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Visar resultat 1 - 5 av 7 avhandlingar som matchar ovanstående sökkriterier.
1. Developments in the Field of Aza-Diels-Alder Reactions, Catalytic Michael Additions and Automated Synthesis
Sammanfattning : The development of new aza-bicyclic structures with potential applications as ligands synthesised via an aza-Diels-Alder cycloaddition has been studied. The studies are concerning the i) development of large scale aza-Diels-Alder reaction, ii) development of a fast and simple route to bicyclic diamine ligands, iii) development of new aza-Diels-Alder adducts from different dienes, iv) development and application of bicyclic N,P ligands for catalytic Michael additions and v) development of robotized asymmetric transfer hydrogenation reactions. LÄS MER
2. Lewis acid Mediated Aza-Diels-Alder Reactions and Asymmetric Alkylations of 2H-azirines
Sammanfattning : This thesis describes the use of 2H-azirines, three-membered unsaturatednitrogen-containing heterocycles, as reactive intermediates ina number of Lewis acid promoted alkylations and Diels-Alderreactions providing synthetically useful aziridines. In order to carry out this investigation a new generalprocedure for the ring closure of vinyl azides, forming theresultant 3-substituted-2H-azirines, was developed applying low boiling solventsin closed reaction vessels at elevated temperatures. LÄS MER
3. Asymmetric Formation and Isomerization of Three-Membered Rings : Catalyst Development and Evaluation
Sammanfattning : Enantiopure α-amino acid derivatives were prepared using a protocol which allows for highly controlled regio- and chemoselectivity in the hydrogenation/ hydrogenolysis of aza-Diels-Alder adducts. One of the resulting α-amino esters, (1S,3R,4R)-2-azabicyclo[2.2.1]heptane-3-carboxylic acid ethyl ester, was utilized further as a catalyst precursor. LÄS MER
4. Organocatalytic Domino Reactions
Sammanfattning : Organocatalyzed reactions involving activation strategies of ketones and aldehydes are important processes in organic chemistry. These activation strategies serve as a versatile platform for the construction of several domino reactions. LÄS MER
5. Synthesis of Novel Chiral Bicyclic Ligands and their Application in Iridium-Catalyzed Reactions
Sammanfattning : The synthesis of 2-aza-norborane derivatives is presented. The use of these compounds in preparation of Ir catalysts for asymmetric hydrogenations is described. The evaluation and optimization of the catalysts as well as the mechanistic aspects of the catalytic process are discussed. LÄS MER
