Search for dissertations about: "racemization"

Showing result 1 - 5 of 34 swedish dissertations containing the word racemization.

2. 1. 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

4. 2. Heterogeneous catalysis in racemization and kinetic resolution along a journey in protein engineering

   Author : Tamás Görbe; Jan-Erling Bäckvall; Frank Hollmann; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; racemization; protein engineering; kinetic resolution; heterogeneous catalysis; biohybrid catalyst; organisk kemi; Organic Chemistry;

   Abstract : The first part of my thesis concerns the use of heterogeneous acidic resins for racemization of tert-alcohols without any side-product formation. The focus was to develop a system which can be further extended to a DKR protocol consisting of an enzymatic KR reaction. READ MORE

5. 3. Studies on Metalloenzymatic Dynamic Kinetic Resolutions and Iron-Catalyzed Reactions of Allenes

   Author : Karl P. J. Gustafson; Jan-Erling Bäckvall; Johannes de Vries; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Racemization; Dynamic Kinetic Resolution; Enzyme Catalysis; XAS; Asymmetric Synthesis; organisk kemi; Organic Chemistry;

   Abstract : The main focus of this thesis lies in the development of new transition metal-catalyzed chemoenzymatic dynamic kinetic resolutions (DKR) of both alcohols and amines. The first part of the thesis deals with the development of new heterogeneous systems for the DKR of amines. READ MORE

6. 4. Studies of Biomimtic Oxidations and Racemizations

   Author : Gábor Csjernyik; Jan-Erling Bäckvall; Serafino Gladiali; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; oxidation of alcohols; ruthenium; porphyrin; racemization;

   Abstract : This thesis deals with studies of ruthenium-catalyzed hydrogen transfer reactions for oxidations and racemization.Through optimisation of the substrate-selective redox catalyst, the electron and proton transfer mediator (a benzoquinone derivative), and the oxygen-activating metal macrocycle a highly efficient biomimetic oxidation of secondary alcohols was obtained. READ MORE

7. 5. Ruthenium-Catalyzed Hydrogen Transfer Reactions : Mechanistic Studies and Chemoenzymatic Dynamic Kinetic Resolutions

   Author : Madeleine Warner; Jan-Erling Bäckvall; Andreas Pfaltz; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Hydrogen transfer; ruthenium catalysis; kinetic resolution; dynamic kinetic resolution; racemization; asymmetric synthesis; organisk kemi; Organic Chemistry;

   Abstract : The main focus of this thesis lies on transition metal-catalyzed hydrogen transfer reactions. In the first part of the thesis, the mechanism for racemization of sec-alcohols with a ruthenium complex, Ru(CO)2Cl(η5-C5Ph5) was studied. READ MORE