Sökning: "asymmetric hydrogenation"

Visar resultat 1 - 5 av 58 avhandlingar innehållade orden asymmetric hydrogenation.

1. 1. Asymmetric Hydrogenations : Syntheses of Ligands and Expansion of Substrate Scope

   Författare :Pradeep Cheruku; Pher Andesson; Jay Siegel; Uppsala universitet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Catalysis; Asymmetric; Hydrogenations; Reductions; Olefins; Imines; Enol phosphinates; Transition metal; Complexes; Iridium; Enamines; Ruthenium; Ligands; Trifluoromethyl; Diphenylvinylphosphine oxides; Vinyl phosphonates; Chemistry; Kemi;

   Sammanfattning : Asymmetric hydrogenation has emerged as a versatile methodology to obtain a wide range of chiral precursors. This thesis focused on the synthesis of new chiral ligands and the expansion of the substrate scope of asymmetric hydrogenations. LÄS MER

3. 2. Synthesis and Evaluation of N,P-Chelating Ligands in Asymmetric Transition-Metal-Catalyzed Reactions : Ir-Catalyzed Asymmetric Hydrogenation and Pd-Catalyzed Asymmetric Intermolecular Heck Reaction

   Författare :Päivi Tolstoy; Pher G. Andersson; Göran Hilmersson; Uppsala universitet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; Asymmetric hydrogenation; Heck reaction; N; P ligand; Iridium; Palladium; Asymmetric catalysis; Alkenes; Fluorine; Diarylmethine stereocenters; Chemistry; Kemi; organisk kemi; Organic Chemistry;

   Sammanfattning : This thesis describes synthesis of new chiral N,P ligands and their evaluation in two types of asymmetric transition-metal catalyzed reactions. The first part of the thesis describes studies in iridium-catalyzed asymmetric hydrogenation. LÄS MER

4. 3. Iridium Catalysed Asymmetric Hydrogenation of Pyridines

   Författare :Alban Cadu; Pher G. Andersson; Hans Adolfsson; Uppsala universitet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; hydrogenation; pyridine; catalytic; Iridium; Organisk kemi; Organic Chemistry;

   Sammanfattning : This thesis presents the hydrogenation of substituted pyridines using N,P-ligated iridium catalystsin homogeneous media. These iridium catalysts were developed within this research group in thepast decade. This method of hydrogenation is highly stereoselective, and in several cases good to excellent ees were obtained. LÄS MER

5. 4. Asymmetric Transfer Hydrogenation of Aromatic Ketones : Catalyst Development and Mechanistic Studies

   Författare :Sofia Nordin; Torbjörn Frejd; Uppsala universitet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Organic chemistry; transfer hydrogenation; aza-norbornyl structure; amino acid derivatives; amino alcohols; ruthenium; concerted mechanism; asymmetric catalysis.; Organisk kemi; Organic chemistry; Organisk kemi; organisk kemi; Organic Chemistry;

   Sammanfattning : This thesis describes the development and evaluation of new chiral Ru(arene)(amino alcohol) catalysts for the transfer hydrogenation of aromatic ketones using isopropanol as the hydrogen source. Two mechanistic studies of the Ru(arene)(amino alcohol) catalyzed transfer hydrogenation of acetophenone were also conducted. The Ru(arene)[(1S,3R,4R)-3. LÄS MER

7. 5. Asymmetric Synthesis and Mechanistic Insights of Transition-Metal-Catalyzed Hydrogenation

   Författare :Jianping Yang; Pher G. Andersson; Clément Mazet; Stockholms universitet; []
   Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Asymmetric hydrogenation; Iridium catalysis; Rhodium catalysis; Chiral organofluorine; Enantioconvergent catalysis; Arene hydrogenation; Organic Chemistry; organisk kemi;

   Sammanfattning : The work presented in this thesis is focused on asymmetric synthesis and mechanistic insights of hydrogenations catalyzed by Ir-N,P- and Rh-diphosphine complexes. The developed methodologies provide an efficient catalytic system to access optically enriched compounds by exploiting the effect of the N,P ligand structure and investigating the enantioconvergent behavior. LÄS MER