Sökning: "carbene"

Visar resultat 1 - 5 av 35 avhandlingar innehållade ordet carbene.

  1. 1. NHC,P- and N,P-Iridium Catalysts for Hydrogenations and Hydrogen Transfer Reactions

    Författare :Sutthichat Kerdphon; Pher Andersson; Anton Vidal; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Iridium catalyst; carbene; N; P-ligand; asymmetric hydrogenation; alkylation; hydrogen transfer reaction; organisk kemi; Organic Chemistry;

    Sammanfattning : The work described in this thesis is focused on hydrogenation and hydrogen transfer reactions using iridium catalysts. The first part concerns the use of N-heterocyclic carbene-phosphine iridium complexes in alkylation reactions (Chapters 2 and 3) and the hydrogenation of ketones (Chapter 4). LÄS MER

  3. 2. 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

  4. 3. Development of new Fluorination Methods Directed to Fluorine-18 Labelling

    Författare :Miguel Ángel Cortés González; Kálmán J. Szabó; Guosheng Liu; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; fluorine; fluorine-18; late-stage; labelling; nucleophilic; electrophilic; fluorination; positron emision tomography; PET; hypervalent iodine; benziodoxole; metal-free; DBU; copper; palladium; rhodium; carbene; organisk kemi; Organic Chemistry;

    Sammanfattning : This thesis deals with the development of new fluorination reactions and their application to fluorine-18 labelling. Fluorine-18 labelled compounds are employed as tracers in Positron Emission Tomography (PET), which is a powerful non-invasive imaging method in medical diagnostics. LÄS MER

  5. 4. Lewis acid promoted endocyclic cleavage of glycosides and related acetals

    Författare :Roger Olsson; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; halichomycin; allylation; carbene; hydrogen bond; organozinc; organotitanium; furanosides; organoaluminium; pyranosides; glycosides; stereoselective; endocyclic cleavage; nucleophilic ring opening; ab initio; Organic chemistry; Organisk kemi;

    Sammanfattning : This thesis is a summary of five papers concerning endocyclic cleavage of glycosides and related acetals. Simple lactol ethers undergo endocyclic cleavage to give acyclic chain extended products on treatment with organoaluminium and organotitanium reagents. LÄS MER

  7. 5. Carbenes: The Gathering : Photophysics of Transition Metal Carbene Complexes

    Författare :Nidhi Kaul; Leif Hammarström; James K. McCusker; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; photophysics; time-resolved spectroscopy; transition-metal complexes; Kemi med inriktning mot kemisk fysik; Chemistry with specialization in Chemical Physics;

    Sammanfattning : This thesis explores the photophysics of some transition-metal complexes (TMCs) which utilize N-heterocyclic carbenes as ligands. After a historical interlude which traces the development of the broader field of transition metal complexes and their photophysical investigations, there is an overview of theoretical concepts and the spectroscopic methods employed. LÄS MER