Sökning: "Lewis acid catalyst"

Visar resultat 1 - 5 av 12 avhandlingar innehållade orden Lewis acid catalyst.

  1. 1. Aspects on the Regio and Stereo Selectivity in the Hydrolsilylation of 1,3-Dienes

    Författare :Magnus Gustafsson; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Metallorganisk kemi; Organometallic chemistry; Organisk kemi; Organic chemistry; Lewis acid; electrophilic ring closure; asymmetric hydrosilylation; reaction conditions; isoprene; regioselectivity; oxygen; Wilkinsons catalyst; 15N-1H-HMQC; 31P; heterobidentate ligands; catalyst; palladium; epoxy-allylsilanes; rhodium complexes; dienes;

    Sammanfattning : This thesis is a summary of four papers concerning various aspects on the transition metal catalysed hydrosilylation of 1,3-dienes. The hydrosilylation reaction is formally an addition of a hydrosilane to an unsaturated system and depending on the reaction conditions, control of stereo-, regio-, and chemo-selectivity can be achieved. LÄS MER

  2. 2. Efficient Synthesis and Analysis of Chiral Cyanohydrins

    Författare :Stina Lundgren; Christina Moberg; Ben Feringa; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asymmetric catalysis; cyanohydrins; microreactor; polymersupported catalyst; ketonitriles; titanium; lanthanide; Lewis acid; Lewis base; Organic chemistry; Organisk kemi;

    Sammanfattning : This thesis deals with the development of new methods for efficient synthesis and analysis in asymmetric catalysis. It focuses on the preparation of chiral cyanohydrins by enantioselective addition of cyanide to prochiral aldehydes. LÄS MER

  3. 3. Impact of Secondary Interactions in Asymmetric Catalysis

    Författare :Anders Frölander; Christina Moberg; Gerard van Koten; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asymmetric catalysis; secondary interaction; hydrogen bond; chiral ligand; allylic alkylation; hydrosilylation; cyanation; pymox; box; PHOX; pybox; palladium; iridium; rhodium; Lewis acid; Lewis base; Organic chemistry; Organisk kemi;

    Sammanfattning : This thesis deals with secondary interactions in asymmetric catalysis and their impact on the outcome of catalytic reactions. The first part revolves around the metal-catalyzed asymmetric allylic alkylation reaction and how interactions within the catalyst affect the stereochemistry. LÄS MER

  4. 4. Direct Catalytic Nucleophilic Substitution of Non-Derivatized Alcohols

    Författare :Anon Bunrit; Joseph Samec; Joseph Moran; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nucleophilic substitution; catalysis; alcohols; stereospecific; Lewis acid; Brønsted acid base; bifunctional; heterocycles; organisk kemi; Organic Chemistry;

    Sammanfattning : This thesis focuses on the development of methods for the activation of the hydroxyl group in non-derivatized alcohols in substitution reactions. The thesis is divided into two parts, describing three different catalytic systems. LÄS MER

  5. 5. Carbocation Catalysis for Organic Synthesis

    Författare :Shengjun Ni; Johan Franzén; Bernd Plietker; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; carbocation; trityl cation; Lewis acid catalyst; enantioselective; chiral counteranion; oxa-Diels–Alder; bromination; aldehyde–olefin metathesis; Kemi; Chemistry;

    Sammanfattning : The most common view of carbocations in organic chemistry is that they are short-lived intermediates in several fundamental reactions, e.g. the classic SN1-reaction. LÄS MER