitrilgruppe zum Imidoester (8i → 8l).
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19761090606
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 20
    Electronic Resource
    Electronic Resource
    Reaktionen mit Aziridinen, XV: Amidoethylierung von Triarylmethanen und Diarylaminen mit 1-Acylaziridinen (1978)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 111 (1978), S. 502-515 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reactions with Aziridines, XV: Amidoethylation of Triarylmethanes and Diarylamines with 1-AcylaziridinesThe N-acyl-3,3,3-triphenylpropylamines 4a-d and the N-acyl-3,3-diphenyl-3-(2-pyridyl)propylamines 7a-d are obtained in good yields by ring opening of the 1-acylaziridines 2a-d with tritylsodium (1) or 2-azatritylsodium (5), respectively. Side and secondary products such as the acylaminoethyl compounds 11 and 16 and the ureas XCH2CH2NH-CO-NHCH2CH2Y (13, 14, 15) are formed, if the 1-acylaziridines 2a, b with an acyl moiety XCO having a nucleofuge radical X react with azatritylsodium at room temperature or above. The sodium derivatives of diphenylamine and carbazole react analogously with the acylaziridines 2b and 2a.
    Notes: Durch Ringöffnung der 1-Acylaziridine 2a-d mit Tritylnatrium (1) bzw. 2-Azatritylnatrium (5) lassen sich die N-Acyl-3,3,3-triphenylpropylamine 4a-d bzw. die N-Acyl-3,3-diphenyl-3-(2-pyridyl)propylamine 7a-d in guten Ausbeuten gewinnen. Werden die 1-Acylaziridine 2a, b, deren Acylrest XCO einen nucleofugen Rest X besitzt, mit 2-Azatritylnatrium bei Raumtemperatur oder darüber umgesetzt, so entstehen Neben- und Folgeprodukte wie die Acylaminoethylverbindungen 11 und 16 und Harnstoffverbindungen XCH2CH2NH—CO—NHCH2CH2Y (13, 14, 15). Die Natriumverbindungen von Diphenylamin bzw. Carbazol reagieren mit den Acylaziridinen 2b bzw. 2a analog.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19781110209
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...