Sökning: "aromatic substitution reaction"

Visar resultat 16 - 20 av 26 avhandlingar innehållade orden aromatic substitution reaction.

  1. 16. Proton-Conducting Sulfonated and Phosphonated Polymers and Fuel Cell Membranes by Chemical Modification of Polysulfones

    Författare :Benoit Lafitte; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Macromolecular chemistry; Makromolekylär kemi; Material technology; Materiallära; materialteknik; chemical modification; lithiation; fuel cells; polyelectrolyte; sulfonated polymers; proton-conducting polymer membranes polysulfone; phosphonated polymers;

    Sammanfattning : The proton exchange membrane fuel cell (PEMFC) is currently emerging as an efficient and environmentally friendly power source. The technology is very complex and relies ultimately on materials and components which need further development. LÄS MER

  3. 17. Synthesis of new building blocks for conjugated oligomers

    Författare :Fredrik Allared; KTH; []
    Nyckelord :organic semiconductors; thiophenes; heterocyclic synthesis; dithienothiophene; naphthalene;

    Sammanfattning : This thesis deals with the synthesis of new organicmaterials for electronic applications. Several new ring-formingmethods are employed to construct sulphur heterocycles: Tandemelectrophilic aromatic substitution and acid-catalyzedtransetherification of methoxythiophene, double electrophilicaromatic substitutions with ethane-1, 2-disulphenyl chloride,and also, the reaction of dienes with sulphur dichloride. LÄS MER

  4. 18. Bispidine derivatives as molecular tools for studies of (-Allyl)palladium complexes : Ligand synthesis and analythical cpplications

    Författare :Andreas Axén; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry; Kemi; Chemistry; Kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : Determination of structural and stereochemical features of reaction intermediates in transition metal catalysed reactions is of central interest. Bispidine derivatives as ligands in (π-allyl)palladium complexes in combination with 1H NMR spectroscopy are shown to be useful tools for revealing structural characteristics of these reaction intermediates. LÄS MER

  5. 19. Enantioenriched Cyanohydrins and Acetoxyphosphonates – Synthesis and Applications

    Författare :Robin Hertzberg; Christina Moberg; Frank Glorius; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asymmetric synthesis; cyanohydrins; acetoxyphosphonates; biocatalyst; titanium catalyst; minor enantiomer recycling; cross-coupling; amino alcohols; Kemi; Chemistry;

    Sammanfattning : In this thesis, the synthesis of enantioenriched compounds using novel methodologies that employ metal- and biocatalysis is described.In the first part, the synthesis of enantioenriched cyanohydrins, which are highly versatile synthetic intermediates, is described. LÄS MER

  7. 20. Redesign of substrate specificity of glutathione transferase and glutathione reductase : Enzyme engineering by directed mutagenesis, phage-display selection and DNA shuffling

    Författare :Lars O. Hansson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biochemistry; Biokemi; Biochemistry; Biokemi; biokemi; Biochemistry;

    Sammanfattning : Human glutathione transferase (GST) A1-1 was expressed in fusion with the phage gene IIIproduct and a library of phage-displayed GST mutants was constructed by randomization of fouractive-site residues. Variant GSTs were isolated by mechanism-based phage display selection, using an immobilized transition-state analog of a nucleophilic aromatic substitution (SNAr) reaction. LÄS MER