Sökning: "hydride transfer"

Visar resultat 1 - 5 av 29 avhandlingar innehållade orden hydride transfer.

  1. 1. Selective transfer hydrogenations : Catalyst development and mechanistic investigations

    Författare :Jenny Wettergren; Hans Adolfsson; Serafino Gladiali; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asymmetric catalysis; transfer hydrogenation; transition metal; amino acids; amino alcohols; Organic chemistry; Organisk kemi; Organic Chemistry; organisk kemi;

    Sammanfattning : By generating a library of amino acid-based ligands, pseudo-dipeptides, and combining them with transition metals, we have created selective and efficient ruthenium and rhodium catalysts for the asymmetric transfer hydrogenation of ketones. The ruthenium-catalyzed reaction was studied in detail, and we found that alkali metals play a crucial role for the reactivity and selectivity of the reaction. LÄS MER

  3. 2. Hydrogenation, Transfer Hydrogenation and Hydrogen Transfer Reactions Catalyzed by Iridium Complexes

    Författare :Xu Quan; Pher Andersson; Jonathan Williams; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Iridium catalyst; carbene; N; P - ligand; asymmetric hydrogenation; transfer hydrogenation; hydrogen transfer reaction; alkylation; olefin; ketone; amide; organisk kemi; Organic Chemistry;

    Sammanfattning : The work described in this thesis is focused on the development of new bidentate iridium complexes and their applications in the asymmetric reduction of olefins, ketones and imines. Three new types of iridium complexes were synthesized, which included pyridine derived chiral N,P-iridium complexes, achiral NHC complexes and chiral NHC-phosphine complexes. LÄS MER

  4. 3. Investigations of New Biomimetic Transamination Systems and Inclusion Complexation with Cyclodextrins

    Författare :Anders Hjelmencrantz; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; stereochemis; bicyclooctanes.Transamination; complexation; cyclodextrins; proton transfer; hydride transfer; stereochemistry; Transamination; Organic chemistry; Organisk kemi;

    Sammanfattning : Two new transamination systems are described. The first example is a dibenzo[a,d]- cycloheptene containing system, designed to accomplish a [1,3]-hydride transfer. Several catalysts have been examined for this purpose. tris-Pentafluorophenyl borane was found to be the most efficient catalyst. LÄS MER

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

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

    Sammanfattning : 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. LÄS MER

  7. 5. Asymmetric Transfer Hydrogenation of Aromatic Ketones : Catalyst Development and Mechanistic Studies

    Författare :Sofia Nordin; Torbjörn Frejd; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic chemistry; transfer hydrogenation; aza-norbornyl structure; amino acid derivatives; amino alcohols; ruthenium; concerted mechanism; asymmetric catalysis.; Organisk kemi; Organic chemistry; Organisk kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : This thesis describes the development and evaluation of new chiral Ru(arene)(amino alcohol) catalysts for the transfer hydrogenation of aromatic ketones using isopropanol as the hydrogen source. Two mechanistic studies of the Ru(arene)(amino alcohol) catalyzed transfer hydrogenation of acetophenone were also conducted. The Ru(arene)[(1S,3R,4R)-3. LÄS MER