Sökning: "Olefins"

Visar resultat 1 - 5 av 66 avhandlingar innehållade ordet Olefins.

  1. 1. Olefins from carbonyls : Development of new phosphorus-based cross-coupling reactions

    Författare :Nicolas Daniele D'Imperio; Sascha Ott; Carlos Romero-Nieto; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; olefins; carbonyl olefination; phosphaalkenes; stereoselective synthesis; Wittig; Horner-Wadsworth-Emmons; McMurry;

    Sammanfattning : Olefins, compounds containing C=C double bonds, are omnipresent in nature and serve as useful starting materials for various chemical modifications. Olefins are of crucial importance in Medicinal Chemistry and are also present in essential objects like dyes, polymers and plastics. LÄS MER

  3. 2. Asymmetric Hydrogenations : Syntheses of Ligands and Expansion of Substrate Scope

    Författare :Pradeep Cheruku; Pher Andesson; Jay Siegel; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; 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

  4. 3. A tandem Catalyst for hydrogenation of CO2 to light olefins — The role of the zeolite component

    Författare :Wei Di; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Brønsted acid density; MTO reaction; CO2 hydrogenation; tandem catalysts; HCPs; methanol-intermediate; pre-coking; Al distribution; light olefins; SSZ-13 zeolite;

    Sammanfattning : The catalytic conversion of waste CO2 into light olefins offers a sustainable pathway for green chemicals production in the future. Over a tandem catalyst with the bifunctional active sites for methanol synthesis (CTM) and methanol to olefins (MTO), CO2 can be efficiently converted via intermediate methanol into a mixture of light olefins (ethylene, propene, butene). LÄS MER

  5. 4. Enantio- and Regioselective Iridium-Catalyzed Hydrogenation of Olefins : From Development to Total Synthesis

    Författare :Cristiana Margarita; Pher Andersson; Xavier Verdaguer; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Asymmetric hydrogenation; Iridium; Regioselectivity; Kinetic resolution; Total synthesis; organisk kemi; Organic Chemistry;

    Sammanfattning : The work presented in this thesis concerns the iridium-catalyzed asymmetric hydrogenation of cyclic olefins and allylic alcohols for the preparation of useful chiral intermediates with various substitution patterns. The strategy provides stereocontrol for both non-functionalized as well as functionalized substrates and aims to be implemented in the stereoselective preparation of chiral building blocks having more than one stereocenter. LÄS MER

  7. 5. Bridging McMurry and Wittig in One-Pot : Olefins from Stereoselective, Reductive Couplings of Two Aldehydes via Phosphaalkenes

    Författare :Juri Mai; Sascha Ott; Christian Müller; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; carbonyl olefination; reductive aldehyde coupling; stereoselective; organophosphorus; phosphaalkene; phosphanylphosphonate; Wittig; Horner-Wittig; Horner-Wadsworth-Emmons; McMurry; Kemi; Chemistry;

    Sammanfattning : The formation of C=C bonds is of great importance for fundamental and industrial synthetic organic chemistry. There are many different methodologies for the construction of C=C bonds in the literature, but currently only the McMurry reaction allows the reductive coupling of two carbonyl compounds to form alkenes. LÄS MER