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
  • 1
    Electronic Resource
    Electronic Resource
    Utilization of Industrial Waste Materials, 7. - Synthesis of New, Chiral β-sec-Amino Alcohols - Regio- and Diastereoselective α-Hydroxyalkylation of (1R,5R)-2-Azabicyclo[3.3.0]octane (1997)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1997 (1997), S. 563-571 
    Details
    ISSN: 0947-3440
    Keywords: Amino alcohols ; Chiral α-amino carbanions ; Diastereoselective α-aminoalkylation ; Proline analogues ; Enantioselective borane reduction ; Chiral auxiliaries ; Waste prevention ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New, chiral β-sec-amino alcohols 3a-d, 4a-e, and 5a-h have been synthesized from the enantiomerically pure amine (all-R)-2a. For the diastereo- and regioselective α-hydroxyalkylation of the chiral (all-R)-N-nitroso-2-azabicyclo[3.3.0]octane (all-R)-2d, Seebach's “one pot” method was chosen. The versatile nucleophilic intermediate reacts regio-and stereoselectively with a variety of electrophiles to afford 3-substituted pyrrolidine derivatives, e.g. (erythro)-(αR,βS)-amino alcohol frameworks with four sterically crowded stereogenic centers, and (βS)-configured tricyclic structures with a cycloalkynol building block (see formulae 3a-d, 4a-e, and 5a-h). Alkylation products are obtained in fair yields with a high degree of stereoselectivity (diastereomeric ratios dr up to 93:7). A mechanistic interpretation of the stereochemical course of this reaction is presented. - This is a further example of the synthesis of interesting new chiral ligands from the industrial waste material (all-R)-2-azabicyclo[3.3.0]octane-3-carboxylic acid benzyl ester (all-R)-1a. The catalytic ability of selected (erythro)- and new, related stereoisomeric amino alcohol structures were tested in the enantioselective borane reduction using the prochiral acetophenone as model substrate (enantiomeric excesses ee up to 86%).
    Additional Material: 8 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.199719970318
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Utilization of industrial waste materials, 5. Synthesis of new, chiral 1,3,2-oxazaphospholidine-borane complexes and attempts to apply them in the stereoselective synthesisDedicated to Prof. Friedrich Asinger on the occasion of his 88th birthday. (1995)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1995 (1995), S. 2123-2131 
    Details
    ISSN: 0947-3440
    Keywords: β-Amino alcohols ; Organophosphorus compounds ; Methoxyphosphane borane complexes ; Enantioselective borane reduction ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: New, chiral 1,3,2-oxazaphospholidine-borane complexes 3a-b and 8a-d were synthesized from the β-amino alcohols 1a-b and 6a-d. The borane complexes 3, 8a, 8c, and 8d were allowed to react with different organolithium compounds and afforded the corresponding aminophosphane-borane complexes 4a-c and 9a-g. Acid methanolysis of those complexes led to the formation of the phosphinite-borane complexes 5a-c. This is a further example of the utilization of the industrial waste material (all-R)-2-azabicyclo-[3.3.0]octane-3-carboxylic acid. The catalytic efficiency of the chiral 1,3,2-oxazaphospholidine-borane complexes 3a, 3b, and 8c was examined in the enantioselective borane reduction of some ketones.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.1995199512298
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Organische Schwefelverbindungen, VII. Photochemische α-Spaltung von Thiobenzoesäure-S-p-tolylestern in Lösung (1974)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 107 (1974), S. 2319-2325 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organosulfur Compounds, VII. Photochemical α-Cleavage of S-p-Tolyl Thiobenzoates in SolutionBy photolysis of some tolylesters 1 of donorsubstituted thiobenzoic acids the S-aroyl bonds are cleaved. Aroyl and thiyl radicals, formed through α-cleavage, are stabilized by aldehyde (2) and disulfide formation (4. In three cases, benzils (3) are also formed. Thia-photo-Fries rearrangements are not observed. Photopolymerizations of vinyl monomeres in film and in block are initiated by the studied α-ketosulfides 1.
    Notes: Bei der Photolyse von Tolylestern 1 donatorsubstituierter Thiolbenzoesäuren werden die S-Aroyl-Bindungen gespalten. Die durch α-Spaltung gebildeten Aroyl- und Thiylradikale stabilisieren sich durch Aldehyd- (2) bzw. Disulfidbildung (4). In drei Fällen entstehen auch Benzile (3). Thia-Photo-Fries-Umlagerungen werden nicht beobachtet. Photopolymerisationen von Vinylmonomeren im Film und im Block werden durch die untersuchten α-Ketosulfide 1 initiiert.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19741070716
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Organische Schwefelverbindungen, VIII. Bildung von Thiophenen durch Pyrolyse von Dihydrothiopyranen, Reaktionen der Diels-Alder-Addukte aus Thiofluorenon und 1,3-Butadienen in der Hitze und unter Elektronenstoß (1974)
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 107 (1974), S. 2931-2937 
    Details
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Organosulfur Compounds, VIII. Formation of Thiophenes by Pyrolysis of Dihydrothiopyrans, Reactions of Diels-Alder Adducts from Thiofluorenone and 1,3-Butadienes under Heating and Electron-Impact ConditionsThiofluorenone (1) reacts with 2,3-dimethyl- and 2,3-diphenyl-1,3-butadienen to give the Diels-Alder adducts 2a and 2b respectively. The adducts 2a and 2b, thermally stable either in solution or in the solid, decompose under electron-impact conditions according to the Retro-Diels-Alder principle. The pyrolysis of the spiro-dihydrothiopyranes 2 gives the thiophenes 3 and 4. The constitution of the new compounds 2, 3 and 4 finds confirmation from their mass, 1H-and 13C-n.m.r. spectra.
    Notes: Aus Thiofluorenon (1) und 2,3-Dimethyl-bzw. 2,3-Diphenyl-1,3-butadien entstehen die Diels-Alder-Addukte 2a bzw. 2b, die thermisch nicht  -  weder in Lösung noch in Substanz -, wohl aber unter Elektronenstoß nach dem Retro-Diels-Alder-Prinzip zerfallen. Die Pyrolyse der Spiro-dihydrothiopyrane 2 in Substanz liefert die Thiophene 3 und 4. Die Konstitutionsermittlung der neuen Verbindungen 2, 3 und 4 beruht u. a. auf Massen-, 1H-NMR-und 13C-NMR-Spektren.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/cber.19741070916
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Enzymatic Separation of L-Leucine and L-Isoleucine (1983)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1983 (1983), S. 2052-2054 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Enzymatische Trennung von L - Leucin und L,/-IsoleucinDie in ihren chemischen und physikalischen Eigenschaften sehr ähnlichen Aminosäuren L-Leucin und L-Isoleucin können getrennt werden, indem ein Gemisch dieser beiden Substanzen zu einer Mischung aus N-Acetyl-L-leucin und N-Acetyl-L-isoleucin acetyliert wird und diese Mischung bei neutralem pH-Wert einer substratselektiven Hydrolyse unter Einfluß von Nierenacylase unter-worfen wird. Dieses Verfahren erlaubt die Herstellung von hochreinem L-Leucin. Aus der Mutterlauge wird unverändertes N-Acetyl-L-isoleucin in einer Reinheit von 90-93% gewonnen. Hydrolyse mit Salzsäure und fraktionierende Kristallisation als Hydrochloridsalz erlaubt die Herstellung von reinem L-Isoleucin.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198319831124
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Racematspaltung von DL-Cystein (1983)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1983 (1983), S. 2073-2078 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Resolution of DL-CysteineThe diastereomeric 4-thiazolidinecarboxylic acids 3 and 4, obtained by condensation of DL-cysteine (DL-1) with D-(+)-galactose (2), can be separated by crystallization. Ring cleavage of 3 or 4 gives L-cysteine (L-1) or D-cysteine (D-1), respectively. Instead of D-(+)-galactose other chiral aldoses can be employed as resolution agents.
    Notes: Die bei der Kondensation von DL-Cystein (DL-1) mit D-(+)-Galactose (2) entstehenden zueinander diastereomeren 4-Thiazolidincarbonsäuren 3 und 4 lassen sich durch Kristallisation trennen. Bei der Ringspaltung von 3 bzw. 4 entstehen L-Cystein(L-1) bzw. D-Cystein (D-1). Statt D-(+)-Galactose kann man auch andere chirale Aldosen einsetzen.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198319831204
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Optical resolution of racemic S-(Carboxymethyl)cysteine (1982)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1982 (1982), S. 1995-1998 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Racematspaltung von S-(Carboxymethyl)cysteinRacemisches S-(Carboxymethyl)cystein [(R, S)-2] wird in das Ammoniumsalz (R, S)-3 übergeführt, das nach Herstellung einer übersättigten Lösung und Animpfen mit (R)- oder (S)-3 durch fraktionierende Kristallisation gespalten werden kann. (R, S)-2 bildet mit optisch aktiven Aminen diastereomere Salze, die leicht trennbar sind und so ebenfalls eine Racematspaltung erlauben. So erhält man mit (1R,2S)-2-Amino-1-phenyl-1-propanol (4) optisch reines (R)-S-(Carboxymethyl)-cystein [(R)-2] in 93proz. Ausbeute. Die Racematspaltung von (R, S)-2 ist auch mit Hilfe von (R)-1-Phenylethylamin (5) möglich.
    Notes: Racemic S-(carboxymethyl)cysteine [(R, S)-2] obtained from racemic cysteine is resolved via its ammonium salt (R, S)-3 by preferential crystallization procedure. Furthermore, (R, S)-2 forms with optically active amines separable, diastereomeric salts. Thus, (1R,2S)-2-amino-1-phenyl-1-propanol (4) affords optically pure (R)-S-(carboxymethyl)cysteine [(R)-2] in 93% yield. The resolution of (R, S)-2 is also possible with (R)-1-phenylethylamine (5).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198219821108
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Syntheses of 3-Cyanopropan- and 4-Aminobutanamides (1982)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1982 (1982), S. 2098-2102 
    Details
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesen von 3-Cyanpropan- und 4-AminobutanamidenDie 3-Cyanpropanamide 5a - g werden aus Propenamiden und Blausäure oder aus 3-Cyanpropanoylverbindungen nach den Methoden A - D dargestellt. Hydrierung von 5a - d, g liefert die 4-Aminobutanamide 2a - d, g.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.198219821119
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Verwertung industrieller Abfallstoffe, 1. Synthese neuer, chiraler primärer und sekundärer, 1,2-Diamine (1994)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1994 (1994), S. 243-250 
    Details
    ISSN: 0170-2041
    Keywords: 1,2-Diamines ; 2-Azabicyclo[3.3.0]octanes ; Proline analogue ; Cyclopenta[b]pyrroles ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Utilization of Industrial Waste Materials, 1. - Synthesis of New Primary and Secondary Chiral 1,2-DiaminesPrimary and secundary 1,2-diamines with three or four stereogenic centers were synthesized starting from the benzyl ester of the bicyclic proline analogue (all-R)-2-azabicyclo[3.3.0]octane-3-carboxylic acid [(all-R)-2b] by a four- or five-step procedure. This is an example for the utilization of the industrial waste material (all-R)-2b.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.199419940304
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Synthese und Reaktivität von 3-Oxazolinen (1992)
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1992 (1992), S. 1-6 
    Details
    ISSN: 0170-2041
    Keywords: Oxazole, 2,5-dihydro- ; Oxazolidine ; Acyliminium ion ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Reactivity of 3-Oxazolines.3-Oxazolines 1 have been prepared from α-hydroxy aldehydes, ammonia, water and a second oxo compound (aldehyde or ketone) in a one-pot reaction. Carboxylic acid chlorides add to the azomethine bond of 1 to yield 3-acyl-4-chlorooxazolidines 2. 4-Hydroxy and 4-alkoxyoxazolidines 3 are obtained from 2 upon treatment with aqueons sodium hydroxide or alkanol/ triethyl amine, respectively. Some oxazolidines 3 are formed with high diastereoseselectivity.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jlac.199219920102
    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...