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  • 1.
    Bartholomeyzik, Teresa
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Investigation of Selectivity in Palladium-Catalyzed Oxidative Arylating Carbocyclization of Allenynes.Manuscript (preprint) (Other academic)
  • 2.
    Bartholomeyzik, Teresa
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Palladium(II)-Catalyzed Oxidative Carbocyclization/Functionalization of Allenynes2014Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The selective formation of carbon-carbon bonds constitutes a key transformation in organic synthesis with useful applications in pharmaceutical or material industry. A particularly versatile tool for carbon-carbon as well as carbon-heteroatom bond formation is palladium catalysis, which allows for mild and selective routes even towards complex structures.

    The work in this thesis describes the development and the mechanistic investigation of a palladium(II)-catalyzed oxidative carbocyclization/functionalization methodology, which converts 1,5-allenynes into either arylated or borylated carbocycles. To this end, either boronic acids or B2pin2 are employed and 1,4-benzoquinone serves as the stoichiometric oxidant. These protocols provide access to two products, a cyclic triene and a cyclic vinylallene. Their formation is dependent on the substrate structure as the latter product requires a propargylic C–H bond to be present in the substrate. Based on kinetic isotope effects, mechanisms involving either an initial allenic or propargylic C–H abstraction, respectively, were proposed. Full control of product selectivity to give either trienes or vinylallenes was achieved by modifying the reaction conditions with additives. Using substoichiometric amounts of BF3·OEt2 leads selectively to borylated or arylated vinylallenes. Under arylating conditions the reaction is zero order in allenyne and oxidant, and first order in phenylboronic acid. Transmetalation and, to some extent, propargylic C–H cleavage were found to be turnover-limiting. The selective reaction towards functionalized trienes was achieved by addition of either substoichiometric LiOAc·2H2O (borylation) or excess amounts of H2O (arylation). For the latter case, a kinetic study revealed an unusually slow catalyst activation. Lower concentrations of H2O gave product mixtures, and it was shown that vinylallenes are formed with either boronic acid or boroxine, whereas the formation of trienes requires boronic acid.

  • 3.
    Bartholomeyzik, Teresa
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Palladium(II)-Catalyzed Oxidative Carbocyclization/Functionalization of Allenynes2013Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Palladium catalysis has emerged as an outstanding tool in synthetic organic chemistry for the mild and selective formation of carbon-carbon and carbon-heteroatom bonds. This thesis has been directed towards the extension of palladium(II)-catalyzed carbocyclization chemistry under oxidative conditions. An oxidative carbocyclization/functionalization methodology utilizing boron-containing transmetalation reagents was exploited to convert 1,5-allenynes into either arylated or borylated carbocycles. Two protocols were developed that use minimal amounts of Pd(OAc)2, stoichiometric para-benzoquinone as the oxidant and either bis(pinacolato)diboron or different arylboronic acids under mild conditions. A wide substrate scope is applicable to both methods. When the allenyne substrate bears a propargylic hydrogen, two isomeric functionalized carbocycles can be formed. By controlling the reaction conditions the reaction can be directed towards either of these two isomeric products. Kinetic isotope effect studies suggest that the mechanism leading to the different products proceeds through allylic or propargylic C-H bond cleavage, respectively. Moreover, it was observed that water has an interesting effect on the product selectivity when arylboronic acids are used in the oxidative carbocyclization of allenynes.

  • 4.
    Bartholomeyzik, Teresa
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Deng, Youqian
    Bäckvall, Jan-E.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Selective Palladium-catalyzed oxidative carbocyclization of allenynes2013In: Abstracts of Papers of The American Chemical Society, American Chemical Society (ACS), 2013Conference paper (Other academic)
  • 5.
    Bartholomeyzik, Teresa
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Mazuela, Javier
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Pendrill, Robert
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Deng, Youqian
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bäckvall, Jan-Erling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Palladium-Catalyzed Oxidative Arylating Carbocyclization of Allenynes: Control of Selectivity and Role of H2O2014In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 53, no 33, p. 8696-8699Article in journal (Refereed)
    Abstract [en]

    Highly selective protocols for the carbocyclization/arylation of allenynes using arylboronic acids are reported. Arylated vinylallenes are obtained with the use of BF3 center dot Et2O as an additive, whereas addition of water leads to arylated trienes. These conditions provide the respective products with excellent selectivities (generally > 97:3) for a range of boronic acids and different allenynes. It has been revealed that water plays a crucial role for the product distribution.

  • 6.
    Bartholomeyzik, Teresa
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Pendrill, Robert
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Jiang, Tuo
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Widmalm, Göran
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bäckvall, Jan-E.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Complex Kinetics in a Palladium(II)-Catalyzed Oxidative Carbocyclization: Untangling of Competing Pathways, Pre-Catalyst Activation, and Product MixturesManuscript (preprint) (Other academic)
  • 7.
    Deng, Youqian
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bartholomeyzik, Teresa
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Persson, Andreas K. A.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sun, Junliang
    Bäckvall, Jan-E.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Palladium-Catalyzed Oxidative Arylating Carbocyclization of Allenynes2012In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 51, no 11, p. 2703-2707Article in journal (Refereed)
  • 8.
    Deng, Youqian
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Teresa, Bartholomeyzik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bäckvall, Jan-E.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Control of Selectivity in Palladium-Catalyzed Oxidative Carbocyclization/Borylation of Allenynes2013In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, no 24, p. 6283-6287Article in journal (Refereed)
    Abstract [en]

    In control: A highly selective carbocyclization/borylation of allenynes with bis(pinacolato)diboron (B2pin2) under palladium catalysis and with p-benzoquinone (BQ) as the oxidant was developed. The use of either LiOAc⋅2 H2O with 1,2-dichloroethane (DCE) as the solvent or BF3⋅Et2O together with THF is crucial for the selective formation of borylated trienes and vinylallenes, respectively.

  • 9.
    Jiang, Tuo
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bartholomeyzik, Teresa
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Mazuela, Javier
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Willersinn, Jochen
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Bäckvall, Jan-E.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Palladium(II)/Bronsted Acid-Catalyzed Enantioselective Oxidative Carbocyclization-Borylation of Enallenes2015In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 54, no 20, p. 6024-6027Article in journal (Refereed)
    Abstract [en]

    An enantioselective oxidative carbocyclization-borylation of enallenes that is catalyzed by palladium(II) and a Bronsted acid was developed. Biphenol-type chiral phosphoric acids were superior co-catalysts for inducing the enantioselective cyclization. A number of chiral borylated carbocycles were synthesized in high enantiomeric excess.

  • 10. Thorsheim, Karin
    et al.
    Siegbahn, Anna
    Johnsson, Richard E.
    Stalbrand, Henrik
    Manner, Sophie
    Bartholomeyzik, Teresa
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ellervik, Ulf
    Chemistry of xylopyranosides2015In: Carbohydrate Research, ISSN 0008-6215, E-ISSN 1873-426X, Vol. 418, p. 65-88Article, review/survey (Refereed)
    Abstract [en]

    Xylose is one of the few monosaccharidic building blocks that are used by mammalian cells. In comparison with other monosaccharides, xylose is rather unusual and, so far, only found in two different mammalian structures, i.e. in the Notch receptor and as the linker between protein and glycosaminoglycan (GAG) chains in proteoglycans. Interestingly, simple soluble xylopyranosides can not only initiate the biosynthesis of soluble GAG chains but also function as inhibitors of important enzymes in the biosynthesis of proteoglycans. Furthermore, xylose is a major constituent of hemicellulosic xylans and thus one of the most abundant carbohydrates on Earth. Altogether, this has spurred a strong interest in xylose chemistry. The scope of this review is to describe synthesis of xylopyranosyl donors, as well as protective group chemistry, modifications, and conformational analysis of xylose.

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