Sökning: "hydrogenation"

Visar resultat 21 - 25 av 126 avhandlingar innehållade ordet hydrogenation.

  1. 21. Self-adaptable catalysts : Importance of flexibility and applications in asymmetric catalysis

    Författare :Ester Fjellander; Christina Moberg; Jay Siegel; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; adaptable; flexible; semi-flexible; symmetry; conformational study; mechanistic study; rotation barrier; VT NMR; asymmetric catalysis; ligand design; allylic alkylation; hydrogenation; azepines; dioxaphosphepines; phosphepines; amines; phosphines; phosphoramidites; phosphinites; palladium; rhodium; Organic chemistry; Organisk kemi;

    Sammanfattning : The topic of this thesis is the design and synthesis of biaryl-based self adaptableligands for asymmetric metal catalysis. The results discussed in papers I-III are covered, together with some unpublished results concerning substrate-adaptable catalysts. A general survey of self-adaptable catalysts is presented first. LÄS MER

  2. 22. Catalytic and Electrocatalytic Transformations with Palladium and Nickel : Scope and mechanistic investigations

    Författare :Alejandro Valiente Sánchez; Belén Martín-Matute; King Kuok (Mimi) Hii; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Organic Chemistry; Heterogeneous Catalysis; Metal-organic frameworks; Nickel; Palladium; Electrocatalysis; Cross-coupling; Hydrogenation; organisk kemi; Organic Chemistry;

    Sammanfattning : The work presented in this thesis is based on methodology development and mechanistic investigations using heterogeneous palladium and nickel catalysts. Following the introduction (Chapter 1), Chapter 2 presents a summary of the synthesis and characterization of the MOF-supported Pd catalysts (Pd @ MOF) that are used in this thesis. LÄS MER

  3. 23. 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

  4. 24. Flexibility – a tool for chirality control in asymmetric catalysis

    Författare :Raivis Zalubovskis; Christina Moberg; Alexandre Alexakis; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; flexibility; symmetry; dissymmetry; asymmetric catalysis; chiral ligands; pseudo-C2; pseudo-CS; conformational study; rotation barrier; pyrrolidines; phospholanes; azepines; phosphepines; supramolecular; hydrogenation; allylic alkylation; silaboration; palladium; rhodium; nickel; platinum; iridium.; Organic chemistry; Organisk kemi;

    Sammanfattning : This thesis deals with the design and synthesis of ligands for asymmetric catalysis: palladium catalyzed allylic alkylations, and rho-dium and iridium catalyzed hydrogenations of olefins. Chirally flexible phosphepine ligands based on biphenyl were synthesized and their properties were studied. LÄS MER

  5. 25. 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