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Visar resultat 16 - 20 av 91 avhandlingar som matchar ovanstående sökkriterier.
16. 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
17. Synthesis and asymmetric transformations of diols by enzyme- and ruthenium catalysis
Sammanfattning : The major part of this thesis describes the synthesis of aliphatic secondary diols and the development of lipase- and ruthenium-catalyzed asymmetric transformations of these diols. Several acyclic 1,4-diols and 1,5-diols were synthesized, and by combining a lipase-catalyzed asymmetric transformation with a ruthenium-catalyzed epimerization, enantiomerically- and diastereomerically enriched diacetates were obtained. LÄS MER
18. Flexibility – a tool for chirality control in asymmetric catalysis
Sammanfattning : This thesis deals with the design and synthesis of ligands for asymmetric catalysis: palladium catalyzed allylic alkylations, and rho-dium and iridium catalyzed hydrogenations of olefins. Chirally flexible phosphepine ligands based on biphenyl were synthesized and their properties were studied. LÄS MER
19. Symmetry in Asymmetric Catalysis and Hydrogen Bond-Based Self-Assembly : Synthesis and Investigations
Sammanfattning : The thesis elaborates on four different projects focusing on synthesizing symmetry-related molecules and investigating their performance as catalysts for asymmetric catalysis or as monomers for hydrogen bond-based self-assembly.Chapter 2 describes a new method to desymmetrize a meso-ligand. LÄS MER
20. Development of organocatalytic asymmetric transformations
Sammanfattning : The ability of amino acids and amino acid derivatives to mediate various organocatalytic asymmetric transformations has been investigated and applied in the development of various reactions. This work describes the development of a direct catalytic asymmetric α-aminomethylation of ketones and aldehydes, a catalytic asymmetric aziridination, hydrophosphination and amination of α,β-unsaturated aldehydes. LÄS MER
