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  • 1.
    Afewerki, Samson
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Alimohammadzadeh, Rana
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Henshaw Osong, Sinke
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Tai, Cheuk-Wai
    The Arrhenius Laboratory, Stockholm University.
    Engstrand, Per
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Eco-friendly design for scalable direct fabrication of nanocelluloseManuskript (preprint) (Annet vitenskapelig)
  • 2.
    Afewerki, Samson
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Alimohammadzadeh, Rana
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Osong, Sinke H.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Tai, Cheuk-Wai
    The Arrhenius Laboratory, Stockholm University.
    Engstrand, Per
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Sustainable Design for the Direct Fabrication and Highly Versatile Functionalization of Nanocelluloses2017Inngår i: Global Challenges, ISSN 2056-6646, Vol. 1, nr 7, artikkel-id 1700045Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study describes a novel sustainable concept for the scalable direct fabrication and functionalization of nanocellulose from wood pulp with reduced energy consumption. A central concept is the use of metal-free small organic molecules as mediators and catalysts for the production and subsequent versatile surface engineering of the cellulosic nanomaterials via organocatalysis and click chemistry. Here, “organoclick” chemistry enables the selective functionalization of nanocelluloses with different organic molecules as well as the binding of palladium ions or nanoparticles. The nanocellulosic material is also shown to function as a sustainable support for heterogeneous catalysis in modern organic synthesis (e.g., Suzuki cross-coupling transformations in water). The reported strategy not only addresses obstacles and challenges for the future utilization of nanocellulose (e.g., low moisture resistance, the need for green chemistry, and energy-intensive production) but also enables new applications for nanocellulosic materials in different areas.

  • 3.
    Afewerki, Samson
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Breistein, Palle
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Pirttilä, Kristian
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Deiana, Luca
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden.
    Dziedzic, Pawel
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden.
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Catalytic Enantioselective beta-Alkylation of alpha,beta-Unsaturated Aldehydes by Combination of Transition-Metal- and Aminocatalysis: Total Synthesis of Bisabolane Sesquiterpenes2011Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 17, nr 32, s. 8784-8788Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Branching out! The first co-catalytic enantioselective (up to 98:2 e.r.) β-alkylation of α,β-unsaturated aldehydes by combination of simple chiral amine and copper catalysts provides β-branched aldehydes in a one-pot protocol (see scheme). The methodology was applied to the short total syntheses of bisabolane sesquiterpenes (S)-(+)-curcumene, (E)-(S)-(+)-3- dehydrocurcumene and (S)-(+)-tumerone. © 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  • 4.
    Afewerki, Samson
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm Univ, Arrhenius Lab, Berzelii Ctr EXSELENT, Stockholm.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm Univ, Arrhenius Lab, Berzelii Ctr EXSELENT, Stockholm.
    Combinations of Aminocatalysts and Metal Catalysts: A Powerful Cooperative Approach in Selective Organic Synthesis2016Inngår i: Chemical Reviews, ISSN 0009-2665, E-ISSN 1520-6890, Vol. 116, nr 22, s. 13512-13570Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The cooperation and interplay between organic and metal catalyst Arninocatalysis systems is of utmost importance in nature and chemical synthesis. Here innovative and selective cooperative catalyst systems can be designed by combining two catalysts that complement rather than inhibit one another. This refined strategy can permit chemical transformations unmanageable by either of the catalysts alone. This review summarizes innovations and developments in selective organic synthesis that have used cooperative dual catalysis by combining simple aminocatalysts with metal catalysts. Considerable efforts have been devoted to this fruitful field. This emerging area employs the different activation modes of amine and metal catalysts as a platform to address challenging reactions. Here, aminocatalysis (e.g., enamine activation catalysis, iminium activation catalysis, single occupied molecular orbital (SOMO) activation catalysis, and photoredox activation catalysis) is employed to activate unreactive carbonyl substrates. The transition metal catalyst complements by activating a variety of substrates through a range of interactions (e.g., electrophilic pi-allyl complex formation, Lewis acid activation, allenylidene complex formation, photoredox activation, C-H activation, etc.), and thereby novel concepts within catalysis are created. The inclusion of heterogeneous catalysis strategies allows for "green" chemistry development, catalyst recyclability, and the more eco-friendly synthesis of valuable compounds.

  • 5.
    Afewerki, Samson
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Cooperative Lewis Acids and Aminocatalysis2017Inngår i: Chiral Lewis Acids in Organic Synthesis / [ed] J. Mlynarski, Wiley-Blackwell , 2017, s. 345-374Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    This chapter describes the cooperative strategy of combining metal catalyst activation with aminocatalysis, with a focus on the metal acting as a Lewis acid catalyst. It gives examples where the metal catalyst promotes the reactivity of different substrates by the formation of reactive intermediates. These intermediates can act either as electrophiles or nucleophiles, which in turn can couple with nucleophilic enamine or electrophilic iminium intermediates formed between the carbonyl compounds and aminocatalyst. The chemical transformation ensues via the merging of the enamine and π‐allyl‐Pd complex via asymmetric counteranion‐direct catalysis (ACDC). Subsequently, several groups reported different co‐catalytic systems and chemical strategies for the α‐allylic alkylation of aldehydes and ketones. Cordova and coworkers reported the first example where iminium activation catalysis is combined with metal catalyst activation cooperatively. The stratagem was demonstrated for the catalytic enantioselective conjugate silyl addition to α,β‐unsaturated aldehydes.

  • 6.
    Afewerki, Samson
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Enamine/Transition Metal Combined Catalysis: Catalytic Transformations Involving Organometallic Electrophilic Intermediates2019Inngår i: Topics in Current Chemistry, ISSN 2365-0869, Vol. 377, nr 6, artikkel-id 38Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The concept of merging enamine activation catalysis with transition metal catalysis is an important strategy, which allows for selective chemical transformations not accessible without this combination. The amine catalyst activates the carbonyl compounds through the formation of a reactive nucleophilic enamine intermediate and, in parallel, the transition metal activates a wide range of functionalities such as allylic substrates through the formation of reactive electrophilic π-allyl-metal complex. Since the first report of this strategy in 2006, considerable effort has been devoted to the successful advancement of this technology. In this chapter, these findings are highlighted and discussed. 

  • 7.
    Afewerki, Samson
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Guangning, Ma
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Highly enantioselective organo/metal cooperative catalysis for construction of spirocyclopentaneoxindoles2014Inngår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 248, artikkel-id 173-ORGNArtikkel i tidsskrift (Annet vitenskapelig)
  • 8.
    Afewerki, Samson
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Rydfjord, Jonas
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Breistein, Palle
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Direct Regiospecific and Highly Enantioselective Intermolecular α-Allylic Alkylation of Aldehydes By Combination of Transition Metal and amine Catalysts2012Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 18, nr 10, s. 2972-2977Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The first direct intermolecular regiospecific and highly enantioselective α-allylic alkylation of linear aldehydes by a combination of achiral bench-stable Pd 0 complexes and simple chiral amines as co-catalysts is disclosed. The co-catalytic asymmetric chemoselective and regiospecificα-allylic alkylation reaction is linked in tandem with in situ reduction to give the corresponding 2-alkyl alcohols with high enantiomeric ratios (up to 98:2 e.r.; e.r.=enantiomeric ratio). It is also an expeditious entry to valuable 2-alkyl substituted hemiacetals, 2-alkyl-butane-1,4-diols, and amines. The concise co-catalytic asymmetric total syntheses of biologically active natural products (e.g., Arundic acid) are disclosed. Go organic! Directintermolecular regiospecific and highly enantioselective α-allylic alkylation of linear aldehydes by a combination of achiral bench-stable Pd 0complexes and simple chiral amines as co-catalysts is disclosed (see scheme). Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  • 9.
    Afewerki, Samson
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm Univ, Berzelii Ctr EXSELENT, SE-10691 Stockholm, Sweden.
    Ma, Guangning
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Liu, Leifeng
    Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden .
    Sun, Junliang
    Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden .
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Department of Materials and Environmental Chemistry, Stockholm University, Stockholm, Sweden .
    Highly Enantioselective Control of Dynamic Cascade Transformations by Dual Catalysis: Asymmetric Synthesis of Polysubstituted Spirocyclic Oxindoles2015Inngår i: ACS Catalysis, ISSN 2155-5435, E-ISSN 2155-5435, Vol. 5, nr 2, s. 1266-1272Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The highly enantioselective (up to >99.5:0.5 er) synthesis of polysubstituted spirocyclic oxindoles with four new contiguous stereocenters, including the spiro all-carbon quaternary center, is disclosed. It is accomplished by the highly stereoselective control of a dynamic conjugate/intramolecular allylic alkylation relay sequence based on the synergistic cooperation of metal and chiral amine catalysts in which the careful selection of organic Nand, metal complex, and chiral amine is essential. The intermolecular C-C bond-forming step occurred only when both the metal and chiral amine catalysts were present.

  • 10.
    Afewerki, Samson
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap. Stockholm University, Stockholm.
    Wang, J. -X
    Jilin University, Changchun, China.
    Liao, W. -W
    Jilin University, Changchun, China.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap. Stockholm University, Stockholm.
    The Chemical Synthesis and Applications of Tropane Alkaloids2019Inngår i: Alkaloids: Chemistry and Biology, ISSN 1099-4831, Vol. 81, s. 151-233Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Tropanes are an important class of alkaloid natural products that are found in plants all over the world. These compounds can exhibit significant biological activity and are among the oldest known medicines. In the early 19th century, tropanes were isolated, characterized, and synthesized by notable chemical researchers. Their significant biological activities have inspired tremendous research efforts toward their synthesis and the elucidation of their pharmacological activity both in academia and in industry. In this chapter, which addresses the developments in this field since 1994, the focus is on the synthesis of these compounds, and several examples of sophisticated synthetic protocols involving both asymmetric and catalytic approaches are described. In addition, the structures of more than 100 new alkaloids are included as well as the applications and pharmacological properties of some tropane alkaloids. 

  • 11.
    Alimohammadzadeh, Rana
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Osong, Sinke H.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för kemiteknik.
    Abbaszad Rafi, Abdolrahim
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Dahlström, Christina
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för kemiteknik.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Cellulosic Materials: Sustainable Surface Engineering of Lignocellulose and Cellulose by Synergistic Combination of Metal-Free Catalysis and Polyelectrolyte Complexes2019Inngår i: Global Challenges, ISSN 2056-6646, Vol. 3, nr 7, artikkel-id 1970071Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In article number 1900018 by Armando Cordova and co‐workers, the novel combination of metal‐free catalysis and renewable polyelectrolyte complexes leads to synergistic surface engineering of lignocellulose and cellulose fibers derived from wood. This sustainable strategy allows for improvement and introduction of important properties such as strength (up to 100% in Z‐strength), water resistance, and fluorescence to the renewable fibers and cellulosic materials under eco‐friendly conditions.

  • 12.
    Alimohammadzadeh, Rana
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Osong, Sinke H.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för kemiteknik.
    Abbaszad Rafi, Abdolrahim
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Dahlström, Christina
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för kemiteknik.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Sustainable Surface Engineering of Lignocellulose and Cellulose by Synergistic Combination of Metal‐Free Catalysis and Polyelectrolyte Complexes2019Inngår i: Global Challenges, E-ISSN 2056-6646, Vol. 3, artikkel-id 1900018Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A sustainable strategy for synergistic surface engineering of lignocellulose and cellulose fibers derived from wood by synergistic combination of metal‐free catalysis and renewable polyelectrolyte (PE) complexes is disclosed. The strategy allows for improvement and introduction of important properties such as strength, water resistance, and fluorescence to the renewable fibers and cellulosic materials. For example, the “green” surface engineering significantly increases the strength properties (up to 100% in Z‐strength) of chemi‐thermomechanical pulp (CTMP) and bleached sulphite pulp (BSP)‐derived sheets. Next, performing an organocatalytic silylation with a nontoxic organic acid makes the corresponding lignocellulose and cellulose sheets hydrophobic. A selective color modification of polysaccharides is developed by combining metal‐free catalysis and thiol‐ene click chemistry. Next, fluorescent PE complexes based on cationic starch (CS) and carboxymethylcellulose (CMC) are prepared and used for modification of CTMP or BSP in the presence of a metal‐free catalyst. Laser‐scanning confocal microscopy reveals that the PE‐strength additive is evenly distributed on the CTMP and heterogeneously on the BSP. The fluorescent CS distribution on the CTMP follows the lignin distribution of the lignocellulosic fibers.

  • 13.
    Alimohammadzadeh, Rana
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Osong, Sinke H.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Dahlström, Christina
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Scalable Improvement of the Strength Properties of Chemimechanical Pulp Fibers by Eco-Friendly Catalysis2018Inngår i: IMPC 2018, Trondheim, Norway, 2018Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The sustainable improvement of the strength properties of chemimechanical pulp by eco-friendlycatalysis is disclosed. Significant research activities have been performed on the use of cationic starchand polyelectrolyte complexes for improving the strength properties of cellulose-based materials. Herewe apply an eco-friendly strategy based on catalysis for significantly improving the strength propertiesof sheets made from chemimechanical pulp (CTMP) and bleeched sulphite pulp (BSP) using sustainablepolyelectrolyte complexes as the strength additives and organocatalysis. This surface engineeringstrategy significantly increased the strength properties of the assembled sheets (up to 100% in the caseof Z-strength). We also developed a catalytic selective colour marking of the cationic potato starch (CS)and carboxymethylcellulose (CMC) in order to elucidated how the specific strength additives aredistributed on the sheets. It revealed that the strength additives were more evenly distributed on thesheets made from CTMP as compared to BSP sheets. This is most likely attributed to the presence oflignin in the former lignocellulosic material. It also contributes to the increase in strength (up to 100%,Z-strength) for the CTMP derived sheets. The selective colour marking method also revealed that morestrength additives had been bound to the pulps in the presence of the catalyst.

  • 14.
    Anderson, Mattias
    et al.
    AlbaNova Univ Ctr, KTH Royal Inst Technol, Sch Biotechnol, Div Ind Biotechnol, SE-10691 Stockholm, Sweden.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Berglund, Per
    AlbaNova Univ Ctr, KTH Royal Inst Technol, Sch Biotechnol, Div Ind Biotechnol, SE-10691 Stockholm, Sweden.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm Univ, Dept Organ Chem, Arrhenius Lab, SE-10691 Stockholm, Sweden.
    Total Synthesis of Capsaicin Analogues from Lignin-Derived Compounds by Combined Heterogeneous Metal, Organocatalytic and Enzymatic Cascades in One Pot2014Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 356, nr 9, s. 2113-2118Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The total synthesis of capsaicin analogues was performed in one pot, starting from compounds that can be derived from lignin. Heterogeneous palladium nanoparticles were used to oxidise alcohols to aldehydes, which were further converted to amines by an enzyme cascade system, including an amine transaminase. It was shown that the palladium catalyst and the enzyme cascade system could be successfully combined in the same pot for conversion of alcohols to amines without any purification of intermediates. The intermediate vanillyl-amine, prepared with the enzyme cascade system, could be further converted to capsaicin analogues without any purification using either fatty acids and a lipase, or Schotten-Baumann conditions, in the same pot. An aldol compound (a simple lignin model) could also be used as starting material for the synthesis of capsaicin analogues. Using l-alanine as organocatalyst, vanillin could be obtained by a retro-aldol reaction. This could be combined with the enzyme cascade system to convert the aldol compound to vanillylamine in a one-step one-pot reaction.

  • 15.
    Breistein, Palle
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Johansson, Jonas
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Lin, S.
    Deiana, Luca
    Sun, J.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    One-step catalytic enantioselective 5-hydroxy-α-quaternary proline synthesis: An asymmetric entry to highly functionalized α-quaternary proline derivativesManuskript (preprint) (Annet vitenskapelig)
  • 16.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Asymmetric Bifunctional Catalysis Using Heterobimetallic and Multimetallic Systems in Catalytic Asymmetric Conjugate Reactions2010Inngår i: Catalytic Asymmetric Conjugate Reactions, / [ed] Cordova, Weinheim: Wiley-VCH Verlagsgesellschaft, 2010, s. 169-189Kapittel i bok, del av antologi (Fagfellevurdert)
  • 17.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Combined heterogeneous metal/organic catalysts for eco-friendly synthesis2015Inngår i: Pure and Applied Chemistry, ISSN 0033-4545, E-ISSN 1365-3075, Vol. 87, nr 9-10, s. 1011-1019Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The interplay and synergistic cooperation between homogeneous and heterogeneous catalyst systems is of utmost importance in nature. It is also applied in chemical synthesis. Here, it can allow for new reactivity, which is not possible by the employment of a single catalyst, and promote the catalysis of multiple transformations in a one-pot sequence. This could overall lead to novel reactions and the development of sustainable chemistry. In this context, a versatile and broad synergistic strategy for the selective synthesis of valuable molecules with variable complexity and under eco-friendly conditions is disclosed. It is based on integrated heterogeneous metal/organo multiple relay catalysis, which is performed in a single reaction vessel, and allows for the assembly of complex molecules (e.g., heterocycles and carbocycles) with up to three quaternary stereocenters in a highly enantioselective fashion from simple alcohols and air/O-2.

  • 18.
    Cordova, Armando
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Alimohammadzadeh, Rana
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Sanhueza, Italo
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Tai, Cheuk-Wai
    Stockholm University, Stockholm.
    Osong, Sinke H.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för kemiteknik.
    Engstrand, Per
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för kemiteknik.
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för kemiteknik.
    A sustainable strategy for production and functionalization of nanocelluloses2019Inngår i: Pure and Applied Chemistry, ISSN 0033-4545, E-ISSN 1365-3075, Vol. 91, nr 5, s. 865-874Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A sustainable strategy for the neat production and surface functionalization of nanocellulose from wood pulp is disclosed. It is based on the combination of organocatalysis and click chemistry ("organoclick" chemistry) and starts with nanocellulose production by organic acid catalyzed hydrolysis and esterification of the pulp under neat conditions followed by homogenization. This nanocellulose fabrication route is scalable, reduces energy consumption and the organic acid can be efficiently recycled. Next, the surface is catalytically engineered by "organoclick" chemistry, which allows for selective and versatile attachment of different organic molecules (e.g. fluorescent probes, catalyst and pharmaceuticals). It also enables binding of metal ions and nanoparticles. This was exemplified by the fabrication of a heterogeneous nanocellulose-palladium nanoparticle catalyst, which is used for Suzuki cross-coupling transformations in water. The disclosed surface functionalization methodology is broad in scope and applicable to different nanocelluloses and cellulose based materials as well.

  • 19.
    Cordova, Armando
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Cihalova, Sylva
    Charles Univ Prague, Fac Sci, Dept Organ & Nucl Chem, Prague 12840, Czech Republic .
    Dziedzic, Pawel
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden.
    Vesely, Jan
    Charles Univ Prague, Fac Sci, Dept Organ & Nucl Chem, Prague 12840, Czech Republic .
    Asymmetric Aza-Morita-Baylis-Hillman-type reactions: The highly enantioselective reaction between unmodified α,β-unsaturated aldehydes and N-acyl imines by organo-co-catalysis2011Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, ISSN 1615-4150, Vol. 353, nr 7, s. 1096-1108Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The highly enantioselective organo-co-catalytic aza-Morita-Baylis-Hillman (MBH)-type reaction between N-carbamate-protected imines and alpha,beta-unsaturated aldehydes has been developed. The organic co-catalytic system of proline and 1,4-diazabicyclo[2.2.2]octane (DABCO) enables the asymmetricsynthesis of the corresponding N-Boc- and N-Cbz-protected beta-amino-alpha-alkylidene-aldehydes in good to high yields and up to 99% ee. In the case of aza-MBH-type addition of enals to phenylprop-2-ene-1-imines, the co-catalytic reaction exhibits excellent 1,2-selectivity. The organo-co-catalytic aza-MBH-type reaction can also be performed by the direct highly enantioselective addition of alpha,beta-unsaturated aldehydes to bench-stable N-carbamate-protected alpha-amidosulfones to give the corresponding beta-amino-alpha-alkylidene-aldehydes with up to 99% ee. The organo-co-catalytic aza-MBH-type reaction is also an expeditious entry to nearly enantiomerically pure beta-amino-alpha-alkylidene-amino acids and beta-amino-alpha-alkylidene-lactams (99% ee). The mechanism and stereochemistry of the chiral amine and DABCO co-catalyzed aza-MBH-type reaction are also discussed.

  • 20.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Catalytic Asymmetric Conjugate Reactions2010Collection/Antologi (Annet vitenskapelig)
    Abstract [en]

    Information from publisher:

    This unique and long-awaited handbook on this important topic in the hot field of stereoselective organic synthesis covers several types of nucleophiles. Top international authors deal with modern forms of achieving stereoselective conjugate additions based on the use of chiral ligands or asymmetric catalysis, such as P-N ligands, organocatalysis, domino reactions, Lewis acid and base catalysis. There is also a discussion of the employment of enantioselective conjugate addition transformations in total synthesis of important molecules. With its reliable and previously unpublished experimental procedures, this is a true source of high quality information.

  • 21.
    Córdova, Armando
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Breistein, Palle
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Deiana, Luca
    Zhao, Gui-Ling
    Dziedzic, Pawel
    Pirttilä, Kristian
    Lin, Shuangzheng
    TOC-Trends in Organic Chemistry: Selective Catalysis2010Konferansepaper (Annet vitenskapelig)
  • 22.
    Córdova, Armando
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    R., Rios
    Aziridine Formation: in C-N Bond Formation2012Inngår i: Comprehensive Chirality / [ed] Yamamoto, H.; Carreira, E. Eds, Oxford: Elsevier, 2012Kapittel i bok, del av antologi (Fagfellevurdert)
  • 23.
    Deiana, L.
    et al.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden .
    Ghisu, L.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden .
    Córdova, O.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden .
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Zhang, Renyun
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden .
    Efficient and highly enantioselective aerobic oxidation-michael- carbocyclization cascade transformations by integrated Pd(0)-CPG nanoparticle/chiral amine relay catalysis2014Inngår i: Synthesis (Stuttgart), ISSN 0039-7881, E-ISSN 1437-210X, Vol. 46, nr 10, s. 1303-1310Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of highly diastereo- and enantioselective aerobic oxidation-Michael-carbocyclization cascade transformations by integrated heterogeneous Pd(0)-CPG nanoparticle/chiral amine relay catalysis are disclosed. The heterogeneous Pd(0)-CPG nanoparticle catalysts were efficient for both the sequential aerobic oxidation and dynamic kinetic asymmetric Michael- carbocyclization transformations, resulting in 1) oxidation of a variety of allylic alcohols to enals and 2) formation of cyclopentenes containing an all-carbon quaternary stereocenter in good to high yields with up to 20:1 dr and 99.5:0.5 er. © Georg Thieme Verlag Stuttgart.New York.

  • 24. Deiana, L
    et al.
    Zhao, G-L
    Lin, S
    Dziedzic, P
    Zhang, Q
    Leijonmarck, H
    Còrdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Organocatalytic enantioselective aziridination of α-substituted α,β-unsaturated aldehydes: Asymmetric synthesis of terminal aziridines2010Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 352, nr 18, s. 3201-3207Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The first example of a highly enantioselective organocatalytic aziridination of α-substituted α,β-unsaturated aldehydes is presented. The reaction is catalyzed by simple chiral amines and gives access to highly functional terminal azirdines containing an α-tertiary amine stereocenter in high yields and enantiomeric ratios (95.5:4.5-98:2)

  • 25.
    Deiana, Luca
    et al.
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Palo-Nieto, Carlos
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Verho, Oscar
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Johnston, Eric V
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Highly Enantioselective Cascade Transformations by Merging Heterogeneous Transition Metal Catalysis with Asymmetric Aminocatalysis2012Inngår i: Scientific reports, ISSN 2045-2322, Vol. 2, s. Art. no. 851-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The concept of combining heterogeneous transition metal and amine catalysis for enantioselective cascade reactions has not yet been realized. This is of great advantage since it would allow for the recycling of expensive and non-environmentally friendly transition metals. We disclose that the use of a heterogeneous Pd-catalyst in combination with a simple chiral amine co-catalyst allows for highly enantioselective cascadetransformations. The preparative power of this process has been demonstrated in the context of asymmetric cascade Michael/carbocyclizationtransformations that delivers cyclopentenes bearing an all carbon quaternary stereocenters in high yields with up to 30:1 dr and 99% ee. Moreover, a variety of highly enantioselective cascade hetero-Michael/ carbocyclizations were developed for the one-pot synthesis of valuable dihydrofurans and pyrrolidines (up to 98% ee) by using bench-stable heterogeneous Pd and chiral amines as co-catalysts. © 2012 Macmillan Publishers Limited. All rights reserved.

  • 26.
    Deiana, Luca
    et al.
    Stockholm Univ, S-10691 Stockholm, Sweden.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm Univ, S-10691 Stockholm, Sweden.
    Nieto, Carlos Palo
    Stockholm Univ, S-10691 Stockholm, Sweden.
    Jiang, Yan
    Stockholm Univ, S-10691 Stockholm, Sweden.
    Johnston, Eric
    Stockholm Univ, S-10691 Stockholm, Sweden.
    Verho, Oscar
    Stockholm Univ, S-10691 Stockholm, Sweden.
    Combined multistep heterogeneous transition metal catalysis and aminocatalysis for asymmetric cascade reactions2013Inngår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 245, s. Meeting abstract 147-ORGN-Artikkel i tidsskrift (Annet vitenskapelig)
  • 27.
    Deiana, Luca
    et al.
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Dziedzic, Pawel
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Zhao, Gui-Ling
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Vesely, Jan
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Ibrahem, Ismail
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Rios, Ramon
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden .
    Sun, Junliang
    Stockholm Univ, Arrhenius Lab, Dept Struct Chem, S-10691 Stockholm, Sweden.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik. Stockholm Univ, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden.
    Catalytic Asymmetric Aziridination of alpha,beta-Unsaturated Aldehydes2011Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 17, nr 28, s. 7904-7917Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The development, scope, and application of the highly enantioselective organocatalytic aziridination of α,β-unsaturated aldehydes is presented. The aminocatalytic azirdination of α,β-unsaturated aldehydes enables the asymmetric formation of β-formyl aziridines with up to >19:1 d.r. and 99 % ee. The aminocatalytic aziridination of α-monosubstituted enals gives access to terminal α-substituted-α-formyl aziridines in high yields and up to 99 % ee. In the case of the organocatalytic aziridination of disubstituted α,β-unsaturated aldehydes, the transformations were highly diastereo- and enantioselective and give nearly enantiomerically pure β-formyl-functionalized aziridine products (99 % ee). A highly enantioselective one-pot cascade sequence based on the combination of asymmetric amine and N-heterocyclic carbene catalysis (AHCC) is also disclosed. This one-pot three-component co-catalytic transformation between α,β-unsaturated aldehydes, hydroxylamine derivatives, and alcohols gives the corresponding N-tert-butoxycarbonyl and N-carbobenzyloxy-protected β-amino acid esters with ee values ranging from 92-99 %. The mechanisms and stereochemistry of all these catalytic transformations are also discussed.

  • 28.
    Deiana, Luca
    et al.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden.
    Ghisu, Lorenza
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Verho, Oscar
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden.
    Johnston, Eric V.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden.
    Hedin, Niklas
    Berzelii Center EXSELENT, Stockholm University, SE-106 91 Stockholm, Sweden.
    Bacsik, Zoltan
    Department of Materials and Environmental Chemistry, Stockholm University, Stockholm SE-106 91, Sweden .
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden .
    Enantioselective Heterogeneous Synergistic Catalysis for Asymmetric Cascade Transformations2014Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 356, nr 11-12, s. 2485-2492Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A modular design for a novel heterogeneous synergistic catalytic system, which simultaneously activates the electrophile and nucleophile by the combined activation modes of a separate metal and non-metal catalyst, for asymmetric cascade transformations on a solid surface is disclosed. This modular catalysis strategy generates carbocycles (up to 97.5: 2.5 er) as well as spirocyclic oxindoles (97.5: 2.5 to > 99: 0.5 er), containing all-carbon quaternary centers, in a highly enantioselective fashion via a one-pot dynamic relay process.

  • 29.
    Deiana, Luca
    et al.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Jiang, Yan
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Palo-Nieto, Carlos
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Incerti-Pradillos, Celia A.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Verho, Oscar
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Tai, Cheuk-Wai
    Department of Materials and Environmental Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden .
    Johnston, Eric V.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Cordova, Armando
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691 Stockholm, Sweden.
    Combined Heterogeneous Metal/Chiral Amine: Multiple Relay Catalysis for Versatile Eco-Friendly Synthesis2014Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 53, nr 13, s. 3447-3451Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Herein is described a versatile and broad synergistic strategy for expansion of chemical space and the synthesis of valuable molecules (e.g. carbocycles and heterocycles), with up to three quaternary stereocenters, in a highly enantioselective fashion from simple alcohols (31examples, 95:5 to >99.5:0.5 e.r.) using integrated heterogeneous metal/chiral amine multiple relay catalysis and air/O-2 as the terminal oxidant. A novel highly 1,4-selective heterogeneous metal/amine co-catalyzed hydrogenation of enals was also added to the relay catalysis sequences.

  • 30. Deiana, Luca
    et al.
    Zhao, Gui-Ling
    Dziedzic, Pawel
    Rios, Ramon
    Vesely, Jan
    Ekström, Jesper
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    One-pot highly enantioselective catalytic Mannich-type reactions between aldehydes and stable a-amido sulfones: Asymmetric synthesis of b-amino aldehydes and b-amino acids2010Inngår i: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 51, nr 2, s. 234-237Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A highly enantioselective catalytic route to carbamate- and benzoate-protected β-amino aldehydes and β-amino acids is presented. The amino acid-catalyzed one-pot asymmetric reaction between unmodified aldehydes and α-amido sulfones gives the corresponding β-amino compounds with up to 95:5 dr and 97–>99% ee.

  • 31.
    Deiana, Luca
    et al.
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden.
    Zhao, Gui-Ling
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden.
    Leijonmarck, Hans
    Univ Stockholm, Arrhenius Lab, Dept Organ Chem, S-10691 Stockholm, Sweden.
    Sun, Junliang
    Univ Stockholm, Arrhenius Lab, Dept Struct Chem, S-10691 Stockholm, Sweden.
    Lehmann, Christian W
    Max Planck Inst Kohlenforsch, D-45470 Mulheim, Germany.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Direct Catalytic Asymmetric Synthesis of Pyrazolidine Dervates2012Inngår i: ChemistryOpen, ISSN 2191-1363, Vol. 1, nr 3, s. 134-139Artikkel i tidsskrift (Fagfellevurdert)
  • 32.
    Hafrén, Jonas
    et al.
    Swedish University of Agricultural Sciences, Uppsala.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm University.
    Organoclick: Applied Eco-Friendly and Metal-Free Catalysis for Wood and Fiber Modifications2016Inngår i: Industrial Biorenewables: A Practical Viewpoint, John Wiley & Sons, 2016, s. 437-450Kapittel i bok, del av antologi (Annet vitenskapelig)
    Abstract [en]

    This chapter provides a brief background to the research area of organocatalysis with respect to wood and fiber modification. It focuses on some of the examples of industrially produced materials from the chemical company OrganoClick AB, which employ organocatalytic reactions for modification, and to add new or improved functionalities to wood and natural fiber materials. The biomimetic activation of organic compounds via fundamental activation mechanisms is key in our efforts to create new functionally modified wood or fiber materials. There has been extensive research on the cross-linking of polysaccharides. The most common methods apply inorganic acids as catalysts for the cross-linking of the polysaccharide chains with low-molecular cross-linking agents, which are actually not eco-friendly. The novel materials could be of interest for the printing- or cellulose-based packaging industries. The OrganoWood process is based on mimicking the natural fossilization process in which wood is slowly transformed into mineral.

  • 33.
    Ibrahem, Ismail
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Breistein, Palle
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    One-pot three-component catalytic asymmetric synthesis of homoallylboronates2012Inngår i: ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY. Vol 243, American Chemical Society (ACS), 2012, s. 889-INOR-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    1. A novel one-pot three-component catalytic enantioselective reaction between bis(pinacolato)diboron, enals and 2-(triphenylphosphoranylidene)acetate esters employing inexpensive bench stable Cu salts and simple chiral amine as co-catalysts is presented. The reaction proceeds via a tandem catalytic asymmetric conjugate borane addition/Wittig sequence where the b-boration step is 1,4-selective and gives the corresponding homoallylboronate products with high enantiomeric ratios (up to 97.5:2.5 er).

    2. The direct intermolecular regiospecific and highly enantioselective a-allylic alkylation of linear aldehydes by combination of achiral bench stable Pd(0) complexes and simple chiral amines as co-catalysts is disclosed. The co-catalytic asymmetric chemoselective and regiospecific a-allylic alkylation reaction is linked in tandem with in situ reduction to give the corresponding 2-alkyl alcohols with high enantiomeric ratios (up to 98:2 er). It is also an expeditious entry to valuable 2-alkyl substituted hemiacetals and 2-alkyl-butane-1,4-diols.

  • 34.
    Ibrahem, Ismail
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Breistein, Palle
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    One-Pot Three-Component Catalytic Enantioselective Synthesis of Homoallylboronates2011Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 50, nr 50, s. 12036-12041Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    No longer a simple bor(ation): The title reaction between bis(pinacolato)diboron, enals, and 2-(triphenylphosphoranylidene)acetates employing bench-stable copper salts and a simple chiral amine co-catalyst is presented. The reaction proceeds through a catalytic asymmetric conjugate borane addition/Wittig sequence wherein the β-boration step is 1,4-selective and gives the corresponding homoallylboronate products with high enantiomeric ratios.

  • 35.
    Ibrahem, Ismail
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Breistein, Palle
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    One-pot three-component highly selective synthesis of homoallylboronates by using metal-free catalysis2012Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 18, nr 17, s. 5175-5179Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Metal-free selectivity: The first metal-free one-pot three-component highly chemo- and regioselective catalytic synthesis of homoallylboranes using simple N-heterocyclic carbenes (NHC) and amines is presented. The catalytic reaction between B 2(pin) 2, α,β-unsaturated aldehydes and 2-(triphenylphosphoranylidene)acetate esters proceeds through a catalytic metal-free β-boration/Wittig cascade sequence (see scheme). © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  • 36.
    Ibrahem, Ismail
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Ma, Guangning
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Palladium/Chiral Amine Co-catalyzed Enantioselective beta-Arylation of alpha,beta-Unsaturated Aldehydes2013Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, nr 3, s. 878-882Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Palladium and a simple chiral amine are used as co-catalysts for the enantioselective conjugate addition of aryl boronic acids to α,β-unsaturated aldehydes (see scheme). The synthetic utility of this co-catalyzed reaction was demonstrated in the short total syntheses of (R)-(-)-curcumene and 4-aryl-2-ones. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  • 37.
    Ibrahem, Ismail
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Santoro, Stefano
    Stockholm Univ, Dept Organ Chem, Arrhenius Lab, SE-10691 Stockholm, Sweden.
    Himo, Fahmi
    Stockholm Univ, Dept Organ Chem, Arrhenius Lab, SE-10691 Stockholm, Sweden.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Enantioselective Conjugate Silyl Additions to alpha,beta-Unsaturated Aldehydes Catalyzed by Combination of Transition Metal and Chiral Amine Catalysts2011Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 353, nr 2-3, s. 245-252Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We report that transition metal-catalyzed nucleophilic activation can be combined with chiral amine-catalyzed iminium activation as exemplified by the unprecedented enantioselective conjugate addition of a dimethylsilanyl group to alpha,beta-unsaturated aldehydes. These reactions proceed with excellent 1,4-selectivity to afford the corresponding beta-silyl aldehyde products 3 in high yields and up to 97:3 er using inexpensive bench stable copper salts and simple chiral amine catalysts. The reaction can also generate a quaternary stereocenter with good enantioselectivity. Density functional calculations are performed to elucidate the reaction mechanism and the origin of enantioselectivity.

  • 38.
    Jiang, Liying
    et al.
    Stockholm Univ, Dept Analyt Chem, SE-10691 Stockholm, Sweden.
    Dziedzic, Pawel
    Stockholm Univ, Dept Organ Chem, SE-10691 Stockholm, Sweden.
    Spacil, Zdenek
    Stockholm Univ, Dept Analyt Chem, SE-10691 Stockholm, Sweden.
    Zhao, Gui-Ling
    Stockholm Univ, Dept Organ Chem, SE-10691 Stockholm, Sweden.
    Nilsson, Lennart
    Karolinska Inst, SE-17177 Stockholm, Sweden.
    Ilag, Leopold L.
    Stockholm Univ, Dept Analyt Chem, SE-10691 Stockholm, Sweden.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm Univ, Dept Organ Chem, SE-10691 Stockholm, Sweden.
    Abiotic synthesis of amino acids and self-crystallization under prebiotic conditions2014Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 4, s. Art. no. 6769-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Building on previous research on the origin and homochirality of life, this study focuses on analyses profiling important building blocks of life: the natural amino acids. The spark discharge variation of the iconic Miller experiment was performed with a reducing gas mixture of ammonia, methane, water and hydrogen. Amino acid analysis using liquid chromatography coupled with tandem mass spectrometry after pre-column derivatizaiton revealed the generation of several amino acids including those essential for life. Re-crystallization of the synthetic products and enantiomeric ratio analysis were subsequently performed. Results from liquid chromatography coupled with either fluorescent detector or tandem mass spectrometry after pre-column derivatization with chiral reagent revealed spontaneous and effective asymmetric resolution of serine and alanine. This work describes a useful analytical platform for investigation of hypotheses regarding the origin and homochirality of amino acids under prebiotic conditions. The formation of numerous amino acids in the electric discharge experiment and the occurrence of high enantiomeric ratios of amino acids in re-crystallization experiment give valuable implications for future studies in unraveling fundamental questions regarding origins and evolution of life.

  • 39.
    Jiang, Yan
    et al.
    Stockholm University, Stockholm.
    Deiana, Luca
    Stockholm University, Stockholm.
    Alimohammadzadeh, Rana
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm University, Stockholm.
    Liu, Leifeng
    Stockholm University, Stockholm.
    Sun, Junliang
    Stockholm University, Stockholm.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm University, Stockholm.
    Highly Diastereo- and Enantioselective Cascade Synthesis of Bicyclic Lactams in One-Pot2018Inngår i: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, Vol. 2018, nr 9, s. 1158-1164Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A versatile and highly stereoselective synthetic route to functionalized bi- and tricyclic lactams (up to > 20:1 dr and 99 % ee) in one pot from simple starting materials (allylic alcohols, enals, diamines and amino alcohols) using cascade transformations promoted by chiral amine/Brønsted or metal/chiral amine/Brønsted relay catalysis is disclosed. Here molecular oxygen is employed as the terminal oxidant for the latter relay catalysis approach. 

  • 40.
    Jiang, Yan
    et al.
    Stockholm University, Stockholm.
    Deiana, Luca
    Stockholm University, Stockholm.
    Zhang, Keihang
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Lin, Shuangzheng
    Stockholm University, Stockholm.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap.
    Total Asymmetric Synthesis of Quinine, Quinidine, and Analogues via Catalytic Enantioselective Cascade Transformations2019Inngår i: European Journal of Organic Chemistry, ISSN 1434-193X, E-ISSN 1099-0690, nr 35, s. 6016-6023Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A catalytic asymmetric strategy for the total synthesis of quinuclidine natural products, which includes the completed enantioselective synthesis of the classical targets quinine and quinidine is disclosed. It is based on catalytic asymmetric cascade transformations, which paves the road for the synthesis of both enantiomers of the crucial C4 stereocenter with high enantioselectivity (up to 99 % ee) in one pot. Next, developing a route to all possible stereoisomers of a common early-stage intermediate sets the stage for the total synthesis of different enantiomers or epimers of quinine, quinidine and analogues with high selectivity. 

  • 41.
    Kohls, Hannes
    et al.
    Ernst Moritz Arndt Univ Greifswald, Inst Biochem, D-17487 Greifswald, Germany.
    Anderson, Mattias
    AlbaNova Univ Ctr, Sch Biotechnol, Div Ind Biotechnol, KTH Royal Inst Technol, SE-10691 Stockholm, Sweden.
    Dickerhoff, Jonathan
    Ernst Moritz Arndt Univ Greifswald, Inst Biochem, D-17487 Greifswald, Germany.
    Weisz, Klaus
    Ernst Moritz Arndt Univ Greifswald, Inst Biochem, D-17487 Greifswald, Germany.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Berglund, Per
    AlbaNova Univ Ctr, Sch Biotechnol, Div Ind Biotechnol, KTH Royal Inst Technol, SE-10691 Stockholm, Sweden.
    Brundiek, Henrike
    Enzymicals AG, D-17489 Greifswald, Germany.
    Bornscheuer, Uwe T.
    Ernst Moritz Arndt Univ Greifswald, Inst Biochem, D-17487 Greifswald, Germany.
    Hoehne, Matthias
    Ernst Moritz Arndt Univ Greifswald, Inst Biochem, D-17487 Greifswald, Germany.
    Selective Access to All Four Diastereomers of a 1,3-Amino Alcohol by Combination of a Keto Reductase- and an Amine Transaminase-Catalysed Reaction2015Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 357, nr 8, s. 1808-1814Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The biocatalytic synthesis of chiral amines has become a valuable addition to the chemists' tool-box. However, the efficient asymmetric synthesis of functionalised amines bearing more than one stereocentre, such as 1,3-amino alcohols, remains challenging. By employing a keto reductase (KRED) and two enantiocomplementary amine transaminases (ATA), we developed a biocatalytic route towards all four diastereomers of 4-amino-1-phenylpentane-2-ol as a representative molecule bearing the 1,3-amino alcohol functionality. Starting from a racemic hydroxy ketone, a kinetic resolution using an (S)-selective KRED provided optically active hydroxy ketone (86% ee) and the corresponding diketone. Further transamination of the hydroxy ketone was performed by either an (R)- or an (S)-selective ATA, yielding the (2R,4R)- and (2R,4S)-1,3-amino alcohol diastereomers. The remaining two diastereomers were accessible in two subsequent asymmetric steps: the diketone was reduced regio- and enantioselectively by the same KRED, which yielded the (S)-configured hydroxy ketone. Eventually, the subsequent transamination of the crude product with (R)- and (S)-selective ATAs yielded the remaining (2S,4R)and (2S,4S)-diastereomers, respectively.

  • 42. Lin, S
    et al.
    Zhao, G-L
    Deiana, L
    Sun, J
    Zhang, Q
    Leijonmarck, H
    Còrdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Dynamic kinetic asymmetric domino oxa-michael/carbocyclization by combination of transition-metal and amine catalysis: Catalytic enantioselective synthesis of dihydrofurans2010Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 16, nr 47, s. 13930-13934Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Into the pot: A one-pot highly chemo- and enantioselective catalytic domino oxa-Michael/carbocyclization between α,β-unsaturated aldehydes and propargylic alcohols is presented. This dynamic kinetic transformation requires a combination of transition-metal and amine catalysis to afford functionalized dihydrofurans in good to high yields and up to 99.5:0.5 e.r.

  • 43.
    Lin, Shuangzheng
    et al.
    Stockholm Univ, Dept Organ Chem, Arrhenius Lab, S-10691 Stockholm, Sweden .
    Deiana, Luca
    Stockholm Univ, Dept Organ Chem, Arrhenius Lab, S-10691 Stockholm, Sweden .
    Zhao, Gui-Ling
    Stockholm Univ, Dept Organ Chem, Arrhenius Lab, S-10691 Stockholm, Sweden .
    Sun, Junliang
    Stockholm Univ, Arrhenius Lab, Berzelii Ctr EXSELENT Porous Mat, S-10691 Stockholm, Sweden .
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Dynamic One-Pot Three-Component Catalytic Asymmetric Transformation by Combination of Hydrogen-Bond-Donating and Amine Catalysts2011Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 50, nr 33, s. 7624-7630Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In control: The first dynamic one-pot three-component asymmetric transformation between aldehydes, protected α-cyanoglycine esters, and enals catalyzed by a combination of a simple hydrogen-bond-donating catalyst and a chiral amine catalyst is disclosed. Polysubstituted proline derivatives, which have a quaternary α stereocenter, were synthesized with high endo-, diastereo-, and enantioselectivities (93-99 ee). Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  • 44.
    Ma, Guangning
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Deiana, L.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, Sweden .
    Palo-Nieto, C.
    Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, Sweden .
    Liu, L.
    Berzelii Center EXSELENT, Stockholm University, Sweden .
    Sun, J.
    Berzelii Center EXSELENT, Stockholm University, Sweden .
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    A palladium/chiral amine co-catalyzed enantioselective dynamic cascade reaction: Synthesis of polysubstituted carbocycles with a quaternary carbon stereocenter2013Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, nr 23, s. 6050-6054Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Polysubstituted 5- and 6-membered carbocycles were synthesized by the title reaction. The one-pot dynamic relay process generates four new stereocenters, including a quaternary carbon center, in a highly enantioselective fashion (99.5:0.5→99:0.5 e.r.) by using a simple combination of palladium and chiral amine co-catalysts. 

  • 45.
    Ma, Guangning
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Bartoszewicz, Agnieszka
    Stockholm Univ, Arrhenius Lab, Dept Organ Chem, SE-10691 Stockholm, Sweden .
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Highly Enantioselective Co-Catalytic Direct Aldol reactions by Combination of Hydrogen-Bond Donating and Acyclic Amino Acid Catalysts2011Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 353, nr 17, s. 3114-3122Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Highly enantioselective co-catalytic direct aldol reactions by a combination of simple hydrophobic acyclic amino acid and hydrogen-bond donating catalysts are presented. The corresponding aldol products are formed in high yields with high regio-, diastereo- (anti or syn) and enantioselectivity (up to 99.5:0.5 er). The catalyst loadings can be decreased to as little as 2 mol%.

  • 46.
    Ma, Guangning
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Lin, Shuangzheng
    Stockholm Univ, Dept Organ Chem, Arrhenius Lab, S-10691 Stockholm, Sweden .
    Ibrahem, Ismail
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Kubik, Grzegorz
    Stockholm Univ, Dept Organ Chem, Arrhenius Lab, S-10691 Stockholm, Sweden .
    Liu, Leifeng
    Stockholm Univ, Dept Mat & Environm Chem, Arrhenius Lab, S-10691 Stockholm, Sweden.
    Sun, Junliang
    Stockholm Univ, Dept Mat & Environm Chem, Arrhenius Lab, S-10691 Stockholm, Sweden.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för tillämpad naturvetenskap och design.
    Achiral Co-Catalyst Induced Switches in Catalytic Asymmetric Reactions on Racemic Mixtures (RRM): From Stereodivergent RRM to Stereoconvergent Deracemization by Combination of Hydrogen Bond Donating and Chiral Amine Catalysts2012Inngår i: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 354, nr 14-15, s. 2865-2872Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A stereochemical divergent approach for the highly enantioselective synthesis of distinct bicyclic products with multiple stereocenters from a racemate using a single chiral catalyst is disclosed. It is based on switches of the overall reaction pathways in the chiral amine-catalyzed cascade reactions between racemic ?-nitro ketones and a,beta-unsaturated aldehydes using different achiral co-catalysts. The utility of the method is exemplified by the highly diasteroselective switch and stereoconvergent deracemization process by combination of chiral amine and achiral hydrogen-bond-donating catalysts.

  • 47.
    Mridha, Moniruzzaman
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Uppsala University.
    Ma, Guangning
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Palo-Nieto, Carlos
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm University.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm University.
    Development of an Amino Acid/Hydroxy Oxime Dual Catalyst System for Highly Stereoselective Direct Asymmetric Aldol Reactions in the Presence of Water2017Inngår i: Synthesis (Stuttgart), ISSN 0039-7881, E-ISSN 1437-210X, Vol. 49, nr 2, s. 383-390, artikkel-id ss-2015-z0592-opArtikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An eco-friendly dual catalyst system for stereoselective aldol reactions in the presence of water is described. It is based on the cooperative action of acyclic amino acids and H-bond donating hydroxy oxime catalysts. The synthetic utility of this dual catalyst system was further demonstrated by applying it as the key step in the expeditious and highly stereoselective total synthesis of D-lyxo-phytosphingosine (29% overall yield). Here the amino acid/hydroxy oxime system significantly accelerated the direct aldol reactions in the presence of water as compared to organic solvents. The stereo-and chemoselectivity were also significantly increased.

  • 48. Nozière, Barbara
    et al.
    Dziedzic, Pawel
    Córdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för naturvetenskap, teknik och matematik.
    Common Inorganic Ions Catalyze Chemical Reactions of Organic Compounds in Atmospheric Aerosols2010Inngår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 12, s. 3864-Artikkel i tidsskrift (Fagfellevurdert)
  • 49.
    Osong, Sinke H.
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Norgren, Sven
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Pettersson, Gunilla
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Engstrand, Per
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för kemiteknik.
    Còrdova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Alimohammadzadeh, Rana
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Processing of nanocellulose and applications relating to CTMP-based paperboard and foams2016Inngår i: International Mechanical Pulping Conference 2016, IMPC 2016, TAPPI Press, 2016, s. 87-93Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Although remarkable success has been made in the production of nanocellulose through several processing methods, it still remain a challenge to reduce the overall energy consumption, to use green chemistry and sustainable approach in order to make it feasible for industrial production of this novel nanomaterial. Herein, we have developed a new eco-friendly and sustainable approach to produce nanocellulose using organic acid combined with high-shear homogenisation, made hydrophobisation of nanocellulose and cross-linked the modified nanocellulosic material. Also, TEMPO-mediated oxidised nanocellulose was produced in order to compare the processing route with that of mild organic acid hydrolysis. Freeze-dried 3D structure of TEMPO-derived nanocellulose foam materials made fi-om bleached sulphite pulp and CTMP, respectively. Further, there is growing interest in using nanocellulose or microfibrillated cellulose (MFC) as an alternative paper sfrength additive in papermaking, and in using chemi-thermomechanical pulp (CTMP) with high freeness in producing CTMP-based paperboard with high bulk properties. To achieve greater strength improvement results, particularly for packaging paperboards, different proportions of cationic starch (CS) or MFC can be used to significantly improve the z-strength, with only a slight increase in sheet density. Research in this area is exploring CS or MFC as potential strength additives in CTMP-based paperboard, which is interesting from an industrial perspective. The mean grammage of the CTMP handsheets produced was approximately 150 g m~, and it was found that blending CTMP with CS or MFC yielded handsheets with significantly improved z-strength, tensile index, burst index and other strength properties at similar sheet densities.

  • 50.
    Palo-Nieto, Carlos
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Afewerki, Samson
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap.
    Anderson, Mattias
    AlbaNova Univ Ctr, KTH Royal Inst Technol, Sch Biotechnol, Div Ind Biotechnol, SE-10691 Stockholm, Sweden.
    Tai, Cheuk-Wai
    Stockholm Univ, Dept Mat & Environm Chem, Berzelii Ctr EXSELENT Porous Mat, S-10691 Stockholm, Sweden.
    Berglund, Per
    AlbaNova Univ Ctr, KTH Royal Inst Technol, Sch Biotechnol, Div Ind Biotechnol, SE-10691 Stockholm, Sweden.
    Cordova, Armando
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för naturvetenskap. Stockholm Univ, Dept Mat & Environm Chem, Berzelii Ctr EXSELENT Porous Mat, S-10691 Stockholm, Sweden.
    Integrated Heterogeneous Metal/Enzymatic Multiple Relay Catalysis for Eco-Friendly and Asymmetric Synthesis2016Inngår i: ACS Catalysis, ISSN 2155-5435, E-ISSN 2155-5435, Vol. 6, nr 6, s. 3932-3940Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Organic synthesis is in general performed using stepwise transformations where isolation and purification of key intermediates is often required prior to further reactions. Herein we disclose the concept of integrated heterogeneous metal/enzymatic multiple relay catalysis for eco-friendly and asymmetric synthesis of valuable molecules (e.g., amines and amides) in one-pot using a combination of heterogeneous metal and enzyme catalysts. Here reagents, catalysts, and different conditions can be introduced throughout the one-pot procedure involving multistep catalytic tandem operations. Several novel cocatalytic relay sequences (reductive amination/amidation, aerobic oxidation/reductive amination/amidation, reductive amination/kinetic resolution and reductive amination/ dynamic kinetic resolution) were developed. They were next applied to the direct synthesis of various biologically and optically active amines or amides in one-pot from simple aldehydes, ketones, or alcohols, respectively.

12 1 - 50 of 63
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