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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Liebigs Annalen 736 (1970), S. 141-144 
    ISSN: 0075-4617
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Reaction of Diphenylmethane to Anthracene in Anhydrous Hydrogen Fluoride/Boron TrifluorideIn anhydrous hydrogen fluoride/boron trifluoride diphenylmethane (1) forms anthracene (8), benzene and higher benzylated products. In an excess of benzene the formation of these hydrocarbons is reduced. A reaction mechanism is proposed.
    Notes: Die Reaktion von Diphenylmethan (1) reagiert in wasserfreiem Fluorwasserstoff/Bortrifluorid zu Anthracen (8), Benzol und höher benzylierten Produkten. In Gegenwart größerer Mengen Benzol wird die Bildung dieser Kohlenwasserstoffe zurückgedrängt. Ein Reaktionsmechanismus wird vorgeschlagen.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für die chemische Industrie 106 (1994), S. 2473-2506 
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Die von Richard F. Heck Ende der sechziger Jahre entdeckte Palladium-katalysierte Kupplung von Aryl- und Alkenylhalogeniden mit Alkenen hat sich nach gelegentlichem Auf- und Abschwellen des darauf gerichteten Interesses in den letzten sechs Jahren nachhaltig gemausert. Durch geschickte Auswahl der Substrate und sorgfältige Anpassung der Reaktionsbedingungen gelingen beeindruckende Sequenzen auch unterschiedlicher Reaktionstypen nicht nur nacheinander, sondern vielfach in einem einzigen Verfahrensschritt. Die mittlerweile etablierte Heck-Reaktion - und eine Reihe mit ihr mechanistisch verwandter Palladium-katalysierter Umwandlungen an Aren-, Alken- und Alkinderivaten - bietet ungezählte Möglichkeiten, elegant und hochkonvergent komplexe Moleküle aufzubauen; dabei bereiten Sauerstoff- und Stickstoffatome (mit Einschränkungen auch Schwefel- und Phosphoratome) in den Reaktionen keine Probleme. Das Spektrum der neueren Erfolge beginnt mit den chemo- und regioselektiven Einfachkupplungen hochfunktionalisierter Substrate mit unsymmetrisch mehrfach substituierten Reaktionspartnern. Es reicht allerdings viel weiter über Kaskadenreaktionen mit Knüpfung von drei, vier, fünf oder gar acht neuen C—C-Bindungen unter Bildung von oligofunktionellen und oligocyclischen Produkten von beeindruckender Molekülkomplexität bis hin zum enantioselektiven Aufbau von anspruchsvollen Naturstoffmolekülen mit quartären stereogenen Zentren, wie die Beispiele Crinan, Picrotoxinin, Morphin und viele mehr belegen. Zweifellos läßt sich schon heute die Heck-Reaktion aus dem Methodenarsenal der präparativen Organischen Chemie nicht mehr wegdenken; abzuwarten bleibt lediglich, wann sie Einzug in ein industrielles Produktionsverfahren halten wird.
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  • 3
    Electronic Resource
    Electronic Resource
    Chichester [u.a.] : Wiley-Blackwell
    Developmental Genetics 13 (1992), S. 16-25 
    ISSN: 0192-253X
    Keywords: Nucleotide sequence of macronuclear chromosome ; multiple introns ; ciliate pheromone ; UGA codon translation ; leader peptide ; Life and Medical Sciences ; Genetics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: We have cloned and sequenced a 1.7 kb macronuclear chromosome encoding the pheromone 4 gene of Euplotes octocarinatus. The sequence of the secreted pheromone is preceded by a 42 amino acid leader peptide, which ends with a lysine residue. The sequence coding for the leader peptide contains information for a putative signal peptide and is interrupted by a 772 bp intron as shown by comparison with a cDNA clone. A 64 bp intron and a 145 bp intron interrupt the sequence coding for the secreted pheromone. The three introns contain typical 5′ and 3′ splice junctions and a putative branch point site. The small introns have a low GC content. The large intron has a GC content similar to that of the pheromone 4 gene exons. The amino acid sequence of pheromone 4, deduced from both the genomic DNA and the cDNA of pheromone 4, shows that the secreted pheromone consists of 85 amino acids. One of its amino acids is encoded by a UGA codon. Since it has been shown for pheromone 3 of E. octocarinatus that UGA is translated as cysteine, it is assumed that the UGA codon encodes cysteine in pheromone 4 as well. The 164 bp noncoding region upstream of the leader peptide is AT-rich and contains an inverted repeat capable of forming a stem-loop structure with a stem of 11 bp. The 151 bp noncoding region at the 3′ end of the chromosome contains a putative polyadenylation sequence and an inverted repeat. The macro-nuclear molecule is flanked by telomeres and carries the pentanucleotide motif TTGAA, located at a distance of 17 nucleotides from the telomeres. This motif has been suggested to be involved in the formation of macronuclear chromosomes. © 1992 Wiley-Liss, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 33 (1995), S. 2379-2411 
    ISSN: 0570-0833
    Keywords: C-C coupling ; Synthetic methods ; Heck reaction ; Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The palladium-catalyzed coupling of haloarenes and haloalkenes with alkenes, which was discovered by Richard F. Heck in the late sixties, has been a topic of fluctuating interest; however, in the last six years activity in this area has flourished. Careful choice of substrates and skillful tailoring of reaction conditions lead to impressive sequences consisting of even different reaction types that occur not only in a consecutive mode, but also in a single operation. The wellestablished Heck reaction, together with other mechanistically related palladiumcatalyzed transformations with arene, alkene, and alkyne derivatives, opens the door to a tremendous variety of elegant and highly convergent routes to structurally complex molecules. The reaction is not disturbed by heteroatoms such as oxygen and nitrogen (nor by sulfur and phosphorus with some limitations). The spectrum of recent achievements starts with a range of chemoselective and regioselective monocouplings of highly functionalized substrates with unsymmetrical and multisubstituted reaction partners. Other advances include cascade reactions in which three, four, five, and even eight new C—C bonds are formed to yield oligofunctional and oligocyclic products with impressive molecular complexity. Even the enantioselective construction of complex natural products with quaternary stereocenters has been achieved with Heck reactions in key steps, as exemplified by the synthesis of crinan, picrotoxinin, and morphine. Today, the Heck reaction is indispensible in the arsenal of synthetic methods available to organic chemists. Certainly it is only a matter of time before the Heck reaction is applied in industrial syntheses.
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  • 5
    Publication Date: 2015-01-30
    Description: Journal of the American Chemical Society DOI: 10.1021/ja512232f
    Print ISSN: 0002-7863
    Electronic ISSN: 1520-5126
    Topics: Chemistry and Pharmacology
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