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  • 1.
    Alamsetti, Santosh Kumar
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Persson, Andreas K. A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium-Catalyzed Intramolecular Hydroamination of Propargylic Carbamates and Carbamothioates2014Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 16, nr 5, s. 1434-1437Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An efficient and simple methodology was developed for the synthesis of oxazolidinones, oxazolidinthiones, imidazolidinthiones, and imidazolidinones from the corresponding propargylic starting materials using Pd(OAc)(2) and n-Bu4NOAc as catalysts in DCE at room temperature.

  • 2.
    Alamsetti, Santosh Kumar
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Persson, Andreas K. A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Jiang, Tuo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Scalable Synthesis of Oxazolones from Propargylic Alcohols through Multistep Palladium(II) Catalysis: beta-Selective Oxidative Heck Coupling of Cyclic Sulfonyl Enamides and Aryl Boroxines2013Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, nr 51, s. 13745-13750Artikkel i tidsskrift (Fagfellevurdert)
  • 3.
    Babu, Beneesh P.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Endo, Yoshinori
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Biomimetic Aerobic Oxidation of Amino Alcohols to Lactams2012Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 18, nr 37, s. 11524-11527Artikkel i tidsskrift (Fagfellevurdert)
  • 4.
    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)
  • 5.
    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)
  • 6.
    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.

  • 7.
    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)
  • 8.
    Bartholomeyzik, Teresa
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pendrill, Robert
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Lihammar, Richard
    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.
    Kinetics and Mechanism of the Palladium-Catalyzed Oxidative Arylating Carbocyclization of Allenynes2018Inngår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 140, nr 1, s. 298-309Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Pd-catalyzed C-C bond-forming reactions under oxidative conditions constitute a class of important and widely used synthetic protocols. This Article describes a mechanistic investigation of the arylating carbocyclization of allenynes using boronic acids and focuses on the correlation between reaction conditions and product selectivity. Isotope effects confirm that either allenic or propargylic C-H activation occurs directly after substrate binding. With an excess of H2O, a triene product is selectively formed via allenic C-H activation. The latter C-H activation was found to be turnover-limiting and the reaction zeroth order in reactants as well as the oxidant. A dominant feature is continuous catalyst activation, which was shown to occur even in the absence of substrate. Smaller amounts of H2O lead to mixtures of triene and vinylallene products, where the latter is formed via propargylic C-H activation. The formation of triene occurs only in the presence of ArB(OH)(2). Vinylallene, on the other hand, was shown to be formed by consumption of (ArBO)(3) as a first-order reactant. Conditions with sub-stoichiometric BF3 center dot OEt2 gave selectively the vinylallene product, and the reaction is first order in PhB(OH)(2). Both C-H activation and transmetalation influence the reaction rate. However, with electron-deficient ArB(OH)(2), C-H activation is turnover-limiting. It was difficult to establish the order of transmetalation vs C-H activation with certainty, but the results suggest that BF3 center dot OEt2 promotes an early transmetalation. The catalytically active species were found to be dependent on the reaction conditions, and H2O is a crucial parameter in the control of selectivity.

  • 9.
    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.

  • 10.
    Bogár, Krisztián
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    High-yielding metalloenzymatic dynamic kinetic resolution of fluorinated aryl alcohols2007Inngår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 48, nr 31, s. 5471-5474Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dynamic kinetic resolution (DKR) of various fluorinated aryl alcohols by a combination of lipase-catalyzed enzymatic resolution with in situ ruthenium-catalyzed alcohol racemization is described. (R)-Selective Candida antarctica lipase B (CALB) was employed for transesterification of different fluoroaryl alcohols in DKR reactions delivering the corresponding acetates in high yield (97%) with excellent enantiomeric excess (98%).

  • 11.
    Bogár, Krisztián
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Hoyos Vidal, Pilar
    Alcántara León, Andrés R.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Chemoenzymatic Dynamic Kinetic Resolution of Allylic Alcohols: A Highly Enantioselective Route to Acyloin Acetates2007Inngår i: Organic Letters, ISSN 1523-7060, E-ISSN 1523-7052, Vol. 9, nr 17, s. 3401-3404Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dynamic kinetic resolution (DKR) of a series of sterically hindered allylic alcohols has been conducted with Candida antarctica lipase B (CALB) and ruthenium catalyst 1. The optically pure allylic acetates obtained were subjected to oxidative cleavage to give the corresponding acylated acyloins in high yields without loss of chiral information.

  • 12.
    Bogár, Krisztián
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Krumlinde, Patrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bacsik, Zoltán
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Hedin, Niklas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Bäckvall, Jan E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Heterogenized Wilkinson's Catalyst for Transfer Hydrogenation of Carbonyl Compounds2011Inngår i: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, nr 23, s. 4409-4414Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Wilkinson’s catalyst [RhCl(PPh3)3] was heterogenized on common silica by the use of a grafting/anchoring technique. The immobilized catalyst showed high activity and selectivity in transfer hydrogenation reactions of a range of carbonyl compounds in 2-propanol. Reactions carried out in 2-propanol at reflux afforded the corresponding alcohols in high yields in short reaction times. The heterogeneous feature ofthe catalyst allows for easy recovery and efficient reuse in the same reaction up to 5 times without any detectible loss of catalytic activity.

  • 13. Bogár, Krisztián
    et al.
    Krumlinde, Patrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Hydrogenized Wilkinson´s Catalyst for Transfer Hydrogenation of Carbonyl CompoundsManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Combining the advantages of homogeneous and heterogeneous catalysis is possible by heterogenization of homogeneous transition metal complexes based on a grafting/anchoring technique. Wilkinson’s catalyst ((RhCl(PPh3)3) immobilized on common silica showed high activity and selectivity in transfer hydrogenation reactions of different carbonyl compounds in isopropanol. Reactions conducted at reflux in isopropanol afforded the corresponding carbinols in high yields in short reaction times. The heterogeneous feature of the catalyst allows easy recovery and efficient reuse in the same reaction up to 5 times without loss of catalytic activity.

  • 14.
    Bornschein, Christoph
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi. Universität Rostock, Germany.
    Gustafson, Karl P. J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Verho, Oscar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Beller, Matthias
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Evaluation of Fe and Ru Pincer-Type Complexes as Catalysts for the Racemization of Secondary Benzylic Alcohols2016Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 22, nr 33, s. 11583-11586Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Fe and Ru pincer-type catalysts are used for the racemization of benzylic alcohols. Racemization with the Fe catalyst was achieved within 30 minutes under mild reaction conditions, with a catalyst loading as low as 2 mol %. This reaction constitutes the first example of an iron-catalyzed racemization of an alcohol. The efficiency for racemization of the Fe catalyst and its Ru analogue was evaluated for a wide range of sec-benzylic alcohols. The commercially available Ru complex proved to be highly robust and even tolerated the presence of water in the reaction mixture.

  • 15.
    Borén, Linnéa
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Leijondahl, Karin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Dynamic Kinetic Asymmetric Transformation of 1,4-diols and Preparation of Trans-2,5-Disubstituted pyrrolidines2009Inngår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 50, nr 26, s. 3237-3240Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dynamic kinetic asymmetric transformation (DYKAT) of a series of 1,4-diols is carried out with Candida antarctica lipase B (CALB), Pseudomonas cepacia lipase II (PS-C II), and a ruthenium catalyst. A β-chloro-substituted 1,4-diol is successfully transformed into an optically pure 1,4-diacetate, which is a highly useful synthetic intermediate. The usefulness of the optically pure 1,4-diacetates is demonstrated by the synthesis of enantiopure 2,5-disubstituted pyrrolidines.

  • 16. Bratt, Emma
    et al.
    Verho, Oscar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Johansson, Magnus J.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    A General Suzuki Cross-Coupling Reaction of Heteroaromatics Catalyzed by Nanopalladium on Amino-Functionalized Siliceous Mesocellular Foam2014Inngår i: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 79, nr 9, s. 3946-3954Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Suzuki-Miyaura cross-coupling reactions of heteroaromatics catalyzed by palladium supported in the cavities of amino-functionalized siliceous mesocellular foam are presented. The nanopalladium catalyst effectively couples not only heteroaryl halides with boronic acids but also heteroaryl halides with boronate esters, potassium trifluoroborates, MIDA boronates, and triolborates, producing a wide range of heterobiaryls in good to excellent yields. Furthermore, the heterogeneous palladium nanocatalyst can easily be removed from the reaction mixture by filtration and recycled several times with minimal loss in activity. This catalyst provides an alternative, environmentally friendly, low-leaching process for the preparation of heterobiaryls.

  • 17.
    Bruneau, Alexandre
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Gustafson, Karl P. J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Yuan, Ning
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK). Swedish University of Agricultural Sciences, Sweden.
    Tai, Cheuk-Wai
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Persson, Ingmar
    Zou, Xiaodong
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Synthesis of Benzofurans and Indoles from Terminal Alkynes and Iodoaromatics Catalyzed by Recyclable Palladium Nanoparticles Immobilized on Siliceous Mesocellular Foam2017Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 23, nr 52, s. 12886-12891Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Herein, we report on the utilization of a heterogeneous catalyst, consisting of Pd nanoparticles supported on a siliceous mesocellular foam (Pd-0-AmP-MCF), for the synthesis of heterocycles. Reaction of o-iodophenols and protected o-iodoanilines with acetylenes in the presence of a Pd nanocatalyst produced 2-substituted benzofurans and indoles, respectively. In general, the catalytic protocol afforded the desired products in good to excellent yields under mild reaction conditions without the addition of ligands. Moreover, the structure of the reported Pd nanocatalyst was further elucidated with extended X-ray absorption fine-structure spectroscopy, and it was proven that the catalyst could be recycled multiple times without significant loss of activity.

  • 18.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Catalytic asymmetric synthesis via combined metal and enzyme catalysis2009Inngår i: 3rd Hellenic Symposium on Organic Synthesis, October 15-17, 2009, Athens, Greece: Abstracts of papers, Athens, 2009Konferansepaper (Annet vitenskapelig)
  • 19.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Modern Oxidation Methods2010Collection/Antologi (Annet vitenskapelig)
  • 20.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium- and ruthenium-catalyzed redox reactions in selective organic synthesis2009Inngår i: Abstract of LOST II Symposium in honour of Prof. Alain Krief, March 18-20, 2009, Namur, Belgium, 2009Konferansepaper (Annet vitenskapelig)
  • 21.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pd- and Ru-catalyzed redox reactions in catalysis. Application to the combination with enzyme catalysis2009Inngår i: Abstract of 42nd Jahrestreffen Deutscher Katalytiker, March 11-13, 2009, Weimar, Germany, 2009Konferansepaper (Annet vitenskapelig)
  • 22.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Preface2010Inngår i: Topics in catalysis, ISSN 1022-5528, E-ISSN 1572-9028, Vol. 53, nr 13-14, s. 831-831Artikkel i tidsskrift (Fagfellevurdert)
  • 23.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Recent advances in the combination of metal and enzyme catalysis2009Inngår i: Abstract of the 10th Netherlands Catalysis and Chemistry Conference (NCCC-X), March 2-4, 2009, Noordwijkerhout, the Netherlands, 2009Konferansepaper (Annet vitenskapelig)
  • 24.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Selective oxidation of amines and sulfides2010Inngår i: Modern Oxidation Methods / [ed] Jan-Erling Bäckvall, Weinheim: Wiley-VCH Verlag GmbH & Co. KGaA , 2010, 2, s. 277-313Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 25. Carballeira, José Daniel
    et al.
    Krumlinde, Patrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bocola, Marco
    Vogel, Andreas
    Reetz, Manfred T.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Directed evolution and axial chirality: optimization of the enantioselectivity of Pseudomonas aeruginosa lipase towards the kinetic resolution of a racemic allene2007Inngår i: Chemical Communications, ISSN 1359-7345, Vol. 20, s. 1913-1915Artikkel i tidsskrift (Fagfellevurdert)
  • 26.
    Chen, Hong
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för oorganisk kemi och strukturkemi.
    Deng, Youqian
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Yu, Zhengbao
    Zhao, Huishuang
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Yao, Qingxia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för oorganisk kemi och strukturkemi.
    Zou, Xiaodong
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för oorganisk kemi och strukturkemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sun, Junliang
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    3D Open-Framework Vanadoborate as a Highly Effective Heterogeneous Pre-catalyst for the Oxidation of Alkylbenzenes2013Inngår i: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 25, nr 24, s. 5031-5036Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Three three-dimensional (3D) open-framework vanadoborates, denoted as SUT-6-Zn, SUT-6-Mn, and SUT-6-Ni, were synthesized using diethylenetriamine as a template. SUT-6-Zn, SUT-6-Mn, and SUT-6-Ni are isostructural and built from (VO)(12)O-6 B18O36(OH)(6) clusters bridged by ZnO5, MnO6, and NiO6 polyhedra, respectively, to form the 3D frameworks. SUT-6 is the first vanadoborate with a 3D framework. The framework follows a semiregular hxg net topology with a 2-fold interpenetrated diamond-like channel system. The amount of template used in the synthesis played an important role in the dimensionality of the resulting vanadoborate structures. A small amount of diethylenetriamine led to the formation of this first 3D vanadoborate framework, while an increased amount of diethylenetriamine resulted in vanadoborates with zero-dimensional (0D) and one-dimensional (1D) structures. SUT-6-Zn was proved to be an efficient heterogeneous precatalyst for the oxidation of alkylbenzenes.

  • 27. Cotton, Hanna K.
    et al.
    Norinder, Jakob
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Screening of Ligands in the Asymmetric Metallocenethiolatocopper(I)-Catalyzed Allylic Substitution with Grignard Reagents2006Inngår i: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 62, nr 24, s. 5632-5640Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Screening of metallocenethiolate ligands for copper(I)-catalyzed substitution of allylic acetates with Grignard reagents has been carried out. The previously used ligand, lithium (R,Sp)-2-(1-dimethylaminoethyl)ferrocenylthiolate (4a), possessing both central and planar chirality, was the starting point for the screening. It was found that the diastereomeric ligand lithium (R,Rp)-2-(1-dimethylaminoethyl)ferrocenylthiolate (4b) exhibiting reversed planar chirality gave increased enantioselectivity in the allylic substitution, at least when cinnamyl acetate was used as a substrate. The ruthenocene-based ligand lithium (R,Sp)-2-(1-dimethylaminoethyl)ruthenocenylthiolate (4c) gave an enhanced reaction rate, but lower chiral induction. The use of disulfide bis[(R,Sp)-2-(1-dimethylaminoethyl)ferrocenyl]disulfide (7a) as a ligand precursor worked well but resulted in lower enantioselectivity.

  • 28.
    Csjernyik, Gábor
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bogár, Krisztián
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    New Efficient Ruthenium Catalysts for Racemization of Alcohols at Room Temperature2004Inngår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 45, nr 36, s. 6799-6802Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    5-Pentaphenylcyclopentadienyl)RuCl(CO)2 was found to catalyze efficiently the racemization of chiral alcohols such as (S)-1-phenylethanol, (S)-1-phenylpropan-2-ol, (S)-4-phenylbutan-2-ol and (S)-4-methoxy-1-phenylethanol at room temperature in the presence of a base. The catalytic activity of three other Ru(II) complexes was also investigated. The effects of halide and solvent were studied as well.

  • 29.
    Deng, Youqian
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bartholomeyzik, Teresa
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Persson, Andreas K. A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sun, Junliang
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium-Catalyzed Oxidative Arylating Carbocyclization of Allenynes2012Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 51, nr 11, s. 2703-2707Artikkel i tidsskrift (Fagfellevurdert)
  • 30.
    Deng, Youqian
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium-Catalyzed Oxidative Acyloxylation/Carbocyclization of Allenynes2013Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, nr 11, s. 3217-3221Artikkel i tidsskrift (Fagfellevurdert)
  • 31.
    Deng, Youqian
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Persson, Andreas K. A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Palladium-Catalyzed Oxidative Carbocyclizations2012Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 18, nr 37, s. 11498-11523Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Palladium-catalyzed oxidative carboncarbon bond-forming annulations, that is, carbocyclization reactions, have recently emerged as efficient and atom-economical routes to carbo- and heterocycles, whereby less functionalized substrates and fewer synthetic steps are needed to obtain a target molecule compared with traditional non-oxidative carboncarbon bond-forming reactions. In this review, the synthetic efforts in palladium-catalyzed oxidative carbocyclization reactions are summarized.

  • 32.
    Deng, Youqian
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Teresa, Bartholomeyzik
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Control of Selectivity in Palladium-Catalyzed Oxidative Carbocyclization/Borylation of Allenynes2013Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, nr 24, s. 6283-6287Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 33.
    Deska, Jan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Enzymatic kinetic resolution of primary allenic alcohols. Application to the total synthesis and stereochemical assignment of striatisporolide A2009Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 7, nr 17, s. 3379-3381Artikkel i tidsskrift (Fagfellevurdert)
  • 34.
    Deska, Jan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    del Pozo Ochoa, Carolina
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Chemoenzymatic dynamic kinetic resolution of axially chiral allenes2010Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 16, nr 15, s. 4447-4451Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dimeric palladium bromide complexes bearing monodentate N-heterocyclic carbene ligands have been identified as efficient catalysts for the chemoselective racemization of axially chiral allenyl alcohols. In combination with porcine pancreatic lipase as biocatalyst, a dynamic kinetic resolution has been developed, giving access to optically active allenes in good yield and high enantiomeric purity (

  • 35. Dorange, Ismet
    et al.
    Löfstedt, Joakim
    Franzén, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Närhi, Katja
    Bäckvall, Jan E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Allenes as Carbon Nucleophiles in Intramolecular Attack on (π-1,3-diene)Palladium Complexes: Evidence for trans-Carbopalladation of the 1,3-Diene2003Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 9, nr 14, s. 3445-3449Artikkel i tidsskrift (Fagfellevurdert)
  • 36.
    Endo, Yoshinori
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Aerobic Lactonization of Diols by Biomimetic Oxidation2011Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 17, nr 45, s. 12596-12601Artikkel i tidsskrift (Fagfellevurdert)
  • 37.
    Endo, Yoshinori
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Biomimetic Oxidative Coupling of Benzylamines and 2-Aminophenols: Synthesis of Benzoxazoles2012Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 18, nr 43, s. 13609-13613Artikkel i tidsskrift (Fagfellevurdert)
  • 38.
    Engelmark Cassimjee, Karim
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kadow, Maria
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Wikmark, Ylva
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Svedendahl Humble, Maria
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Rothstein, M. L.
    Rothstein, D. M.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    A general protein purification and immobilization method on controlled porosity glass: biocatalytic applications2014Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 50, nr 65, s. 9134-9137Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A general combined purification and immobilization method to facilitate biocatalytic process development is presented. The support material, EziG (TM), is based on controlled porosity glass (CPG) or polymer-coated versions thereof (HybCPG) and binds protein affinity tags. Biocatalytic reactions in aqueous and organic media with seven enzymes of biocatalytic interest are shown.

  • 39.
    Engström, Karin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Johnston, Eric V.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Verho, Oscar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Gustafson, Karl P. J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Shakeri, Mozaffar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Tai, Cheuk-Wai
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Co-immobilization of an Enzyme and a Metal into the Compartments of Mesoporous Silica for Cooperative Tandem Catalysis: An Artificial Metalloenzyme2013Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, nr 52, s. 14006-14010Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Surpassing nature: A hybrid catalyst in which Candida antarctica lipase B and a nanopalladium species are co-immobilized into the compartments of mesoporous silica is presented. The metal nanoparticles and the enzyme are in close proximity to one another in the cavities of the support. The catalyst mimics a metalloenzyme and was used for dynamic kinetic resolution of a primary amine in high yield and excellent enantioselectivity.

  • 40.
    Engström, Karin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Nyhlén, Jonas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sandström, Anders G.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Directed evolution of an enantioselective lipase with broad substrate scope for hydrolysis of α-substituted esters2010Inngår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 132, nr 20, s. 7038-7042Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A variant of Candida antarctica lipase A (CalA) was developed for the hydrolysis of α-substituted p-nitrophenyl esters by directed evolution. The E values of this variant for 7 different esters was 45−276, which is a large improvement compared to 2−20 for the wild type. The broad substrate scope of this enzyme variant is of synthetic use, and hydrolysis of the tested substrates proceeded with an enantiomeric excess between 95−99%. A 30-fold increase in activity was also observed for most substrates. The developed enzyme variant shows (R)-selectivity, which is reversed compared to the wild type that is (S)-selective for most substrates.

  • 41.
    Engström, Karin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Nyhlén, Jonas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Sandström, Anders G.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Enantioselective Kinetic Resolution of p-Nitrophenyl 2-Phenylpropanoate by a Variant of Candida antarctica Lipase A Developed by Directed Evolution2010Inngår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 132, nr 20, s. 7038-7042Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A variant of Candida antarctica lipase A (CalA) was developed for the hydrolysis of α-substituted p-nitrophenyl esters by directed evolution. The E values of this variant for 7 different esters was 45−276, which is a large improvement compared to 2−20 for the wild type. The broad substrate scope of this enzyme variant is of synthetic use, and hydrolysis of the tested substrates proceeded with an enantiomeric excess between 95−99%. A 30-fold increase in activity was also observed for most substrates. The developed enzyme variant shows (R)-selectivity, which is reversed compared to the wild type that is (S)-selective for most substrates.

  • 42.
    Engström, Karin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Shakeri, Mozaffar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Dynamic Kinetic Resolution of β-Amino Esters by a Heterogeneous System of a Palladium Nanocatalyst and Candida antarctica Lipase A2011Inngår i: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, nr 10, s. 1827-1830Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A dynamic kinetic resolution (DKR) of β-amino esters have been developed by the use of a heterogeneous racemization catalyst and an immobilized enzyme that accepts aromatic, heteroaromatic and aliphatic substrates. The reaction conditions were optimized to yield an efficient catalytic system without by-product formation. The products are obtained in 96–99 % ee and high yields

  • 43.
    Engström, Karin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Vallin, Michaela
    Hult, Karl
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kinetic resolution of diarylmethanols using a mutated variant of lipase CALB2012Inngår i: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 68, nr 37, s. 7613-7618Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An enzymatic kinetic resolution of diarylmethanols via acylation has been developed. This was achieved by the use of a mutated variant of CALB that accepts larger substrates compared to the wild type. By the use of diarylmethanols with two differently sized aryl groups, enantioselective transformations were achieved. A larger size-difference led to a higher enantioselectivity. In addition, substrates with electronically different aryl groups, such as phenyl and pyridyl, also gave an enantioselective reaction. The highest E value was observed with a substrate where steric and electronic effects were combined.

  • 44.
    Engström, Karin
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Vallin, Michaela
    Syrén, Per-Olof
    Hult, Karl
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Mutated variant of Candida antarctica lipase B in (S)-selective dynamickinetic resolution of secondary alcohols2011Inngår i: Organic and biomolecular chemistry, ISSN 1477-0520, E-ISSN 1477-0539, Vol. 9, nr 1, s. 81-82Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An (S)-selective dynamic kinetic resolution of secondaryalcohols, employing a mutated variant of Candida antarcticalipase B (CalB) gave products in 84–88% yield and in 90–97%ee.

  • 45.
    Ericsson, Daniel J.
    et al.
    1Department of Cell and Molecular Biology, Uppsala University, Biomedical Center.
    Kasrayan, Alex
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Johansson, Patrik
    1Department of Cell and Molecular Biology, Uppsala University, Biomedical Center.
    Bergfors, Terese
    1Department of Cell and Molecular Biology, Uppsala University, Biomedical Center.
    Sandström, Anders G.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Mowbray, Sherry L.
    Department of Molecular Biology, Swedish University of Agricultural Sciences, Biomedical Center.
    X-Ray structure of Candida antarctica lipase A shows a novel lid structure and a likely mode of interfacial activation2008Inngår i: Journal of Molecular Biology, ISSN 0022-2836, Vol. 376, nr 1, s. 109-119Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In nature, lipases (EC 3.1.1.3) catalyze the hydrolysis of triglycerides to form glycerol and fatty acids. Under the appropriate conditions, the reaction is reversible, and so biotechnological applications commonly make use of their capacity for esterification as well as for hydrolysis of a wide variety of compounds. In the present paper, we report the X-ray structure of lipase A from Candida antarctica, solved by single isomorphous replacement with anomalous scattering, and refined to 2.2-Å resolution. The structure is the first from a novel family of lipases. Contrary to previous predictions, the fold includes a well-defined lid as well as a classic α/β hydrolase domain. The catalytic triad is identified as Ser184, Asp334 and His366, which follow the sequential order considered to be characteristic of lipases; the serine lies within a typical nucleophilic elbow. Computer docking studies, as well as comparisons to related structures, place the carboxylate group of a fatty acid product near the serine nucleophile, with the long lipid tail closely following the path through the lid that is marked by a fortuitously bound molecule of polyethylene glycol. For an ester substrate to bind in an equivalent fashion, loop movements near Phe431 will be required, suggesting the primary focus of the conformational changes required for interfacial activation. Such movements will provide virtually unlimited access to solvent for the alcohol moiety of an ester substrate. The structure thus provides a basis for understanding the enzyme's preference for acyl moieties with long, straight tails, and for its highly promiscuous acceptance of widely different alcohol and amine moieties. An unconventional oxyanion hole is observed in the present structure, although the situation may change during interfacial activation

  • 46.
    Eriksson, Kristofer
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Gothelid, Emmanuelle
    Puglia, Carla
    Bäckvall, Jan-E.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Oscarsson, Sven
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Performance of a biomimetic oxidation catalyst immobilized on silica particles2013Inngår i: Journal of Catalysis, ISSN 0021-9517, E-ISSN 1090-2694, Vol. 303, s. 16-21Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A biomimetic oxidation catalyst, cobalt porphyrin with thiol linkers, was chemically conjugated to silica particles and utilized in the oxidation of hydroquinone to benzoquinone. The cobalt porphyrin/silica particle catalyst was characterized with Inductively Coupled Plasma (ICP) and X-ray Photoelectron Spectroscopy (XPS). The catalytic performance of the cobalt porphyrin molecules was compared to previous results for the same catalyst grafted to a gold surface and on silicon wafers. The measured catalytic activity, after background correction, was 100 times higher than that of its homogeneous counterpart, 10 times higher than that on a silicon wafer, and almost the same as that on a gold surface. The turnover frequency rates after 400 h are still comparable with initial rates reported for homogeneous porphyrins and salophens, whereas the use of particles as support increases the active surface area, which removes the limitations for scale-up associated with the previously used silicon wafers and gold surfaces.

  • 47. Eriksson, Kristofer L.E.
    et al.
    Chow, Winnie W.Y.
    Puglia, Carla
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Göthelid, Emmanuelle
    Oscarsson, Sven
    Performance of a biomimetic oxidation catalyst immobilized on silicon wafers: comparison with its gold congener2010Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 26, nr 21, s. 16349-16354Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    With the aim of extending the usefulness of an existing biomimetic catalytic system, cobalt porphyrin catalytic units with thiol linkers were heterogenized via chemical grafting to silicon wafers and utilized for the catalytic oxidation of hydroquinone to p-benzoquinone. Atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) were used to analyze the morphology and composition of the heterogeneous catalyst. The results of the catalytic oxidation of hydroquinone obtained with porphyrins grafted on silicon were compared with those obtained earlier with the same catalyst in homogeneous phase and immobilized on gold. It was found that the catalysis could run over 400 h, without showing any sign of deactivation. The measured catalytic activity is at least 10 times higher than that measured under homogeneous conditions, but also 10 times lower than that observed with the catalytic unit immobilized on gold. The reasons of this discrepancy are discussed in term of substrate influence and overlayer organization. The silicon-immobilized catalyst has potential as an advanced functional material with applications in oxidative heterogeneous catalysis of organic reactions, as it combines long-term relatively high activity with low cost.

  • 48.
    Eriksson, Kristofer
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Verho, Oscar
    Nyholm, Leif
    Oscarsson, Sven
    Bäckvall, Jan Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Electrochemical Preparation of Dispersed Gold Nanoparticles Supported in the Pores of Siliceous Mesocellular Foam: An Efficient Catalyst for Cycloisomerization of 4-Alkynoic Acids to LactonesManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    A versatile approach for the production of dispersed thiol-stabilized gold nanoparticles in the pores of siliceous mesocellular foam (MCF) is described and the thiol-stabilized gold nanoparticles were found to catalyze the cyclization of 4-pentynoic acids to lactones. The reported method is based on an electrochemical oxidation of a gold substrate generating oxidative Au(III) species which give rise to a surface-confined redox reaction yielding MCF supported Au(I)-thiolates. By reducing the MCF-S-Au(I) complex with sodium borohydride thiol-stabilized gold nanoparticles were obtained which were characterized with Transmission Electron Microscopy (TEM). The nanoparticles were found to be in the size of 1-8 nm. Inductive Coupled Plasma (ICP) analysis indicated an Au loading of 3 % (w/w) on the MCF. Further 0.5 mol% of the MCF-S-Au(0) solids were used to catalyze the cyclization reaction of 4-alkynoic acid under mild conditions with high selectivity (> 99%).

  • 49.
    Fransson, Ann-Britt L.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Borén, Linnéa
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Pàmies, Oscar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kinetic Resolution and Chemoenzymatic Dynamic Kinetic Resolution of Functionalized γ-Hydroxy Amides2005Inngår i: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 70, nr 7, s. 2582-2587Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An efficient kinetic resolution of racemic gamma-hydroxy amides 1 was performed via Pseudomas cepacia lipase (PS-C)-catalyzed transesterification. The enzyme PS-C tolerates both variation in the chain length and different functionalities giving good to high enantioselectivity (E values of up to > 250). The combination of enzymatic kinetic resolution with a ruthenium-catalyzed racemization led to a dynamic kinetic resolution. The use of 2,4-dimethyl-3-pentanol as a hydrogen source to suppress ketone formation in the dynamic kinetic resolution yields the corresponding acetates in good yield and good to high enantioselectivity (ee's up to 98%). The synthetic utility of this procedure was illustrated by the practical synthesis of the versatile intermediate gamma-lactone (R)-5-methyltetrahydrofuran-2-one.

  • 50.
    Fransson, Ann-Britt L.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Xu, Yongmei
    Leijondahl, Karin
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Enzymatic Resolution, Desymmetrization and Dynamic Kinetic Asym-metric Transformation of 1,3-Cycloalkanediols2006Inngår i: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 71, nr 17, s. 6309-6316Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An efficient desymmetrization of cis-1,3-cyclohexanediol to (1S,3R)-3-(acetoxy)-1-cyclohexanol ((R,S)-2a) was performed via Candida antarctica lipase B (CALB)-catalyzed transesterification, in high yield (up to 93%) and excellent enantioselectivity (ee's up to >99.5%). (R,R)-Diacetate ((R,R)-3a) was obtained in a DYKAT process at room temperature from (1S,3R)-3-acetoxy-1-cyclohexanol ((R,S)-2a), in a high trans/cis ratio (91:9) and in excellent enantioselectivity of >99%. Metal- and enzyme-catalyzed dynamic transformation of cis/trans-1,3-cyclohexanediol using PS-C gave a high diastereoselectivity for cis-diacetate (cis/trans = 97:3). The (1R,3S)-3-acetoxy-1-cyclohexanol (ent-(R,S)-2a) was obtained from cis-diacetate by CALB-catalyzed hydrolysis in an excellent yield (97%) and selectivity (>99% ee). By deuterium labeling it was shown that intramolecular acyl migration does not occur in the transformation of cis-monoacetate to the cis-diacetate.

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