Sökning: "aziridines"

Visar resultat 1 - 5 av 21 avhandlingar innehållade ordet aziridines.

  1. 1. Lewis acid Mediated Aza-Diels-Alder Reactions and Asymmetric Alkylations of 2H-azirines

    Författare :Erik Risberg; KTH; []
    Nyckelord :Enantioselective; diastereoselective; vinyl azide; 2H-azirines; aziridines; Lewis acid; chiral ligand; chiral auxiliary organolithiums Diels-Alder reaction alkyl radicals triethylborane.;

    Sammanfattning : This thesis describes the use of 2H-azirines, three-membered unsaturatednitrogen-containing heterocycles, as reactive intermediates ina number of Lewis acid promoted alkylations and Diels-Alderreactions providing synthetically useful aziridines. In order to carry out this investigation a new generalprocedure for the ring closure of vinyl azides, forming theresultant 3-substituted-2H-azirines, was developed applying low boiling solventsin closed reaction vessels at elevated temperatures. LÄS MER

  2. 2. Development of Catalytic Enantioselective Approaches for the Synthesis of Carbocycles and Heterocycles

    Författare :Luca Deiana; Armando Córdova; Andrei Malkov; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Organocatalysis; Asymmetric Catalysis; Heterogeneous Catalysis; Aziridines; Pyrazolidines; Cyclopentanes; Organic Chemistry; organisk kemi;

    Sammanfattning : In biological systems, most of the active organic molecules are chiral. Some of the main constituents of living organisms are amino acids and sugars. They exist predominantly in only one enantiomerically pure form. LÄS MER

  3. 3. Asymmetric synthesis via C2-symmetric aziridines

    Författare :Carin Birgersson; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP;

    Sammanfattning : .... LÄS MER

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

    Författare :Mikael J. Södergren; Uppsala universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; 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

  5. 5. C2- and C3-symmetric ligands via ring-opening of aziridines

    Författare :Fredrik Lake; KTH; []
    Nyckelord :asymmetric catalysis; aziridine; benzaldehyde; diethylzinc; enantionselective; ligand; proazaphosphatrane; ring-opening; sulfonamide; symmetry; titanium; nicronium;

    Sammanfattning : This thesis deals with the design and synthesis of chiralenantiopure nitrogencontaining ligands and the use of theseligands in asymmetric catalysis. A modular synthetic approachto enantiopure nitrogen-containing ligands was developed. Thesynthetic method is based on the ring-opening of activatedchiral aziridines by nitrogen nucleophiles. LÄS MER