Search for dissertations about: "asymmetric"

Showing result 6 - 10 of 677 swedish dissertations containing the word asymmetric.

  2. 6. Synthesis and Evaluation of N,P-Chelating Ligands in Asymmetric Transition-Metal-Catalyzed Reactions : Ir-Catalyzed Asymmetric Hydrogenation and Pd-Catalyzed Asymmetric Intermolecular Heck Reaction

    Author : Päivi Tolstoy; Pher G. Andersson; Göran Hilmersson; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Asymmetric hydrogenation; Heck reaction; N; P ligand; Iridium; Palladium; Asymmetric catalysis; Alkenes; Fluorine; Diarylmethine stereocenters; Chemistry; Kemi; organisk kemi; Organic Chemistry;

    Abstract : This thesis describes synthesis of new chiral N,P ligands and their evaluation in two types of asymmetric transition-metal catalyzed reactions. The first part of the thesis describes studies in iridium-catalyzed asymmetric hydrogenation. READ MORE

  4. 7. Absolute Asymmetric Synthesis

    Author : Anders Lennartson; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; absolute asymmetric synthesis; enantioselective synthesis; chirality; optical resolution; spontaneous resolution; conglomerate; organozinc reagents; organometallic chemistry; coordination chemistry; supramolecular chemistry; intermolecular interactions; optical resolution;

    Abstract : Absolute asymmetric synthesis is the synthesis of optically active products from achiral or racemic precursors only. This has generally been regarded as impossible and is relevant in the discussion of the origins of biomolecular homochirality. READ MORE

  5. 8. Asymmetric transformation of ß- and γ-functionalized alcohols : Study of combined ruthenium-catalyzed racemization and enzymatic resolution

    Author : Annika Träff; Jan-Erling Bäckvall; Reko Leino; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Kinetic resolution; dynamic kinetic resolution; kinetic asymmetric transformation; dynamic kinetic asymmetric transformation; enzyme catalysis; racemization; asymmetric synthesis; chlorohydrin; cyano acetate; amino alcohol; metalloenzyme; bifunctional catalytic system; Organic synthesis; Organisk syntes; organisk kemi; Organic Chemistry;

    Abstract : The major part of this thesis describes the asymmetric synthesis of β- and γ-amino alcohols through the combination of ruthenium catalyzed racemization and enzymatic kinetic resolution. The dynamic kinetic resolution, DKR, protocol for chlorohydrins was improved by employing Bäckvall’s catalyst, which is a base activated racemization catalyst, in combination with Burkholderia cepacia lipase. READ MORE

  6. 9. Asymmetric Cellular Microenvironments

    Author : Susanna Rydholm; Hjalmar Brismar; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physics; Fysik;

    Abstract : This thesis presents methods to combine 3D cell culture, microfluidics and gradients on a controlled cellular scale. 3D cultures in biological extracellular matrix gels or synthetic gels bridge the gap between organ-tissue cultures and traditional 2D cultures. READ MORE

  7. 10. Asymmetric [2,3]-Sigmatropic Rearrangement of Allylic Ammonium Ylides

    Author : Jan Blid; Peter Somfai; James C. Anderson; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; asymmetric; [2; 3]-sigmatropic rearrangement; allylic amine; ammonium ylide; Lewis acid; enantioselective; boron; phosphazene base; NMR spectroscopy; DFT-calculations; Organic chemistry; Organisk kemi;

    Abstract : The thesis describes the realization of an asymmetric [2,3]-sigmatropic rearrangement of achiral allylic amines. It is divided into two parts; the first part deals with the development of a Lewis acid-mediated [2,3]-sigmatropic rearrangement and the second the asymmetric version thereof. READ MORE