Sökning: "photochemistry"
Visar resultat 21 - 25 av 73 avhandlingar innehållade ordet photochemistry.
21. C–H and Si–H functionalization using redox-active diazo compounds and decarboxylative coupling
Sammanfattning : The work presented in this thesis is based on two basic organic chemistry concepts: carbene catalysis and radical coupling reactions. Diazo compounds in the presence of transition-metal catalysts are known to be excellent reagents for the construction of C–X bonds (X = C, Si, N, O, etc.) under mild conditions. LÄS MER
22. Light-Induced Routes to Sustainable Biocrudes for Fuels and Lubricant Oils
Sammanfattning : Fossil-based hydrocarbons are at present the ideal compounds for jet fuels and lubricant oils, so their replacement by novel technologies is not easy. Instead, sustainable routes to hydrocarbons, such as sunlight-driven processes, are desired to reduce the environmental impact by the transport sector. LÄS MER
23. Asymmetric Synthesis using Redox-Active Diazocompounds as Chiral Carbon Atom Precursors
Sammanfattning : This thesis summarizes the development of general and efficient methods to synthesize enantiomerically enriched cyclopropane compounds. The works reported herein exploit the opportunity presented by redox-active esters to explore the orthogonality between asymmetric carbene-transfer and geminal radical generation. LÄS MER
24. The importance of terrestrial carbon in plankton food webs
Sammanfattning : Allochthonous substances, i.e. produced in terrestrial ecosystems, are known to fuel bacterial production in humic lakes. I observed that allochthonous carbon subsidizes bacteria even at high levels of phytoplankton biomass. LÄS MER
25. Extending the Reach of Accurate Wavefunction Methods
Sammanfattning : Multiconfigurational quantum chemistry methods, and especially the multiconfigurational self-consistent field (MCSCF) and multireference perturbation theory (MRPT2), are powerful tools, particularly suited to the accurate modeling of photochemical processes and transition metal catalysis. However, they are limited by their high computational cost compared to other methods, especially density functional theory. LÄS MER