Sökning: "dynamic transformations"

Visar resultat 1 - 5 av 54 avhandlingar innehållade orden dynamic transformations.

  1. 1. Dynamic Systems : Enzymatic Synthesis, Exchange Reactions and Applications in Materials Science

    Författare :Yang Zhang; Olof Ramström; Mihail D. Barboiu; KTH; []
    Nyckelord :constitutional dynamic chemistry; reversible reactions; kinetic resolution; dynamic kinetic resolution; enzyme catalysis; lipase; asymmetric synthesis; racemization; oxazolidinone; organogel; enamine; nitroaldol reaction.;

    Sammanfattning : This thesis is divided into three parts, revolving around the developments of dynamic systems utilized in dynamic kinetic resolution (DKR) and constitutional dynamic chemistry (CDC).The first section gives an introduction to constitutional dynamics, the core concept of this thesis. LÄS MER

  2. 2. Chemoenzymatic Resolution in Dynamic Systems : Screening, Classification and Asymmetric Synthesis

    Författare :Yan Zhang; Olof Ramström; Sabine Flitsch; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; constitutional dynamic chemistry; dynamic systemic resolution; dynamic kinetic resolution; enzyme catalysis; transesterification; enzyme promiscuity; asymmetric synthesis; pattern recognition; self-inhibition.;

    Sammanfattning : This  thesis  is  divided  into  four  parts,  all  centered  around  Constitutional Dynamic  Chemistry  (CDC)  and  Dynamic  Kinetic  Resolution  (DKR)  using biocatalysts for selective transformations, and their applications in screening of bioactive compounds, organic synthesis, and enzyme classification.   In  part  one,  an  introduction  to  CDC  and  DKR  is  presented,  illustrating  the basic  concepts,  practical  considerations  and  potential  applications  of  such dynamic systems, thus providing the background information for the studies in the following chapters. LÄS MER

  3. 3. Multiscale modeling of dynamic recrystallization

    Författare :Ylva Mellbin; Hållfasthetslära; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dynamic recrystallization; Crystal plasticity; Texture; Grain size strengthening; Vertex model; Nucleation; Particle pinning; Large deformations; Multiscale modeling; GPGPU;

    Sammanfattning : During thermomechanical processing of metals, changes occur in the microstructure of the material which affect its macroscopic properties. By understanding these transformations in the microstructure, it becomes possible to design the processes in a way which yields the desired properties in the finished product. LÄS MER

  4. 4. Synthetic Transformations via Metal- and Enzyme-Catalyzed Dynamic Kinetic Resolution

    Författare :Krisztián Bogár; Jan-Erling Bäckvall; Romas Kazlauskas; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ruthenium; racemization; lipase; dynamic kinetic resolution; secondary alcohol; Candida antarctica lipase B; Organic chemistry; Organisk kemi; Organic Chemistry; organisk kemi;

    Sammanfattning : This thesis deals with the preparation of a new half-sandwich type ruthenium(II)- catalyst for racemization of optically active secondary alcohols and the development of a highly efficient method in combination with lipases such as Candida antarctica lipase B and Pseudomonas cepacia lipase for dynamic kinetic resolution of various functionalized alcohols under mild reaction conditions.It was shown that the RuCl(CO)2(η5-C5Ph5) complex can racemize optically active aliphatic and aromatic secondary alcohols at room temperature in rather short times. LÄS MER

  5. 5. Development of catalytic enantioselective C-C bond-forming and cascade transformations by merging homogeneous or heterogeneous transition metal catalysis with asymmetric aminocatalysis

    Författare :Samson Afewerki; Armando Córdova; MICHELANGELO GRUTTADAURIA; Mittuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asymmetric catalysis; transition metals; aldehydes; heterogeneous catalysis; amino acid; organocatalysis; α-allylation; β-alkylation; dynamic transformations; polysubstituted; carbocycles; spirocyclic oxindoles; all-carbon quaternary stereocenters;

    Sammanfattning : Chiral molecules play a central role in our daily life and in nature, for instance the different enantiomers or diastereomers of a chiral molecule may show completely different biological activity. For this reason, it is a vital goal for synthetic chemists to design selective and efficient methodologies that allow the synthesis of the desired enantiomer. LÄS MER