Sökning: "epoxide rearrangement"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden epoxide rearrangement.

  1. 1. Development of New Chiral Bicyclic Ligands : Applications in Catalytic Asymmetric Transfer Hydrogenation, Epoxidations, and Epoxide Rearrangements

    Författare :Arnaud Gayet; Andersson Pher G.; Hilmersson Göran; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic chemistry; asymmetric catalysis; transfer hydrogenation; epoxide rearrangement; Organocatalysed epoxidation; chiral ligand; allylic alcohol; kinetic resolution; lithium amide; Organisk kemi; Organic chemistry; Organisk kemi;

    Sammanfattning : This thesis describes the synthesis and application of new chiral bicyclic ligands and their application in asymmetric catalysis. The studies involved: [i] The development of novel chiral bicyclic amino sulfur ligands and their use in transfer hydrogenation. LÄS MER

  3. 2. Synthesis and Rearrangement of Epoxy Sugars

    Författare :Fritiof Pontén; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organisk kemi; Organic chemistry; crown ether; silica; Intramoleculaf Diels-Alder reaction; radical allylation; allyl sulfone; sugar epoxide; allyl sulfide; ring-contraction; C-glycoside; a; IMDAF; b-unsaturated aldehyde;

    Sammanfattning : Ring-Contraction of sugar-derived epoxy alcohols, functionalised in position 1 and 6, by treatment with lithium bromide and N, N, N', N'-tetramethylurea in refluxing toluene gave enantiomerically pure a,b-unsaturated aldehydes of furanosides. O-Glycosidic epoxy alcohols gave only one, easily purified, aldehyde in approximately 30-60% yield depending on the substitution pattern. LÄS MER

  4. 3. Asymmetric Formation and Isomerization of Three-Membered Rings : Catalyst Development and Evaluation

    Författare :Sophie Bertilsson; Tobias Rein; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry; allylic alcohol; α-amino acid derivative; aza-Diels-Alder reaction; aziridination; cyclopropanation; desymmetrization; epoxide rearrangement; kinetic resolution; lithium amide; rhodium-carboxylate; Kemi; Chemistry; Kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : Enantiopure α-amino acid derivatives were prepared using a protocol which allows for highly controlled regio- and chemoselectivity in the hydrogenation/ hydrogenolysis of aza-Diels-Alder adducts. One of the resulting α-amino esters, (1S,3R,4R)-2-azabicyclo[2.2.1]heptane-3-carboxylic acid ethyl ester, was utilized further as a catalyst precursor. LÄS MER

  5. 4. Allylic alcohols and aziridines from alkenes : Studies in asymmetric catalysis

    Författare :Mikael J. Södergren; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry; Enantioselective; allylic alcohols; epoxide rearrangement; lithium amides; desymmetrization; kinetic resolution; allylic oxidation; alkenes; aziridination; Kemi; Chemistry; Kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : The development of methodology for asymmetric catalytic transformation of alkenederivatives is summarized. The studies concern the [a] Cu(I)-catalyzed allylic oxidation,[b] isomerization of epoxides to allyl alcohols, and [c] Cu(I)-catalyzed alkeneaziridination, respectively.[a] The preparation of exo-2-azabicyclo[2.2. LÄS MER

  7. 5. New synthetic routes to azaspiro alkaloids : Applications to the synthesis perhydrohistrionicotoxin

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

    Sammanfattning : Perhydrohistrionicotoxin, 1, is related to a family of alkaloids which display pharmacologically interesting properties. The thesis deals with development of new methods for the chemical synthesis of such alkaloids, and is divided into three parts according to the different approaches. LÄS MER