Sökning: "Wittig"

Visar resultat 1 - 5 av 13 avhandlingar innehållade ordet Wittig.

1. 1. Experiments on biofilm formation and growth in laminar flows

   Författare :Cornelius Wittig; Shervin Bagheri; Thomas Crouzier; Wouter van der Wijngaart; Eleonora Secchi; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; biofilm; streamers; wall shear stress; OCT; Teknisk mekanik; Engineering Mechanics;

   Sammanfattning : The interaction between fluid dynamics and biofilm growth plays a key role in both medical and industrial applications. Biofilms, or bacteria that are embedded in a protective matrix of extracellular polymeric substances, settle on interfaces such as on implanted devices or ship hulls. LÄS MER

3. 2. Bridging McMurry and Wittig in One-Pot : Olefins from Stereoselective, Reductive Couplings of Two Aldehydes via Phosphaalkenes

   Författare :Juri Mai; Sascha Ott; Christian Müller; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; carbonyl olefination; reductive aldehyde coupling; stereoselective; organophosphorus; phosphaalkene; phosphanylphosphonate; Wittig; Horner-Wittig; Horner-Wadsworth-Emmons; McMurry; Kemi; Chemistry;

   Sammanfattning : The formation of C=C bonds is of great importance for fundamental and industrial synthetic organic chemistry. There are many different methodologies for the construction of C=C bonds in the literature, but currently only the McMurry reaction allows the reductive coupling of two carbonyl compounds to form alkenes. LÄS MER

4. 3. Olefins from carbonyls : Development of new phosphorus-based cross-coupling reactions

   Författare :Nicolas Daniele D'Imperio; Sascha Ott; Carlos Romero-Nieto; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; olefins; carbonyl olefination; phosphaalkenes; stereoselective synthesis; Wittig; Horner-Wadsworth-Emmons; McMurry;

   Sammanfattning : Olefins, compounds containing C=C double bonds, are omnipresent in nature and serve as useful starting materials for various chemical modifications. Olefins are of crucial importance in Medicinal Chemistry and are also present in essential objects like dyes, polymers and plastics. LÄS MER

5. 4. Methods for Asymmetric Olefination Reactions; Development and Application to Natural Product Synthesis

   Författare :Daniel Strand; Tobias Rein; Viresh Rawal; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Antitumor agents; Asymmetric Horner-Wadsworth-Emmons; Desymmetrization; Metal-catalyzed olefination; Mucocin; Palladium-catalyzed allylic substitution; Parallel kinetic resolution; Pyranicin; Pyragonicin; Rhenium; Stereoconvergent synthesis; Stereodivergent synthesis; Stereoselective synthesis; Tetrahydropyran; Wittig reaction; Organic chemistry; Organisk kemi;

   Sammanfattning : This thesis deals with the development and application of methods for asymmetric olefinations, in particular Horner-Wadsworth-Emmons (HWE) reactions, in the synthesis of certain natural products. Relying on asymmetric HWE reactions to access key building blocks, two natu-ral products, pyranicin and pyragonicin, were synthesized from common late intermediates. LÄS MER

7. 5. Host-guest chemistry : the effect on the Z/E-selectivity in Wittig reactions in the presence of cyclodextrin

   Författare :Gunnar Westman; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : .... LÄS MER