Sökning: "cyclopropanes"

Visar resultat 1 - 5 av 6 avhandlingar innehållade ordet cyclopropanes.

  1. 1. Asymmetric Synthesis using Redox-Active Diazocompounds as Chiral Carbon Atom Precursors

    Författare :Matteo Costantini; Abraham Mendoza; Armido Studer; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; redox-active carbenes; mechanistic investigation; cyclopropanes; asymmetric catalysis; photochemistry; organisk kemi; Organic Chemistry;

    Sammanfattning : This thesis summarizes the development of general and efficient methods to synthesize enantiomerically enriched cyclopropane compounds. The works reported herein exploit the opportunity presented by redox-active esters to explore the orthogonality between asymmetric carbene-transfer and geminal radical generation. LÄS MER

  3. 2. Novel Applications of Benziodoxole Reagents in the Synthesis of Organofluorine Compounds

    Författare :Nadia O. Ilchenko; Kálmán J. Szabó; Cristina Nevado; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; trifluoromethylation; hypervalent iodine; Togni reagent; difluorination; iodofluorination; organisk kemi; Organic Chemistry;

    Sammanfattning : This thesis concerns method development of new synthetic routes by applying electrophilic hypervalent iodine reagents, such as trifluoromethyl-benziodoxole (Togni reagent) and fluoro-benziodoxole. The first project involved the addition of an oxygen moiety and trifluoromethyl group across double and triple bonds (both groups derived from the hypervalent iodine reagent). LÄS MER

  4. 3. Organocatalytic Domino Reactions

    Författare :Henrik Sundén; Armando Córdova; Pavel Kočovský; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; organocatalytic; domino; iminium-enamine; enamine-iminium; Organic chemistry; Organisk kemi; Organic Chemistry; organisk kemi;

    Sammanfattning : Organocatalyzed reactions involving activation strategies of ketones and aldehydes are important processes in organic chemistry. These activation strategies serve as a versatile platform for the construction of several domino reactions. LÄS MER

  5. 4. Transition-Metal Catalyzed Synthesis of Small- and Medium-Sized Rings Applications toward oxazole synthesis, cycloheptadienes, and natural products

    Författare :Henrik von Wachenfeldt; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; catalysis; transition metal; cyclization; cycloaddition; natural product;

    Sammanfattning : This thesis deals with the development of novel methodologies for the synthesis of hetero- and carbocycles enabled by transition metal catalysis. The second chapter of the thesis describes a gold-catalyzed three-component reaction to form a variety of substituted oxazoles from readily available N-benzylimines, terminal alkynes, and acyl chlorides. LÄS MER

  7. 5. Asymmetric Formation and Isomerization of Three-Membered Rings : Catalyst Development and Evaluation

    Författare :Sophie Bertilsson; Tobias Rein; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Chemistry; allylic alcohol; α-amino acid derivative; aza-Diels-Alder reaction; aziridination; cyclopropanation; desymmetrization; epoxide rearrangement; kinetic resolution; lithium amide; rhodium-carboxylate; Kemi; Chemistry; Kemi; organisk kemi; Organic Chemistry;

    Sammanfattning : Enantiopure α-amino acid derivatives were prepared using a protocol which allows for highly controlled regio- and chemoselectivity in the hydrogenation/ hydrogenolysis of aza-Diels-Alder adducts. One of the resulting α-amino esters, (1S,3R,4R)-2-azabicyclo[2.2.1]heptane-3-carboxylic acid ethyl ester, was utilized further as a catalyst precursor. LÄS MER