Search for dissertations about: "Isomerization"

Showing result 1 - 5 of 95 swedish dissertations containing the word Isomerization.

2. 1. Thermal Isomerization of Azobenzene Side Chain Copolymers

   Author : Viktoria Skeppstedt; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; free volume; thermal isomerization; positron annihilation lifetime spectroscopy; physical ageing; phthalate; methyl methacrylate polymer; azo polymers; plasticization;

   Abstract : Irradiation of azobenzene induces isomerization between its trans- and cis forms. By introduction of azobenzene chromophores in polymers, it is possible to optically control a variety of polymer properties. The isomerization of azobenzene can be used to influence conformational, optical or surface properties of the poly mer material. READ MORE

4. 2. Selective Transformations of Allylic Compounds and Enol Derivatives : Synthesis of Fluorinated and Nitrogenated Scaffolds

   Author : Víctor García-Vázquez; Belén Martín‐Matute; Mario Waser; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Fluorinated compounds; Base catalysis; Ion-Pair; Isomerization; Pd catalysis; Method development; Hypervalent iodine III ; Organic Chemistry; organisk kemi;

   Abstract : In this thesis, new synthetic methods to give access to molecules having fluorinated scaffolds and other polar functional groups have been developed. The methods give access to highly valuable organic compounds that may serve as building blocks in the synthesis of functionalized drug candidates. READ MORE

5. 3. Controlling the Fluorescence Properties of Diarylethene-based Photochromic Systems

   Author : Gaowa Naren; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; isomerization; color change; photochromic molecules; molecular logic; intensity modulation; diarylethene; RGB; all-photonic; FRET;

   Abstract : Diarylethene (DAE) photoswitches are one of the most promising families of photochromic molecules because of their outstanding photophysical/photochemical properties. This class of compounds, which can photoisomerize between an open colorless and a closed colored form, has been applied in various fields in this thesis work, spanning one-color fluorescence intensity modulation, all-photonic full-color reproduction, light-induced color changes for molecular logic gates and information processing. READ MORE

6. 4. Catalytic Methods to Convert Allylic Substrates through Hydride and Proton Shifts : Transition Metal-Catalyzed and Organocatalyzed Approaches

   Author : Samuel Martinez-Erro; Belén Martín-Matute; Franziska Schoenebeck; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Allylic substrates; Iridium catalysis; Base catalysis; Method development; Isomerization; Hydride shift; Proton shift; Mechanistic studies; organisk kemi; Organic Chemistry;

   Abstract : The present thesis describes the development of new catalytic protocols to transform allylic substrates into a wide variety of versatile carbonyl and vinyl organic compounds. All procedures that are described in this work have in common the existence of one or more hydrogen shifts as key steps in the mechanism of the reactions. READ MORE

7. 5. Quantum Chemical Studies of Radical Cation Rearrangement, Radical Carbonylation, and Homolytic Substitution Reactions

   Author : Daniel Norberg; Nessima Salhi-Benachenhou; Sten Lunell; Tim Clark; Uppsala universitet; []
   Keywords : Quantum chemistry; quantum chemistry; coupled-cluster; density functional theory; meta-GGA; reaction mechanism; potential energy surface; isomerization; fragmentation; dissociation; condensation; addition; SH2; hydrogen abstraction; iodine atom transfer; complex; weakly interacting system; hyperfine coupling constant; Kvantkemi;

   Abstract : Quantum chemical calculations have been performed to investigate radical cation rearrangement, radical carbonylation, and homolytic substitution reactions of organic molecules. The rearrangement of the bicyclopropylidiene radical cation to the tetramethyleneethane radical cation is predicted to proceed with stepwise disrotatory opening of the two rings. READ MORE