Sökning: "asymmetric transfer hydrogenation"

Visar resultat 1 - 5 av 26 avhandlingar innehållade orden asymmetric transfer hydrogenation.

1. 1. Hydrogenation, Transfer Hydrogenation and Hydrogen Transfer Reactions Catalyzed by Iridium Complexes

   Författare :Xu Quan; Pher Andersson; Jonathan Williams; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Iridium catalyst; carbene; N; P - ligand; asymmetric hydrogenation; transfer hydrogenation; hydrogen transfer reaction; alkylation; olefin; ketone; amide; organisk kemi; Organic Chemistry;

   Sammanfattning : The work described in this thesis is focused on the development of new bidentate iridium complexes and their applications in the asymmetric reduction of olefins, ketones and imines. Three new types of iridium complexes were synthesized, which included pyridine derived chiral N,P-iridium complexes, achiral NHC complexes and chiral NHC-phosphine complexes. LÄS MER

3. 2. Asymmetric Transfer Hydrogenation of Aromatic Ketones : Catalyst Development and Mechanistic Studies

   Författare :Sofia Nordin; Torbjörn Frejd; Uppsala universitet; []
   Nyckelord :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

4. 3. Ruthenium-Catalyzed Asymmetric Transfer Hydrogenation

   Författare :Tove Slagbrand; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; allylic alcohols; asymmetric catalysis; isomerization; reduction; ruthenium;

   Sammanfattning : This thesis covers the development of two new methods for the asymmetric reduction of ketones and ketone intermediates. The protocols developed are based on the use of a ruthenium pseudo-dipeptide catalyst that previously has been shown to be efficient and selective in the asymmetric reduction of carbonyl compounds. LÄS MER

5. 4. Asymmetric transfer hydrogenation of ketones : Catalyst development and mechanistic investigation

   Författare :Katrin Ahlford; Hans Adolfsson; Martin Wills; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Asymmetric catalysis; reduction; amino acid; rhodium; mechanistic investigation; kinetic study; Organic chemistry; Organisk kemi; organisk kemi; Organic Chemistry;

   Sammanfattning : The development of ligands derived from natural amino acids for asymmetric transfer hydrogenation (ATH) of prochiral ketones is described herein. In the first part, reductions performed in alcoholic media are examined, where it is found that amino acid-derived hydroxamic acids and thioamides, respectively, are simple and versatile ligands that in combination with [RhCp*Cl2]2 efficiently catalyze this particular transformation. LÄS MER

7. 5. Selective transfer hydrogenations : Catalyst development and mechanistic investigations

   Författare :Jenny Wettergren; Hans Adolfsson; Serafino Gladiali; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; asymmetric catalysis; transfer hydrogenation; transition metal; amino acids; amino alcohols; Organic chemistry; Organisk kemi; Organic Chemistry; organisk kemi;

   Sammanfattning : By generating a library of amino acid-based ligands, pseudo-dipeptides, and combining them with transition metals, we have created selective and efficient ruthenium and rhodium catalysts for the asymmetric transfer hydrogenation of ketones. The ruthenium-catalyzed reaction was studied in detail, and we found that alkali metals play a crucial role for the reactivity and selectivity of the reaction. LÄS MER