Search for dissertations about: "stereochemistry"
Showing result 21 - 25 of 44 swedish dissertations containing the word stereochemistry.
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21. Development of an Asymmetric Synthesis of Glionitrin A and B
Abstract : In this thesis, studies in the chemical synthesis of the dithiodiketopiperazine natural products (—)-glionitrin A and B are described.In Chapter 2, a synthesis of the indoline-fused 2,5-diketopiperazine core of glionitrin A and B using a C-H activation approach is described. READ MORE
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22. Transition metal-catalysis: Applications of dynamic kinetic resolution in total synthesis and developments of novel methodologies using heterogeneous Pd catalysts
Abstract : The first part of the thesis describes a general and efficient route for the enantioselective synthesis of various α-substituted ketones and their corresponding lactones. The two key steps in this synthesis are the ruthenium and CALB-catalyzed dynamic kinetic resolution (DKR) which provided the exocyclic acetates in high yields and excellent enantioselectivity and the subsequent Cu-catalyzed α-allylic substitution giving the corresponding α-substituted products with inversed stereochemistry in high yields. READ MORE
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23. Modulation of Molecular Properties : Host–Guest Interactions for Structural Analysis and Chemical Reactions
Abstract : This thesis concerns the construction, use and modulation of various host–guest systems, from small bispidines for binding of inorganic ions to bisporphyrin clips for supramolecular systems.Small flexible molecules undergo fast conformational movements when in solution. READ MORE
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24. Asymmetric transformation of ß- and γ-functionalized alcohols : Study of combined ruthenium-catalyzed racemization and enzymatic resolution
Abstract : The major part of this thesis describes the asymmetric synthesis of β- and γ-amino alcohols through the combination of ruthenium catalyzed racemization and enzymatic kinetic resolution. The dynamic kinetic resolution, DKR, protocol for chlorohydrins was improved by employing Bäckvall’s catalyst, which is a base activated racemization catalyst, in combination with Burkholderia cepacia lipase. READ MORE
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25. Transition-Metal Catalyzed Synthesis of Small- and Medium-Sized Rings Applications toward oxazole synthesis, cycloheptadienes, and natural products
Abstract : This thesis deals with the development of novel methodologies for the synthesis of hetero- and carbocycles enabled by transition metal catalysis. The second chapter of the thesis describes a gold-catalyzed three-component reaction to form a variety of substituted oxazoles from readily available N-benzylimines, terminal alkynes, and acyl chlorides. READ MORE
