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Visar resultat 1 - 5 av 81 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Asymmetric Catalysis : Ligand Design and Conformational Studies

    Författare :Kristina Hallman; KTH; []
    Nyckelord :asymmetric catalysis; chiral ligand; oxazolines; conformational study; allylic substitution; polymer-bound ligands; dendritic ligands; crown ether; oxidations; palladacycle;

    Sammanfattning : This thesis deals with the design of ligands for efficientasymmetric catalysis and studies of the conformation of theligands in the catalytically active complexes. All ligandsdeveloped contain chiral oxazoline heterocycles. LÄS MER

  2. 2. Novel Pincer Complex-Catalyzed Transformations : Including Asymmetric Catalysis

    Författare :Juhanes Aydin; Kálmán J. Szabó; Oleg V. Ozerov; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; pincer; palladium; catalysis; chiral; asymmetric; palladium IV; allylation; aldol; aminoacid; C-H functionalization; cross-coupling; homoallylic; heck reaction; tridentate ligand; Chemistry; Kemi; Organic Chemistry; organisk kemi;

    Sammanfattning : This thesis is focused on the development of new pincer complex-catalyzed transformations. Optimization of the catalytic properties (fine-tuning) was directed to increase the catalytic activity as well as the chemo-, stereo- and enantioselectivity of the complexes. LÄS MER

  3. 3. Asymmetric catalysis : ligand design and microwave acceleration

    Författare :Ulf Bremberg; KTH; []
    Nyckelord :;

    Sammanfattning : This thesis deals partly with the design and synthesis ofligands for use in asymmetric catalysis, and partly with theapplication of microwave heating on metal-based asymmetriccatalytic reactions.Enantiomerically pure pyridyl alcohols and bipyridylalcohols were synthesized from the chiral pool for future usein asymmetric catalysis. LÄS MER

  4. 4. Surface Studies of Model Systems relevant for Pd and Ag Catalysts

    Författare :Natalia Martin; Synkrotronljusfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; High Pressure X-ray Photoelectron Spectroscopy; X-ray Photoelectron Spectroscopy; alumina; Ag; NiAl; Pd; catalysis; model system; Surface X-ray Diffraction; Low Energy Electron Diffraction; Scanning Tunneling Microscopy; Fysicumarkivet A:2014:Martin;

    Sammanfattning : This PhD thesis reports on investigations of the atomic scale structure of model catalysts relevant for the catalytic oxidation of CO and methane over Pd, and NOx reduction over silver-alumina, important reactions in automotive catalysts. By using complementary experimental techniques such as X-ray Photoelectron Spectroscopy, High Pressure X-ray Photoelectron Spectroscopy, Surface X-ray Diffraction, Low Energy Electron Diffraction, Infrared Spectroscopy, and Scanning Tunneling Microscopy, combined with theoretical calculations, the work presented in this thesis aims at an atomistic characterization of the active sites for silver-alumina and Pd model catalysts which may help to the design of new and improved catalysts. LÄS MER

  5. 5. Surface structure and catalytic activity of Pd and Fe oxide surfaces and thin films

    Författare :Mikhail Shipilin; Synkrotronljusfysik; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Surface X-ray diffraction SXRD ; Heterogeneous catalysis; Pd; PdO; Fe; FeO; Thin films; Fysicumarkivet A:2016:Shipilin;

    Sammanfattning : The present work is devoted to atomic scale structural studies of the surfaces of model heterogeneous catalysts relevant to oxidation reactions. A novel approach using high-energy surface X-ray diffraction combined with mass-spectrometry measurements is employed to perform in situ structural characterization of Pd(100) and Pd(553) single crystal surfaces acting as catalysts in the process of CO oxidation under semirealistic conditions. LÄS MER