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Visar resultat 1 - 5 av 6 avhandlingar som matchar ovanstående sökkriterier.

  1. 1. Design and synthesis of rhodium and iridium bis-η2 diolefin catalysts: : Applications in C–C bond formation and asymmetric catalysis

    Författare :Michaela Melcher; Centrum för analys och syntes; []
    Nyckelord :catalysis; transition metal; ligand design; enantioselectivity; cycloadditions;

    Sammanfattning : This thesis deals with the design and synthesis of rhodium and iridium bis-η2 diolefin catalysts and their applications in C–C bond formation and asymmetric catalysis.More specifically, the second chapter describes the development of inter- and intramolecular (5+2) cycloadditions catalyzed by cationic iridium(I) complexes that lead to the formation of seven-membered rings in a single step. LÄS MER

  3. 2. Synthesis of Nitrogen Heterocycles via 1,3-Dipolar Cycloadditions - Method Development and Applications

    Författare :Johan Johansson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; 2D NOESY; alkyne; 3-dipolar cycloaddition; azomethine ylide; 1; CNTs; azide; sequential one-pot; SEM EDS; microwave heating; RuAAC; CuAAC;

    Sammanfattning : Because of the diverse properties displayed by nitrogen heterocycles, they are one of the most commonly used structural elements in drug discovery. Due to this variation in properties, however, the chemistry and synthetic pathway to each heterocycle is unique. LÄS MER

  4. 3. Stereoselectivity in organic chemistry : asymmetric 1,3-dipolar cycloadditions and rule-based conformational analysis

    Författare :Kaye Stern; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; molecular mechanics; nitrile oxides; Stereochemistry; nitrone;

    Sammanfattning : .... LÄS MER

  5. 4. Lewis Acid Mediated Alkylation and Diels-Alder Reactions of 2H-Azirines

    Författare :Erik Risberg; KTH; []
    Nyckelord :2H-azirines; Lewis acid activation; chiral ligandsorganolithium reagentsDiels-Alder reactions; DFT-calculations;

    Sammanfattning : This thesis describes the use of 2H-azirines as reactivesubstrates in Lewis acid catalysed nucleophilic additions andin the Diels-Alder reaction.A number of carbon nucleophiles have been added to aseries of 2H-azirines in the presence and absence ofBF3·Et2O. LÄS MER

  7. 5. Natural Product Synthesis and Development of Novel Reaction Methodology

    Författare :Jakob Danielsson; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; perophoramidine; communesin; quaternary stereocenter; Diels-Alder; 1; 2-asymmetric induction; polar Felkin-Anh; Cornforth-Evans; Mukaiyama aldol; 3-dipolar cycloaddition; azomethine ylide; 2-amino alcohol; anti-α-amino-β-hydroxy ester;

    Sammanfattning : This thesis deals with the development of new reaction methodology for stereoselective synthesis, as well as total synthesis of natural products and investigations of the stereochemical outcome in the Mukaiyama aldol reaction. Chapter 2 describes efforts made towards the total synthesis of the oxindole natural products perophoramidine and the communesin. LÄS MER