Search for dissertations about: "diphosphine"

Showing result 1 - 5 of 8 swedish dissertations containing the word diphosphine.

  2. 1. Metallacyclic Phosphine Complexes and Intramolecular Csp3-H Bond Activation -Synthesis, Characterisation and Catalytic Application

    Author : Sven Sjövall; Kemiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; catalysis; Heck; diphosphite; diphosphine; phosphine; cyclometallation; C-C activation; C-O activation; C-H activation; palladium; rhodium; iridium; Inorganic chemistry; Oorganisk kemi;

    Abstract : The work presented in this thesis deals with metallacyclic late transition metal complexes, obtained by intramolecular Csp3-H activation, and the application of such compounds in catalysis. The new hemilabile P,O phosphines N-methyl-N-propionyl-2-(diphenylphosphino)benzylamine (DPPAM), o-(diphenylphosphino)benzoic acid ethyl ester (DPPES), o-(diphenylphosphino)benzoic acid methyl ether (DPPET) and ±-1-(2- diphenylphosphino)phenylethyl propionate (±-DPPMES) and the symmetrical diphosphorus donor ligands cis-1,3-bis[(diphenylphosphino)methyl]-cyclohexane (DPCY), cis-1,3-bis[(di-tertbutylphosphino)methyl]cyclohexane (DTBCY) and cis-1,3-bis[(di-isopropylphosphino)methyl]cyclohexane (DIPCY) have been synthesised, allowing the preparation of a range of new metallacyclic rhodium(III), iridium(III) and palladium(II) complexes. READ MORE

  4. 2. Iron Carbonyl Clusters as Proton Reduction Catalysts

    Author : Ahibur Rahaman; Kemisk fysik; []
    Keywords : iron-only hydrogenase; phosphine-substitution; electrocatalysis; proton reduction;

    Abstract : Abstract – The mixed-valence triiron complexes [Fe3(CO)7-x(PPh3)x(µ-edt)2] (x = 0, 1, 2; edt = SCH2CH2S) and [Fe3(CO)5(κ2-diphosphine)(µ-edt)2] (diphosphine = dppv, dppe, dppb, dppn) have been prepared and structurally characterized. In comparison to the diiron complex [Fe2(CO)6(µ-edt)], [Fe3(CO)7(µ-edt)2] catalyzes proton reduction at 0. READ MORE

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

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

    Abstract : 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. READ MORE

  6. 4. Cluster-Based Catalysts for Asymmetric Synthesis

    Author : Viktor Moberg; Kemisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Metallorganisk kemi; Organometallic chemistry; Oorganisk kemi; Inorganic chemistry; Kemi; Chemistry; hydride; cobalt; osmium; ruthenium; cyclocarbonylation; Pauson-Khand; carbonyl cluster; asymmetric hydrogenation;

    Abstract : In this work, the synthesis and characterisation of new low-valence transition metal carbonyl clusters, and an investigation into their viability to act as catalysts/catalyst precursors in asymmetric synthesis, are described. Carbonyl clusters based on ruthenium and osmium have been tested as (pre)catalysts for asymmetric hydrogenation of alpha-unsaturated carboxylic acids, and cobalt carbonyl clusters have been used as (pre)catalysts in (asymmetric) Pauson-Khand synthesis. READ MORE

  7. 5. Homogeneous and Heterogeneous Cluster-Based Catalysts for Asymmetric Reactions

    Author : Ahmed Fawzy; Kemisk fysik; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Asymmetric synthesis; hydrogenation; ruthenium; osmium; rhenium; phosphine ligands; chirality.;

    Abstract : Synthesis and characterization of new transition metal carbonyl clusters has been undertaken, and evaluation of the new clusters to act as catalysts/catalysts precursor in asymmetric reactions has been carried out. The catalytic hydrogenation of tiglic acid under relatively mild conditions, using diastereomeric clusters of the general formula [(µ-H)2Ru3(µ3-S)(CO)7(µ-1,2-L)] (L= chiral diphosphine of the ferrocene-based Walphos and Josiphos families) as catalysts, reveal different catalytic behavior in terms of conversion and enantioselectivity. READ MORE