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  • 1
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    Unknown
    Wiesbaden : Periodicals Archive Online (PAO)
    Geographische Zeitschrift. 35:4/5 (1929) 193 
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 1980 (1980), S. 600-610 
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Syntheses with α-Metalated Isocyanides, XLV1).  -  Reactions of α-Metalated Isocyanides with Some 1,3-DipolesReaction of α-metalated isocyanides 1a - c, f with alkylideneamine oxides (nitrones) 4 affords the 2-imidazolidinones 8. The 6-metalated 2,3-dihydro-4-H-1,2,5-oxadiazine of type 5 is postulated as decisive intermediate.  -  Benzonitrile oxide (17) reacts analogously with 1a and 1b to give 4-imidazolin-2-ones 18 and with 1e to give the 3-imidazolin-2-one 19.  -  Phenyl azide (20) reacts with two moles of 1b to give 5-(benzylideneamino)-4H,5H-1,2,3-triazoline 24. The reaction course is discussed.
    Notes: Die α-metallierten Isocyanide 1a - c, f reagieren mit den Alkylidenaminoxiden (Nitronen) 4 zu 2-Imidazolidinonen des Typs 8. Als entscheidende Zwischenstufe wird ein 6-metalliertes 2,3-Dihydro-4H-1,2,5-oxadiazin vom Typ 5 postuliert.  -  Benzonitriloxid (17) ergibt mit 1a und 1b analog die 4-Imidazolin-2-one 18, mit 1e das 3-Imidazolin-2-on 19.  -  Phenylazid (20) setzt sich mit zwei Äquivalenten 1b zum 5-Benzylidenamino-4H,5H-1,2,3-triazolin 24 um. Der Reaktions-verlauf wird diskutiert.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 3
    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, XXVIII1).  -  Oxazoles Unsubstituted in Position 2 from α-Metalated Isocyanides and Acylating ReagentsThe oxazoles 6 unsubstituted in position 2 (see table 1) are obtained from the α-metalated isocyanides 2 and acylating reagents such as the acid chlorides 3, the ethyl carboxylates 4 or the amides 5. Intermediates are the β-ketoisocyanides 7 which cyclize either in situ or during workup.  -  From potassium ethyl isocyanopropionate (12) and enolisable acyl chlorides the 5-alkylidene-4-methyloxazoline-4-carboxylates 15 are formed.  -  Reaction of potassium ethyl isocyanoacetate (2a, M =K) with 0.5 equivalents ethyl chloroformate affords the potassium diethyl isocyanomalonate (8, R1 = CO2C2H5, R2 = OC2H5) which can be alkylated in situ by alkyl halides to the diethyl α-alkyl-α-isocyanomalonates 16, the precursors of higher amino acids.
    Notes: Die in 2-Stellung unsubstituierten Oxazole 6 (vgl. Tabelle 1) erhält man aus den α-metallierten Isocyaniden 2 und Acylierungsmitteln wie den Säurechloriden 3, den Carbonsäureestern 4 oder den Carbonsäureamiden 5. Zwischenstufen sind die β-Ketoisocyanide 7, die entweder in situ oder beim Aufarbeiten cyclisieren.  -  Aus Kalium-2-isocyanpropionsäure-äthylester (12) und enolisierbaren Carbonsäurechloriden entstehen die 5-Alkyliden-4-methyloxazolin-4-carbonsäure-äthylester 15.  -  Aus Kalium-isocyanessigsäure-äthylester (2a, M = K) und 0.5 Äquivalenten Chlorameisensäure-äthylester erhält man Kalium-isocyanmalonsäure-diäthylester (8, R1 = CO2C2H5, R2 = OC2H5), der in situ mit Alkylhalogeniden zu den α-Alkyl-α-isocyanmalonsäure-diäthylestern 16 umzusetzen ist, den Vorstufen für höhere Aminosäuren.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 4
    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, XVII1).- N-(1-Arylsulfonyl-1-alkenyl) formamides from α-Metalated Arylsulfonylmethyl Isocyanides and Carbonyl Compounds, Conversion of a Carbonyl Compound into the Next Higher Carboxylic AcidN-(1-Arylsulfonyl-1-alkenyl)formamides 10 and 11 are obtained by reaction of potassium arylsulfonylisocyanomethanides 5 with carbonyl compounds (formylaminomethylenation). Hydrolysis of the formamides 10 or 11 yields the carboxyclic acids 16, which contain one more carbon atom. - Reaction of 4-methylphenylsulfonylmethyl isocyanide (4a) with carbonyl compounds 1 in weakly basic ethanolic medium gives 4-(4-methylphenylsulfonyl)-2-oxazolines 12, which on treatment with potassium tert.-butoxide are transformed into the formamides 10.
    Notes: N-(1-Arylsulfonyl-1-alkenyl)-formamide 10 und 11 erhält man durch Umsetzung von Kalium-arylsulfonyl-isocyanmethaniden 5 und Carbonylverbindungen in Tetrahydrofuran (Formylaminomethylenierung). Die Hydrolyse der Produkte liefert die Carbonsäuren 16, die ein Kohlenstoffatom mehr enthalten. - Die Umsetzung von 4-Methylphenylsulfonyl-methylisocyanid (4a) mit Carbonylverbindungen 1 in schwach basischem äthanolischem Medium ergibt 4-(4-Methylphenylsulfonyl)-2-oxazoline 12, die mit Kalium-tert.-butanolat in Tetrahydrofuran in die Formamide 10 umwandelbar sind.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
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  • 5
    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, XXXI.  -  2-Oxazolines from α-Metalated Isocyanides and Carbonyl Compounds. A New Synthesis of β-Amino Alcoholsα-Metalated isocyanides 2, prepared from isocyanides 1 and bases such as butyllithium, potassium tert-butoxide or lithium tetramethylpiperidide in tetrahydrofuran react at ca.  -  70°C with carbonyl compounds 3 to give the adducts 4, which are in equilibrium with the 2-metalated 2-oxazolines 5. Addition of methanol prior to workup yields 2-oxazolines 6. Possible side reactions are discussed. Since 2-oxazolines 6 are readily hydrolysed the reaction represents a new route to β-amino alcohols.  -  2-Oxazolines 6 react with butyllithium preferably in position 2. The 2-lithiated oxazolines 5 (M = Li) are tautomeric with the open-chain compounds 4. Depending on the electrophile, trapping experiments afford derivatives of either 4 or 5 in kinetically or thermodynamically controlled reactions.
    Notes: α-Metallierte Isocyanide 2, dargestellt aus Isocyaniden 1 und Basen wie Butyllithium, Kalium-tert-butylat oder Lithium-tetramethylpiperidid reagieren bei ca.  -  70°C mit Carbonylverbindungen 3 zu den Addukten 4, die (reversibel) zu 2-metallierten 2-Oxazolinen 5 cyclisieren. Nach Zugabe von Methanol lassen sich diese in Form von 2-Oxazolinen 6 isolieren. Mögliche Nebenreaktionen werden diskutiert. Da die 2-Oxazoline 6 leicht hydrolysierbar sind, eröffnet sich so auch ein ergiebiger Zugang zu den β-Aminoalkoholen 8.  -  Die 2-Oxazoline 6 werden durch Butyllithium bevorzugt in 2-Position metalliert, wobei wiederum die Verbindungen 5 (M = Li) resultieren, die in Tautomerie mit den offenkettigen Alkoholaten 4 stehen. Bei Abfangversuchen erhält man je nach Elektrophil in kinetisch oder thermodynamisch kontrollierter Reaktion Derivate von 4 oder von 5.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 6
    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, XXXV. - 5-(Methylthio)thiazoles from u-Metalated Isocyanides and Carbon Disulfideα-Metalated isocyanides 2a- c react with carbon disulfide to give the intermediates 5 which on methylation yield 5-(methylthio)thiazoles 6.
    Notes: Die Umsetzung von α-metallierten Isocyaniden 2a- c mit Schwefelkohlenstoff und anschließenden Methylierung der Zwischenstufen 5 liefert 5-(Methylthio)thiazole 6.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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