Sökning: "asymmetric"
Visar resultat 6 - 10 av 702 avhandlingar innehållade ordet asymmetric.
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
Sammanfattning : 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. LÄS MER
7. Absolute Asymmetric Synthesis
Sammanfattning : 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. LÄS MER
8. Asymmetric transformation of ß- and γ-functionalized alcohols : Study of combined ruthenium-catalyzed racemization and enzymatic resolution
Sammanfattning : 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. LÄS MER
9. Asymmetric Cellular Microenvironments
Sammanfattning : 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. LÄS MER
10. Asymmetric [2,3]-Sigmatropic Rearrangement of Allylic Ammonium Ylides
Sammanfattning : 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. LÄS MER