Search for dissertations about: "radical coupling"

Showing result 1 - 5 of 27 swedish dissertations containing the words radical coupling.

2. 1. 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

4. 2. On the structure of residual lignin in kraft pulping

   Author : Andrea Majtnerová; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; biphenyl structures; kappa number; kraft pulping; phenols; radical coupling; residual delignificaiton; residual lignin; softwood; Cellulose and paper engineering; Cellulosa- och pappersteknik;

   Abstract : .... READ MORE

5. 3. Carbon-Carbon Bond Formation via Radical Cyclization and Transition Metal Catalysis

   Author : Puneet Srivastava; Lars Engman; Ullrich Jahn; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Radical cyclizations; transition metal catalysis; Chemistry; Kemi; Chemistry with specialization in Organic Chemistry; Kemi med inriktning mot organisk kemi;

   Abstract : Free radical cyclization methodology has been used extensively in synthesis for manipulation of complex molecules such as alkaloids, terpenes, carbohydrates, peptides and nucleic acids. The methodology has emerged as a result of work by physical organic chemists who determined rate constants for the most common radical reactions used in organic synthesis. READ MORE

6. 4. Functional Degradable Polymers by a Radical Chemistry approach

   Author : Jenny Undin; Ann-Christine Albertsson; Anna Finne-Wistrand; Jukka Seppälä; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fiber- och polymervetenskap; Fibre and Polymer Science;

   Abstract : One class of polymers that is inherently of great value for many applications is the aliphatic polyesters. Such polymers are very suitable for use as temporary guides, scaffolds, for tissue formation and other biomedical applications, due to their biocompatibility, degradability and appropriate mechanical properties. READ MORE

7. 5. Regulation of Proton Coupled Electron Transfer from Amino Acids in Artificial Model Systems: A Mechanistic Study

   Author : Martin Sjödin; Leif Hammarström; Jan Davidsson; G. Daniel Nocera; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; Proton Coupled Electron Transfer; Tyrosine; Tryptophan; Electron Transfer; Hydrogen bond; Photosystem II; Proton transfer; Radical protein; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi;

   Abstract : Amino acid radicals are key redox intermediates in several natural enzymes including Cytochrome c peroxidase, DNA photolyase, ribonucletide reductase, cytochrome c oxidase and photosystem II. Electron transfer from amino acids is often coupled to deprotonation and this thesis concerns the coupling of electron transfer from tyrosine and tryptophan to trisbipyridineruthenium(III) with deprotonation in model complexes. READ MORE