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  • 101.
    Babu, Beneesh P.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Meng, Xu
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Aerobic Oxidative Coupling of Arenes and Olefins through a Biomimetic Approach2013Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 19, nr 13, s. 4140-4145Artikkel i tidsskrift (Fagfellevurdert)
  • 102. Back, Marcus
    et al.
    Nyhlen, Jonas
    Kvarnstrom, Ingemar
    Appelgren, Sara
    Borkakoti, Neera
    Jansson, Katarina
    Lindberg, Jimmy
    Nystrom, Susanne
    Hallberg, Anders
    Rosenquist, Asa
    Samuelsson, Bertil
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Design, synthesis and SAR of potent statine-based BACE-1 inhibitors: Exploration of P1 phenoxy and benzyloxy residues2008Inngår i: Bioorganic & Medicinal Chemistry, ISSN 0968-0896, E-ISSN 1464-3391, Vol. 16, nr 21, s. 9471-9486Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Several BACE-1 inhibitors with low nanomolar level activities, encompassing a statine-based core structure with phenyloxymethyl- and benzyloxymethyl residues in the P1 position, are presented. The novel P1 modi. cation introduced to allow the facile exploration of the S1 binding pocket of BACE-1, delivered highly promising inhibitors.

  • 103. Back, Marcus
    et al.
    Nyhlén, Jonas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kvarnström, Ingemar
    Rosenquist, Åsa
    Samuelsson, Bertil
    Design, synthesis and SAR of potent statin-based β-secretase inhibitors: Exploration of P1 phenoxy and benzyloxy residues2007Konferansepaper (Annet vitenskapelig)
  • 104.
    Bacsik, Zoltan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Ahlsten, Nanna
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Ziadi, Asraa
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Zhao, Guoying
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Garcia-Bennett, Alfonso E.
    Uppsala universitet.
    Martin-Matute, Belen
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Hedin, Niklas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Mechanisms and Kinetics for Sorption of CO(2) on Bicontinuous Mesoporous Silica Modified with n-Propylamine2011Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 27, nr 17, s. 11118-11128Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We studied equilibrium adsorption and uptake kinetics and identified molecular species that formed during sorption of carbon dioxide on amine-modified silica. Bicontinuous silicas (AMS-6 and MCM-48) were postsynthetically modified with (3-aminopropyl)triethoxysilane or (3-aminopropyl)methyldiethoxysilane, and amine-modified AMS-6 adsorbed more CO(2) than did amine-modified MCM-48. By in situ FTIR spectroscopy, we showed that the amine groups reacted with CO(2) and formed ammonium carbamate ion pairs as well as carbamic acids under both dry and moist conditions. The carbamic acid was stabilized by hydrogen bonds, and ammonium carbamate ion pairs formed preferably on sorbents with high densities of amine groups. Under dry conditions, silylpropylcarbamate formed, slowly, by condensing carbamic acid and silanol groups. The ratio of ammonium carbamate ion pairs to silylpropylcarbamate was higher for samples with high amine contents than samples with low amine contents. Bicarbonates or carbonates did not form under dry or moist conditions. The uptake of CO(2) was enhanced in the presence of water, which was rationalized by the observed release of additional amine groups under these conditions and related formation of ammonium carbamate ion pairs. Distinct evidence for a fourth and irreversibly formed moiety was observed under sorption of CO(2) under dry conditions. Significant amounts of physisorbed, linear CO(2) were detected at relatively high partial pressures of CO(2), such that they could adsorb only after the reactive amine groups were consumed.

  • 105.
    Balan, Daniela
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    The three-component aza-Baylis-Hillman reaction: development and application2004Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The current thesis presents the optimization and generalization of the Baylis-Hillman reaction applied to in situ generated imines, i.e. a three-component aza- Baylis-Hillman reaction. We found that the title reaction proceeds most efficiently in the presence of a combination of catalysts, i.e. 3-hydroxyquinuclidine (0.15 equiv) and titanium isopropoxide (0.02 equiv), together with molecular sieves (4 Å; activated powder; 200 mg/mmol substrate) at ambient temperature.

    Our study of the scope and limitations of this reaction, revealed that arylaldehydes and sulfonamides are the only imine precursors which both generate the corresponding imines in situ and facilitate a further reaction with the Michael acceptor in a Baylis-Hillman fashion. Among the Michael acceptors tested, acrylates and acrylonitrile demonstrate high reactivity, while acrylamides and β-substituted acrylates do not participate in the reaction.

    The optimized conditions applied to the above range of substrates results in good-to-excellent yields of the desired amine-products (53-94%) and very high chemoselectivity (83- >99%). Furthermore, the reaction times observed under these conditions are considerably shorter than those previously reported for the aza-Baylis-Hillman reaction.

    In the development of a stereoselective version of the title reaction, the use of a chiral catalyst proved to be most effective. Thus, an enantiomeric excess up to 74% can be obtained with β-Isocupreidine. With chiral imine precursors or chiral acrylates, the diastereoselectivity attained was poor. No asymmetric induction was observed when chiral Lewis acids were employed as a co-catalyst.

    The α-methylene-β-amino acid derivatives obtained via the three-component aza-Baylis-Hillman reaction were subjected to further transformation. Carbon chain elongation at the olefinic end of the amine-adduct was attempted. For this purpose, the Miyaura borylation protocol could be successfully applied. The subsequent Suzuki-type cross-coupling reaction resulted predominantly in hydrolysis of the boronate intermediate, together with formation of the amine-adduct via β-hydride elimination. The optimal conditions for this latter reaction remain to be found.

    Finally, 2,5-dihydropyrroles have been synthesized from aza-Baylis-Hillman adducts, via a short and efficient route in which the key step is a microwave-assisted ring-closing metathesis of the N-allylated amine-adducts.

  • 106.
    Balan, Daniela
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Adolfsson, Hans
    Chiral quinuclidine-based amine catalysts for the asymmetric one-pot, three-component aza-Baylis–Hillman reaction2003Inngår i: Tetrahedron Letters, Vol. 44, nr 12, s. 2521-2524Artikkel i tidsskrift (Fagfellevurdert)
  • 107.
    Balan, Daniela
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Adolfsson, Hans
    Efficient microwave-assisted formation of functionalized 2,5-dihydropyrroles using ruthenium-catalyzed ring-closing metathesis2004Inngår i: Tetrahedron Letters, Vol. 45, nr 15, s. 3089-3092Artikkel i tidsskrift (Fagfellevurdert)
  • 108.
    Balan, Daniela
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Adolfsson, Hans
    Selective formation of α-methylene-β-amino acid derivatives through the aza version of the baylis-Hillman reaction2001Inngår i: The Journal of Organic Chemistry, Vol. 66, s. 6498-6501Artikkel i tidsskrift (Fagfellevurdert)
  • 109.
    Balan, Daniela
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Adolfsson, Hans
    Titanium isopropoxide as Efficient Catalyst for the aza-Baylis-Hillman reaction. Selective formation of α-methylene-β-amino acid derivatives2002Inngår i: The Journal of Organic Chemistry, Vol. 67, s. 2329-2334Artikkel i tidsskrift (Fagfellevurdert)
  • 110. Barbion, Julien
    et al.
    Sorin, Geoffroy
    Selkti, Mohamed
    Kellenberger, Esther
    Baati, Rachid
    Santoro, Stefano
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Himo, Fahmi
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pancrazi, Ange
    Lannou, Marie-Isabelle
    Ardisson, Janick
    Stereoselective functionalization of pyrrolidinone moiety towards the synthesis of salinosporamide A2012Inngår i: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 68, nr 32, s. 6504-6512Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An important feature of the synthesis of salinosporamide A. a potent proteasome inhibitor, is the establishment of the quaternary stereocenter at C3. A new route has been developed based on the methylation of a functionalized pyrrolidinone. Direct methylation reaction led to the unwanted diastereomer: however, by means of a Corey-Chaykovsky reaction followed by LiAlH4 epoxide opening, the desired alcohol was obtained. The pyrrolidinone was elaborated through a key allylation reaction between a tertiary allyltitanium reagent and an aldehyde bearing a spiroketal moiety in alpha-position.

  • 111.
    Bartholomeyzik, Teresa
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Investigation of Selectivity in Palladium-Catalyzed Oxidative Arylating Carbocyclization of Allenynes.Manuskript (preprint) (Annet vitenskapelig)
  • 112.
    Bartholomeyzik, Teresa
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium(II)-Catalyzed Oxidative Carbocyclization/Functionalization of Allenynes2014Doktoravhandling, med artikler (Annet vitenskapelig)
    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.

  • 113.
    Bartholomeyzik, Teresa
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium(II)-Catalyzed Oxidative Carbocyclization/Functionalization of Allenynes2013Licentiatavhandling, med artikler (Annet vitenskapelig)
    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.

  • 114.
    Bartholomeyzik, Teresa
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Deng, Youqian
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Selective Palladium-catalyzed oxidative carbocyclization of allenynes2013Inngår i: Abstracts of Papers of The American Chemical Society, American Chemical Society (ACS), 2013Konferansepaper (Annet vitenskapelig)
  • 115.
    Bartholomeyzik, Teresa
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Mazuela, Javier
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pendrill, Robert
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Deng, Youqian
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium-Catalyzed Oxidative Arylating Carbocyclization of Allenynes: Control of Selectivity and Role of H2O2014Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 53, nr 33, s. 8696-8699Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 116.
    Bartholomeyzik, Teresa
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pendrill, Robert
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Jiang, Tuo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Widmalm, Göran
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Complex Kinetics in a Palladium(II)-Catalyzed Oxidative Carbocyclization: Untangling of Competing Pathways, Pre-Catalyst Activation, and Product MixturesManuskript (preprint) (Annet vitenskapelig)
  • 117.
    Bartoszewicz, Agnieszka
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Building molecular complexity via tandem Ru-catalyzed reactions of allylic alcohols2009Licentiatavhandling, med artikler (Annet vitenskapelig)
  • 118.
    Bartoszewicz, Agnieszka
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Transition metal-catalysed hydrogen transfer processes for C-C and C-N bond formation: Synthetic studies and mechanistic investigations2012Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis focusses on synthetic studies and mechanistic investigations into reactions involving hydrogen-transfer processes.

    In the first part, the development of an efficient method for the synthesis of β-hydroxy ketones (aldols) and β-amino ketones (Mannich products) from allylic alcohols and aldehydes is described. These reactions use  Ru(η5-C5Ph5)(CO)2Cl as the catalyst. The reaction parameters were optimised in order to suppress the formation of undesired by-products. Neutral and mild reaction conditions enabled the synthesis of a variety of aldol products in up to 99% yield, with a good syn/anti ratio. The influence of the stereoelectronic properties of the catalyst on the reaction outcome was also studied. Based on the results obtained, a plausible reaction mechanism has been proposed, involving as the key steps the 1,4-addition of hydride to α,β-unsaturated ketones and the formation of ruthenium (Z)-enolates.

    In the second part of this thesis, a ruthenium-catalysed tandem isomerisation/C-H activation reaction is presented. A number of ruthenium complexes, phosphine ligands, and additives were evaluated in order to establish the optimal reaction conditions. It was found that the use of a stable ruthenium catalyst, Ru(PPh3)3Cl2, together with PtBu3 and HCO2Na resulted in an efficient tandem transformation. Using this procedure, a variety of ortho-alkylated ketones were obtained in excellent yields. Moreover, homoallylic alcohols could also be used as starting materials for the reaction, which further expands the substrate scope. Mechanistic investigations into the isomerisation part of the process were carried out.

    The last project described in the thesis deals with the design and preparation of novel bifunctional iridium complexes containing an N-(2-hydroxy-isobutyl)-N-Heterocyclic carbene ligand. These complexes were used as catalysts to alkylate amines using alcohols as latent electrophiles. The catalytic system developed here was found to be one of the most active systems reported to date, allowing the reaction to be performed at temperatures as low as 50 °C for the first time. A broad substrate scope was examined. Combined experimental and theoretical studies into the reaction mechanism are consistent with a metal-ligand bifunctional activity of the new catalyst.

  • 119.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Ahlsten, Nanna
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martin-Matute, Belen
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Enantioselective Synthesis of Alcohols and Amines by Iridium-Catalyzed Hydrogenation, Transfer Hydrogenation, and Related Processes2013Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 19, nr 23, s. 7274-7302Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The preparation of chiral alcohols and amines by using iridium catalysis is reviewed. The methods presented include the reduction of ketones or imines by using hydrogen (hydrogenations), isopropanol, formic acid, or formate (transfer hydrogenations). Also dynamic and oxidative kinetic resolutions leading to chiral alcohols and amines are included. Selected literature reports from early contributions to December 2012 are discussed.

  • 120.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    González Miera, Greco
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Marcos, Rocio
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Norrby, Per-Ola
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Mechanistic Studies on the Alkylation of Amines with Alcohols Catalyzed by a Bifunctional Iridium Complex2015Inngår i: ACS Catalysis, ISSN 2155-5435, E-ISSN 2155-5435, Vol. 5, nr 6, s. 3704-3716Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The mechanism of the N-alkylation of amines with alcohols catalyzed by an iridium complex containing an N-heterocyclic carbene (NHC) ligand with a tethered alcohol/alkoxide functionality was investigated by a combination of experimental and computational methods. The catalyst resting state is an iridium hydride species containing the amine substrate as a ligand, and decoordination of the amine, followed by coordination of the imine intermediate to the iridium center, constitute the rate-determining step (rds) of the catalytic process. The alcohol/alkoxide that is tethered to the NHC participates in every step of the catalytic cycle by accepting or releasing protons and forming hydrogen bonds with the reacting species. Thus, the iridium complex with the alcohol/alkoxide tethered to the N-heterocyclic carbene ligand acts as a bifunctional catalyst.

  • 121.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Jezowska, Martina M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Laymand, Kevin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Mobus, Juri
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of β-Hydroxy and β-Amino Ketones from Allylic Alcohols Catalyzed by Ru(η5-C5Ph5)(CO)2Cl2012Inngår i: European Journal of Inorganic Chemistry, ISSN 1434-1948, E-ISSN 1099-1948, nr 9, s. 1517-1530Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An efficient method for the synthesis of beta-hydroxy and beta-amino ketones from allylic alcohols catalyzed by Ru(5-C5Ph5)(CO)2Cl is described. The influence of the stereoelectronic properties of the catalyst on the reaction outcome has been studied. Optimization of the reaction conditions supressed the formation of undesired side products such as saturated ketones, benzyl alcohols, and a,beta-unsaturated ketones. Several aromatic and aliphatic allylic alcohols have been reacted with a large variety of aldehydes or imines to produce beta-hydroxy ketones or beta-amino ketones, respectively, in yields up to 99%. Based on experimental data, a mechanism via ruthenium alkoxides and ruthenium aldoxides is proposed. In addition, a C-bound ruthenium enolate has been characterized.

  • 122.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kalek, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Iodine-promoted silylation of alcohols with silyl chlorides. Synthetic and mechanistic studies2008Inngår i: Tetrahedron, ISSN 0040-4020, Vol. 64, nr 37, s. 8843-8850Artikkel i tidsskrift (Fagfellevurdert)
  • 123.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kalek, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of nucleoside phosphorothio-, phosphorodithio- and phophoroselenoate diesters via oxidative esterification of the corresponding H-phosphonate analogues2008Inngår i: Collection Symposium Series, Vol. 10, 2008, s. 219-223Konferansepaper (Annet vitenskapelig)
  • 124.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kalek, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Stawinski, Jacek
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    The case for the intermediacy of monomeric metaphosphate analogues during oxidation of H-phosphonothioate, H-phosphonodithioate, and H-phosphonoselenoate monoesters: mechanistic and synthetic studies2008Inngår i: The Journal of Organic Chemistry, ISSN 0022-3263, Vol. 73, nr 13, s. 5029-5038Artikkel i tidsskrift (Fagfellevurdert)
  • 125.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Livendahl, Madeleine
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Efficient synthesis of beta-hydroxy ketones from allylic alcohols by catalytic formation of ruthenium enolates2008Inngår i: Chemistry: a European Journal, ISSN 0947-6539, Vol. 14, nr 34, s. 10547-10550Artikkel i tidsskrift (Fagfellevurdert)
  • 126.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Livendahl, Madeleine
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of b-Hydroxy Ketones from Allylic Alcohols via Catalytic Formation of Ruthenium Enolates2008Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 14, nr 34, s. 10547-10550Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The most efficient Ru-catalyzed isomerization–aldol reaction from allylic alcohols has been achieved by using [η5-(Ph5Cp)Ru(CO)2Cl] as the catalyst. The bulky pentaphenylcyclopentadienyl ligand on the ruthenium atom prevents protonation at the oxygen of the Ru–enolate intermediate and completely suppresses the formation of unwanted ketone byproducts (see scheme). The domino transformation is as good as it can be: aldols are obtained in quantitative yields at ambient temperature.

  • 127.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Marcos, Rocio
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sahoo, Suman
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Inge, A. Ken
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Zou, Xiaodong
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    A Highly Active Bifunctional Iridium Complex with an Alcohol/Alkoxide-Tethered N-Heterocyclic Carbene for Alkylation of Amines with Alcohols2012Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 18, nr 45, s. 14510-14519Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    A series of new iridium(III) complexes containing bidentate N-heterocyclic carbenes (NHC) functionalized with an alcohol or ether group (NHC?OR, R=H, Me) were prepared. The complexes catalyzed the alkylation of anilines with alcohols as latent electrophiles. In particular, biscationic IrIII complexes of the type [Cp*(NHC-OH)Ir(MeCN)]2+2[BF4-] afforded higher-order amine products with very high efficiency; up to >99?% yield using a 1:1 ratio of reactants and 12.5 mol?% of Ir, in short reaction times (216 h) and under base-free conditions. Quantitative yields were also obtained at 50?degrees C, although longer reaction times (4860 h) were needed. A large variety of aromatic amines have been alkylated with primary and secondary alcohols. The reactivity of structurally related iridium(III) complexes was also compared to obtain insights into the mechanism and into the structure of possible catalytic intermediates. The IrIII complexes were stable towards oxygen and moisture, and were characterized by NMR, HRMS, single-crystal X-ray diffraction, and elemental analyses.

  • 128.
    Bartoszewicz, Agnieszka
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Building molecular complexity via tandem Ru-catalyzed isomerization/C-H activation2009Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 11, nr 8, s. 1749-1752Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A tandem isomerization/C-H activation of allylic alcohols was performed using a catalytic amount of RUCl(2)(PPh(3))(3). A variety of ortho alkylated ketones have been obtained in excellent yields. This tandem process relies on an in situ generation of a carbonyl functional group that directs the ortho C-H bond activation.

  • 129. Battistel, Marcos D.
    et al.
    Pendrill, Robert
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Widmalm, Göran
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Freedberg, Daron I.
    Direct Evidence for Hydrogen Bonding in Glycans: A Combined NMR and Molecular Dynamics Study2013Inngår i: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 117, nr 17, s. 4860-4869Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We introduce the abundant hydroxyl groups of glycans as NMR handle's and structural probes to expand the repertoire of tools for structure function studies on glycans in solution. To this end, we present the facile detection and assignment of hydroxyl groups in a Wide range of sample concentrations (0.5-1700 mM) and temperatures, ranging from -5 to 25 degrees C.,We then exploit this information to directly detect hydrogen bonds, well-known for their importance in molecular structural determination through NMR. Via HSQC-TOCSY, we were able to determine the directionality; of these hydrogen bonds in sucrose Furthermore, by means Of molecular dynamics simulations in conjunction with NMR, we establish that one Out of the three detected hydrogen bonds arises from intermolecular interactions. This finding may shed light on glycan glycan interactions and glycan recognition by proteins.

  • 130. Bejhed, Rebecca S.
    et al.
    Tian, Bo
    Eriksson, Kristofer
    Brucas, Rimantas
    Oscarsson, Sven
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Strömberg, Mattias
    Svedlindh, Peter
    Gunnarsson, Klas
    Magnetophoretic Transport Line System for Rapid On-Chip Attomole Protein Detection2015Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 31, nr 37, s. 10296-10302Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A lab-on-a-chip traveling wave magnetophoresis approach for sensitive and rapid protein detection is reported. In this method, a chip-based magnetic microarray comprising lines of micrometer-sized thin film magnetic elements was used to control the movement of magnetic beads (MBs). The MBs and the chip were functionalized, forming a sandwich-type assay. The MBs were transported across a detection area, and the presence of target molecules resulted in the immobilization of MBs within this area. Target quantification was accomplished by MB counting in the detection area using an optical microscope. In order to demonstrate the versatility of the microarray, biotinylated antiavidin was selected as the target protein. In this case, avidin-functionalized MBs and an avidin-functionalized detection area were used. With a total assay time of 1 to 1.5 h (depending on the labeling approach used), a limit of detection in the attomole range was achieved. Compared to on-chip surface plasmon resonance biodetection systems, our method has a larger dynamic range and is about a factor of 500 times more sensitive. Furthermore, our MB transportation system can operate in any chip-based biosensor platform, thereby significantly improving traditional biosensors.

  • 131.
    Belhomme, Marie-Charlotte
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Wang, Dong
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Szabó, Kálmán J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Formation of C(sp(3))-C(sp(3)) Bonds by Palladium Catalyzed Cross-Coupling of alpha-Diazoketones and Allylboronic Acids2016Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 18, nr 10, s. 2503-2506Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Palladium catalyzed cross-coupling of allylboronic acids with a-diazoketones was studied. The reaction selectively affords the linear allylic product. The reaction proceeds with formation of a new C(sp(3))-C(sp(3)) bond. The reaction was performed without an external oxidant, likely without the Pd-catalyst undergoing redox reactions.

  • 132. Bergenstråhle-Wohlert, Malin
    et al.
    Angles d'Ortoli, Thibault
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sjöberg, Nils A.
    Widmalm, Göran
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Wohlert, Jakob
    On the anomalous temperature dependence of cellulose aqueous solubility2016Inngår i: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 23, nr 4, s. 2375-2387Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The solubility of cellulose in water-based media is promoted by low temperature, which may appear counter-intuitive. An explanation to this phenomenon has been proposed that is based on a temperature-dependent orientation of the hydroxymethyl group. In this paper, this hypothesis is investigated using molecular dynamics computer simulations and NMR spectroscopy, and is discussed in conjunction with alternative explanations based on solvent–solute and solvent–solvent hydrogen bond formation respectively. It is shown that neither simulations nor experiments lend support to the proposed mechanism based on the hydroxymethyl orientation, whereas the two alternative explanations give rise to two distinct contributions to the hydration free energy of cellooligomers.

  • 133. Berggren, Gustav
    et al.
    Kaynak, Filiz Betul
    Anderlund, Magnus F.
    Eriksson, Lars
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi.
    Åkermark, Björn
    Institutionen för organisk kemi.
    Tetraethylammonium [12,12-diethyl-2,2,9,9-tetramethyl-1,4,7,10-tetraza-5,6-benzotridecane-3,8,11,13-tetra-one(4-)]oxidomanganate(V)2007Inngår i: Acta Crystallographica Section E, ISSN 1600-5368, Vol. E63, s. m2672-m2673Artikkel i tidsskrift (Fagfellevurdert)
  • 134. Berglund, Jennie
    et al.
    Angles d'Ortoli, Thibault
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Vilaplana, Francisco
    Widmalm, Göran
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bergenstråhle-Wohlert, Malin
    Lawoko, Martin
    Henriksson, Gunnar
    Lindström, Mikael
    Wohlert, Jakob
    A molecular dynamics study of the effect of glycosidic linkage type in the hemicellulose backbone on the molecular chain flexibility2016Inngår i: The Plant Journal, ISSN 0960-7412, E-ISSN 1365-313X, Vol. 88, nr 1, s. 56-70Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The macromolecular conformation of the constituent polysaccharides in lignocellulosic biomass influences their supramolecular interactions, and therefore their function in plants and their performance in technical products. The flexibility of glycosidic linkages from the backbone of hemicelluloses was studied by evaluating the conformational freedom of the φ and ψ dihedral angles using molecular dynamic simulations, additionally selected molecules were correlated with experimental data by NMR spectroscopy. Three types of β-(1→4) glycosidic linkages involving the monosaccharides (Glcp, Xylp and Manp) present in the backbone of hemicelluloses were defined. Different di- and tetrasaccharides with combinations of such sugar monomers from hemicelluloses were simulated and free energy maps of the φ - ψ space and hydrogen bonding patterns were obtained. The glycosidic linkage between Glc-Glc or Glc-Man (C-type) was the stiffest with mainly one probable conformation; the linkage from Man-Man or Man-Glc (M-type) was similar but with an increased probability for an alternative conformation making it more flexible, and the linkage between two Xyl-units (X-type) was the most flexible with two almost equally populated conformations. Glycosidic linkages of the same type showed essentially the same conformational space in both disaccharides and in the central region of tetrasaccharides. Different probabilities of glycosidic linkage conformations in the backbone of hemicelluloses can be directly estimated from the free energy maps, which to a large degree affect the overall macromolecular conformations of these polymers. The information gained contributes to an increased understanding of hemicelluloses’ function both in the cell wall and in technical products.

  • 135.
    Bermejo Gomez, Antonio
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Erbing, Elis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Batuecas, Maria
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Vazquez-Romero, Ana
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martin-Matute, Belen
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Iridium-Catalyzed Isomerization/Bromination of Allylic Alcohols: Synthesis of alpha-Bromocarbonyl Compounds2014Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 20, nr 34, s. 10703-10709Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    alpha-Brominated ketones and aldehydes, with two adjacent electrophilic carbon atoms, are highly valuable synthetic intermediates in organic synthesis, however, their synthesis from unsymmetrical ketones is very challenging, and current methods suffer from low selectivity. We present a new, reliable, and efficient method for the synthesis of alpha-bromocarbonyl compounds in excellent yields and with excellent selectivities. Starting from allylic alcohols as the carbonyl precursors, the combination of a 1,3-hydrogen shift catalyzed by iridium(III) with an electrophilic bromination gives alpha-bromoketones and aldehydes in good to excellent yields. The selectivity of the process is determined by the structure of the starting allylic alcohol; thus, alpha-bromoketones formally derived from unsymmetrical ketones can be synthesized in a straightforward and selective manner.

  • 136. Bermejo Góme, Antonio
    et al.
    Cortés González, Miguel A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Karolinska Intitutet, Sweden.
    Lübcke, Marvin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Karolinska Intitutet, Sweden.
    Johansson, Magnus J.
    Schou, Magnus
    Szabó, Kálmán J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Karolinska Intitutet, Sweden.
    Synthesis of trifluoromethyl moieties by late-stage copper (I) mediated nucleophilic fluorination2017Inngår i: Journal of fluorine chemistry, ISSN 0022-1139, E-ISSN 1873-3328, Vol. 194, s. 51-57Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The nucleophilic fluorination of bromodifluoromethyl derivatives mediated by the complex (PPh3)(3)CuF is described. Under the reaction conditions, different trifluoroacetates, trifluorolcetones, trifluoroarenes and trifluoroacetamides were obtained in good yields.

  • 137.
    Bermejo Gómez, Antonio
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Ahlsten, Nanna
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Platero-Prats, Ana E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of 4,5-disubstituted 2-aminothiazoles from a,b-unsaturated ketones: Preparation of 5-benzyl-4-methyl-2-aminothiazolium hydrochloride salt2014Inngår i: Organic Syntheses, ISSN 0078-6209, Vol. 91, s. 185-200Artikkel i tidsskrift (Fagfellevurdert)
  • 138.
    Bermejo Gómez, Antonio
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Karolinska Universitetssjukhuset, Sweden; Karolinska Institutet, Sweden.
    Cortés González, Miguel A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Karolinska Institutet, Sweden.
    Lübcke, Marvin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Karolinska Institutet, Sweden.
    Johansson, Magnus J.
    Halldin, Christer
    Szabó, Kálmán J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Karolinska Insitutet, Sweden.
    Schou, Magnus
    Efficient DBU accelerated synthesis of F-18-labelled trifluoroacetamides2016Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 52, nr 97, s. 13963-13966Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Nucleophilic F-18-fluorination of bromodifluoromethyl derivatives was performed using [F-18] Bu4NF in the presence of DBU(1,8-diazabicyclo[5.4.0]undec-7-ene). This novel procedure provided a diverse set of [F-18] trifluoroacetamides in good to excellent radiochemical conversions. A mechanism where DBU acts as organomediator in this transformation is proposed.

  • 139.
    Bermejo Gómez, Antonio
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Holmberg, Pär
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martin-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Transition metal-catalyzed redox isomerization of codeine and morphine in water2014Inngår i: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 4, nr 74, s. 39519-39522Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A water-soluble rhodium complex formed from commercially available [Rh(COD)(CH3CN)(2)]BF4 and 1,3,5-triaza-7-phosphaadamantane (PTA) catalyzes the isomerization of both codeine and morphine into hydrocodone and hydromorphone with very high efficiency. The reaction is performed in water, allowing isolation of the final products by simple filtration, which results in very high isolated yields. The reactions can be easily scaled up to 100 g.

  • 140.
    Bermejo-Gómez, Antonio
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Ahlsten, Nanna
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Martín-Matute, Belén
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Synthesis of 4,5-disubstituted 2-amino-1,3-thiazoles from α,β-unsaturated ketones: Preparation of 5-Benzyl-4-methyl-1,3-thiazol-2-amine hydrochlorideManuskript (preprint) (Annet vitenskapelig)
  • 141. Berner, Simon
    et al.
    Lidbaum, Hans
    Ledung, Greger
    Åhlund, John
    Nilson, Katharina
    Schiessling, Joachim
    Gelius, Ulrik
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Puglia, Carla
    Oscarsson, Sven
    Electronic and structural studies of immobilized thiol-derivatized cobalt porphyrins on gold surfaces2007Inngår i: Applied Surface Science, ISSN 0169-4332, Vol. 253, nr 18, s. 7540-7548Artikkel i tidsskrift (Fagfellevurdert)
  • 142.
    Bielawski, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Diaryliodonium Salts: Development of Synthetic Methodologies and α-Arylation of Enolates2011Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis describes novel reaction protocols for the synthesis of diaryliodonium salts and also provides an insight to the mechanism of α-arylation of carbonyl compounds with diaryliodonium salts.

     The first chapter gives a general introduction to the field of hypervalent iodine chemistry, mainly focusing on recent developments and applications of diaryliodonium salts.

    Chapter two describes the synthesis of electron-rich to electron-poor diaryliodonium triflates, in moderate to excellent yields from a range of arenes and iodoarenes.

    In chapter three, it is described that molecular iodine can be used together with arenes in a direct one-pot, three-step synthesis of symmetric diaryliodonium triflates. A large scale synthesis of bis(4-tert-butylphenyl)iodonium triflate is also described, controlled and verified by an external research group, further demonstrating the reliability of this methodology.

    The fourth chapter describes the development of a sequential one-pot synthesis of diaryliodonium salts from aryl iodides and boronic acids, furnishing symmetric and unsymmetric, electron-rich to electron-poor diaryliodonium tetrafluoroborates in moderate to excellent yields. This method was developed to overcome the regiochemical limitations imposed by the reaction mechanism in the protocols described in the preceding chapters.

    Chapter five describes a one-pot synthesis of heteroaromatic iodonium salts under similar conditions described in chapter two.

    The final chapter describes the reaction of enolates with chiral diaryliodonium salts or together with a phase transfer catalyst yielding racemic products. DFT calculations were performed, which revealed a low lying energy transition state (TS) between intermediates, which is believed to be responsible for the lack of selectivity observed in the experimental work. It is also proposed that a [2,3] rearrangement is preferred over a [1,2] rearrangement in the α-arylation of carbonyl compounds.

    The synthetic methodology described in this thesis is the most generally applicable, efficient and high-yielding to date for the synthesis of diaryliodonium salts, making these reagents readily available for various applications in synthesis.

  • 143.
    Bielawski, Marcin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Efficient and High-Yielding Routes to Diaryliodonium Salts2008Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis summarizes three novel and general reaction protocols for the synthesis of diaryliodonium salts. All protocols utilize mCPBA as oxidant and the acids used are either TfOH, to obtain triflate salts, or BF3•Et2O that gives the corresponding tetrafluoroborate salts in situ.

    Chapter two describes the reaction of various arenes and aryl iodides, delivering electron-rich and electron-deficient triflates in moderate to excellent yields.

    In chapter three, it is shown that the need of aryl iodides can be circumvented, as molecular iodine can be used together with arenes in a direct one-pot, three-step synthesis of symmetric diaryliodonium triflates.

    The final and fourth chapter describes the development of a sequential one-pot reaction from aryl iodides and boronic acids, delivering symmetric and unsymmetric, electron-rich and electron-deficient iodonium tetrafluoroborates in moderate to excellent yields. This protocol was developed to overcome mechanistic limitations existing in the protocols described in chapter two and three.

    The methodology described in this thesis is the most general, efficient and high-yielding existing up to date, making diaryliodonium salts easily available for various applications in synthesis.

  • 144.
    Bielawski, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Aili, David
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Regiospecific One-Pot Synthesis of Diaryliodonium Tetrafluoroborates from Arylboronic Acids and Aryl Iodides2008Inngår i: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 73, nr 12, s. 4602-4607Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Diaryliodonium salts have recently received considerable attention as mild arylation reagents in organic synthesis. This paper describes a regiospecific, sequential one-pot synthesis of symmetrical and unsymmetrical diaryliodonium tetrafluoroborates, which are the most popular salts in metal-catalyzed arylations. The protocol is fast and high-yielding and has a large substrate scope. Furthermore, the corresponding diaryliodonium triflates can conveniently be obtained via an in situ anion exchange.

  • 145.
    Bielawski, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Malmgren, Joel
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pardo, Leticia M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Wikmark, Ylva
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    One-Pot Synthesis and Applications of N-Heteroaryl Iodonium Salts2014Inngår i: ChemistryOpen, ISSN 2191-1363, Vol. 3, nr 1, s. 19-22Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An efficient one-pot synthesis of N-heteroaryl iodonium triflates from the corresponding N-heteroaryl iodide and arene has been developed. The reaction conditions resemble our previous one-pot syntheses, with suitable modifications to allow N-heteroaryl groups. The reaction time is only 30min, and no anion exchange is required. The obtained iodonium salts were isolated in a protonated form, these salts can either be employed directly in applications or be deprotonated prior to use. The aryl groups were chosen to induce chemoselective transfer of the heteroaryl moiety to various nucleophiles. The reactivity and chemoselectivity of these iodonium salts were demonstrated by selectively introducing a pyridyl moiety onto both oxygen and carbon nucleophiles in good yields.

  • 146.
    Bielawski, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Efficient one-pot synthesis of bis(4-tert-butylphenyl)iodonium triflate2009Inngår i: Organic Syntheses, ISSN 0078-6209, Vol. 86, s. 308-314Artikkel i tidsskrift (Fagfellevurdert)
  • 147.
    Bielawski, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    High-Yielding One-Pot Synthesis of Diaryliodonium Triflates from Arenes and Iodine or Aryl Iodides2007Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, nr 24, s. 2521-2523Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Unsymmetric and symmetric diaryliodonium triflates are synthesized from both electron-deficient and electron-rich substrates in a fast, high yielding, and operationally simple protocol employing arenes and aryl iodides or iodine.

  • 148.
    Bielawski, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Zhu, Mingzhao
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Efficient and General One-Pot Synthesis of Diaryliodonium Triflates: Optimization, Scope and Limitations2007Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 349, nr 17-18, s. 2610-2618Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Symmetrical and unsymmetrical diaryliodonium triflates have been synthesized from both electron-deficient and electron-rich arenes and aryl iodides with mCPBA and triflic acid. A thorough investigation of the optimization, scope and limitations has resulted in an improved one-pot protocol that is fast, high-yielding, and operationally simple. The reaction has been extended to the direct synthesis of symmetrical iodonium salts from iodine and arenes, conveniently circumventing the need for aryl iodides.

  • 149.
    Bielawski, Marcin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Zhu, Mingzhao
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Olofsson, Berit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Efficient and general one-pot synthesis of diaryliodonium triflates: scope and limitations2007Inngår i: SIS Report: The 10th Symposium on Iodine Science, Chiba University, Japan 2007, 2007, s. 19-22Konferansepaper (Annet vitenskapelig)
  • 150. Biosca, Maria
    et al.
    Paptchikhine, Alexander
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pàmies, Oscar
    Andersson, Pher G.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Diéguez, Montserrat
    Extending the Substrate Scope of Bicyclic P-Oxazoline/Thiazole Ligands for Ir-Catalyzed Hydrogenation of Unfunctionalized Olefins by Introducing a Biaryl Phosphoroamidite Group2015Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 21, nr 8, s. 3455-3464Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study identifies a series of Ir-bicyclic phosphoroamidite-oxazoline/thiazole catalytic systems that can hydrogenate a wide range of minimally functionalized olefins (including E-and Z-tri- and disubstituted substrates, vinylsilanes, enol phosphinates, tri- and disubstituted alkenylboronic esters, and alpha,beta-unsaturated enones) in high enantioselectivities (ee values up to 99%) and conversions. The design of the new phosphoroamidite-oxazoline/thiazole ligands derives from a previous successful generation of bicyclic N-phosphane-oxazoline/thiazole ligands, by replacing the N-phosphane group with a pi-acceptor biaryl phosphoroamidite moiety. A small but structurally important family of Ir-phosphoroamidite-oxazoline/thiazole precatalysts has thus been synthesized by changing the nature of the N-donor group (either oxazoline or thiazole) and the configuration at the biaryl phosphoroamidite moiety. The substitution of the N-phosphane by a phosphoroamidite group in the bicyclic N-phosphane-oxazoline/thiazole ligands extended the range of olefins that can be successfully hydrogenated.

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