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  • 1. Afewerki, Samson
    et al.
    Breistein, Palle
    Deiana, Luca
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Dziedzic, Pawel
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Catalytic enantioselective β -alkylation of α,β-unsaturated aldehydes by combination of transition-metal- and aminocatalysis: Total synthesis of bisabolane sesquiterpenes2011In: Chemistry: a European Journal, ISSN 0947-6539, Vol. 17, no 32, p. 8784-8788Article in journal (Refereed)
  • 2. Afewerki, Samson
    et al.
    Ibrahem, Ismail
    Rydfjord, Jonas
    Breistein, Palle
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Direct Regiospecific and Highly Enantioselective Intermolecular α-Allylic Alkylation of Aldehydes by a Combination of Transition-Metal and Chiral Amine Catalysts2012In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 18, no 10, p. 2972-2977Article in journal (Refereed)
    Abstract [en]

    The first direct intermolecular regiospecific and highly enantioselective a-allylic alkylation of linear aldehydes by a combination of achiral bench-stable Pd0 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 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.

  • 3. Breistein, Palle
    et al.
    Johansson, Jonas
    Ibrahem, Ismail
    Lin, Shuangzheng
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Deiana, Luca
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sun, Junliang
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Inorganic and Structural Chemistry.
    Cordova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry. Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Inorganic and Structural Chemistry.
    One-Step Catalytic Enantioselective a-Quaternary 5-Hydroxyproline Synthesis: An Asymmetric Entry to Highly Functionalized a-Quaternary Proline Derivatives2012In: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 354, no 6, p. 1156-1162Article in journal (Refereed)
    Abstract [en]

    The highly enantioselective cascade reaction between N-protected a-cyanoglycine esters and a,beta-unsaturated aldehydes is disclosed. The reaction represents a one-step entry to polysubstituted 5-hydroxyproline derivatives having a quaternary a-stereocenter generally in high yields with up to >95:5 dr and 99:1 er. It is also a direct catalytic two-step entry to functionalized a-quaternary proline derivatives.

  • 4.
    Córdova, Armando
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Engqvist, Magnus
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Casas, Jésus
    Sundén, Henrik
    Plausible origins of homochirality in the amino acid catalyzed neogenesis of carbohydrates2005In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 2005, p. 2047-2049Article in journal (Refereed)
    Abstract [en]

    The intrinsic ability of amino acids to catalyze the asymmetric formation of carbohydrates, which enzymes have mediated for millions of years, with significant amplification of enantiomeric excess suggests a plausible ancient catalytic process for the evolution of homochirality.

  • 5.
    Córdova, Armando
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Casas, Jesús
    Sundén, Henrik
    Engqvist, Magnus
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Reyes, Efraim
    Amino Acid-Catalyzed Neogenesis of Carbohydrates: A Plausible Ancient Transformation2005In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 11, no 16, p. 4772-4784Article in journal (Refereed)
    Abstract [en]

    Hexose sugars play a fundamental role in vital biochemical processes and their biosynthesis is achieved through enzyme-catalyzed pathways. Herein we disclose the ability of amino acids to catalyze the asymmetric neogenesis of carbohydrates by sequential cross-aldol reactions. The amino acids mediate the asymmetric de novo synthesis of natural L- and D-hexoses and their analogues with excellent stereoselectivity in organic solvents. In some cases, the four new stereocenters are assembled with almost absolute stereocontrol. The unique feature of these results is that, when an amino acid is employed as the catalyst, a single reaction sequence can convert a protected glycol aldehyde into a hexose in one step. For example, proline and its derivatives catalyze the asymmetric neogenesis of allose with >99 % ee in one chemical manipulation. Furthermore, all amino acids tested catalyzed the asymmetric formation of natural sugars under prebiotic conditions, with alanine being the smallest catalyst. The inherent simplicity of this catalytic process suggests that a catalytic prebiotic “gluconeogenesis” may occur, in which amino acids transfer their stereochemical information to sugars. In addition, the amino acid catalyzed stereoselective sequential cross-aldol reactions were performed as a two-step procedure with different aldehydes as acceptors and nucleophiles. The employment of two different amino acids as catalysts for the iterative direct aldol reactions enabled the asymmetric synthesis of deoxysugars with >99 % ee. In addition, the direct amino acid catalyzed C2+C2+C2 methodology is a new entry for the short, highly enantioselective de novo synthesis of carbohydrate derivatives, isotope-labeled sugars, and polyketide natural products. The one-pot asymmetric de novo syntheses of deoxy and polyketide carbohydrates involved a novel dynamic kinetic asymmetric transformation (DYKAT) mediated by an amino acid.

  • 6.
    Deiana, Luca
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramon
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sun, Junliang
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Catalytic asymmetric aziridination of α, β- unsaturated aldehydes2011In: Abstracts of Papers, 242nd ACS National Meeting & Exposition, Denver, CO, United States, August 28-September 1, 2011, American Chemical Society , 2011Conference paper (Other academic)
    Abstract [en]

    The development, scope and application of the highly enantioselective organocatalytic aziridination of a, b- unsaturated aldehydes is presented. The aminocatalytic aziridination of a, b- unsaturated aldehydes enables the asymmetric formation of b-formylaziridines with up to >19:1 dr and 99% ee. The aminocatalytic aziridination of a-monosobstituted enals gives access to terminal a-substituted-a-formyl aziridines in high yields and up to 99% ee. In the case of the organocatalytic aziridination of disubstituted a, b-unsaturated aldehydes, the transformations gives nearly enantiomeric pure b-formyl-functionalized aziridine products. A higly enantioselective one-pot cascade sequence based on combination of asymmetric amine and N-heterocyclic carbene catalysis is also disclosed. This transformation gives the corresponding N-Boc and N-Cbz protected b-amino acid esters with ee´s ranging from 92-99%.

  • 7.
    Deiana, Luca
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Dziedzic, Pawel
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sun, Junliang
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry, Structural Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Catalytic asymmetric aziridination of α,β-unsaturated aldehydes2011In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 17, no 28, p. 7904-7917Article in journal (Refereed)
    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 upto 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-heterocycliccarbene 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.

  • 8.
    Dziedzic, Pawel
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Direct catalytic asymmetric three-component Mannich reactions with dihydroxyacetone: enantioselective synthesis of amino sugar derivatives2008In: Tetrahedron Letters, ISSN 0040-4039, E-ISSN 1359-8562, Vol. 49, no 5, p. 803-807Article in journal (Refereed)
    Abstract [en]

    Highly enantioselective, amino acid-catalyzed, one-pot three-component asymmetric Mannich reactions between dihydroxyacetone, p-anisidine, and aldehydes are presented. The reactions proceeded with high chemo- and stereoselectivity and furnished the corresponding α,α′-dihydroxy-β-aminoketones in high yields with 82–95% ee.

  • 9.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Development of organocatalytic asymmetric transformations2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The ability of amino acids and amino acid derivatives to mediate various organocatalytic asymmetric transformations has been investigated and applied in the development of various reactions. This work describes the development of a direct catalytic asymmetric α-aminomethylation of ketones and aldehydes, a catalytic asymmetric aziridination, hydrophosphination and amination of α,β-unsaturated aldehydes.

  • 10. Ibrahem, Ismail
    et al.
    Breistein, Palle
    Cordova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    One-Pot Three-Component Highly Selective Synthesis of Homoallylboronates by Using Metal-Free Catalysis2012In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 18, no 17, p. 5175-5179Article in journal (Refereed)
  • 11. Ibrahem, Ismail
    et al.
    Breistein, Palle
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    One-Pot Three-Component Catalytic Enantioselective Synthesis of Homoallylboronates2011In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 50, no 50, p. 12036-12041Article in journal (Refereed)
  • 12.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Casas, Jesus
    Cordova, Armando
    Direct Catalytic Enantioselective a-aminomethylation of ketones2004In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 43, p. 6528-Article in journal (Refereed)
  • 13.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Dziedzic, Pawel
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Organocatalytic asymmetric alpha-aminomethylation of cyclohexanones2006In: Synthesis, ISSN 0039-7881, no 23, p. 4060-4064Article in journal (Refereed)
  • 14.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Hammar, Peter
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Eriksson, Lars
    Department of Physical, Inorganic and Structural Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Organocatalytic asymmetric hydrophosphination of alpha,beta-unsaturated aldehydes: Development, mechanism and DFT calculations2008In: Advanced Synthesis & Catalysis, ISSN 1615-4150, Vol. 350, no 11-12, p. 1875-1884Article in journal (Refereed)
  • 15. Ibrahem, Ismail
    et al.
    Iqbal, Muhammad Naeem
    Stockholm University, Faculty of Science, Department of Organic Chemistry. Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Verho, Oscar
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Eivazihollagh, Alireza
    Olsén, Peter
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Edlund, Håkan
    Tai, Cheuk-Wai
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Norgren, Magnus
    Johnston, Eric V.
    Copper Nanoparticles on Controlled Pore Glass and TEMPO for the Aerobic Oxidation of Alcohols2018In: ChemNanoMat, ISSN 2199-692X, Vol. 4, no 1, p. 71-75Article in journal (Refereed)
    Abstract [en]

    Herein, we report on the facile synthesis of a heterogeneous copper nanocatalyst and its combination with 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) for the aerobic oxidation of alcohols to their corresponding carbonyl compounds. This low cost copper nanocatalyst was found to exhibit excellent recyclability, making it a highly attractive catalytic system from an economical and environmental point of view. Extensive characterization of the catalyst by a number of techniques revealed that it was comprised of well-dispersed Cu(I/II) nanoparticles with an average size of around 6nm.

  • 16. Ibrahem, Ismail
    et al.
    Ma, Guangning
    Afewerki, Samson
    Cordova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Palladium/chiral amine co catalyzed enantioselective beta arylation of alpha,beta unsaturated aldehydes2013In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, no 3, p. 878-882Article in journal (Refereed)
  • 17.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramon
    Vesely, Jan
    Hammar, Peter
    Eriksson, Lars
    Himo, Fahmi
    Cordova, Armando
    Enantioselective Organocatalytic Hydrophosphination of α,β- Unsaturated Aldehydes2007In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 46, p. 4507-Article in journal (Refereed)
  • 18.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramon
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Cordova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Catalytic enantioselective 5-hydroxyisoxazolidine synthesis: An asymmetric entry to beta-amino acids2008In: Synthesis (Stuttgart), ISSN 0039-7881, E-ISSN 1437-210X, no 7, p. 1153-1157Article in journal (Refereed)
    Abstract [en]

    The highly chemo- and enantioselective organocatalytic tandem reaction between N-carbamate-protected hydroxylamines and a,p-unsaturated aldehydes is presented. The reaction represents a unique entry for the asymmetric synthesis of 5-hydroxyisoxazolidines, oxazolidin-5-ones or gamma-hydroxyamino alcohols in high yields and 90-99% ee. A procedure for the conversion of the oxazolidin-5-ones into the corresponding beta-amino acids is also described.

  • 19.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramon
    Vesely, Jan
    Zhao, Guiling
    Cordova, Armando
    Organocatalytic Asymmetric 5-Hydroxyisoxazolidine Synthesis: A Highly Enantioselective Route to β-Amino Acids2007In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, p. 849-852Article in journal (Refereed)
  • 20.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Enantioselective organocatalytic hydrophosphination of alpha,beta-unsaturated aldehydes2007In: Abstracts of Papers, 234th ACS National Meeting, Boston, MA, United States, August 19-23, 2007, 2007Conference paper (Other academic)
  • 21.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Organocatalytic asymmetric multi-component [C+NC+CC] synthesis of highly functionalized pyrrolidine derivatives2007In: Tetrahedron Letters, ISSN 0040-4039, Vol. 48, no 36, p. 6252-6257Article in journal (Refereed)
  • 22.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Hammar, Peter
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Himo, Fahmi
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Enantioselective organocatalytic hydrophosphination of alpha,beta-unsaturated aldehydes2007In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 46, p. 4507-4510Article in journal (Refereed)
  • 23.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Catalytic enantioselective 5-hydroxyisoxazolidine synthesis: an asymmetric entry to beta-amino acids2007In: Synthesis, ISSN 0039-7881, no 7, p. 1153-1157Article in journal (Refereed)
  • 24.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Organocatalytic asymmetric 5-hydroxyisoxazolidine synthesis: a highly enantioselective route to beta-amino acids2007In: Chemical Communications, p. 849-851Article in journal (Refereed)
  • 25.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Organocatalytic asymmetric 5-hydroxyisoxazolidine synthesis: a highly enantioselective route to beta-amino acids2007In: Abstracts of Papers, 234th ACS National Meeting, Boston, MA, United States, August 19-23, 2007, 2007Conference paper (Other academic)
  • 26. Ibrahem, Ismail
    et al.
    Santoro, Stefano
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Himo, Fahmi
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Enantioselective conjugate silyl additions to α,β-unsaturated aldehydes catalyzed by combination of transition metal and chiral amine catalysts2011In: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 353, no 2+3, p. 245-252Article in journal (Refereed)
    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 α,β-unsaturated aldehydes. These reactions proceed with excellent 1,4-selectivity to afford the corresponding β-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 canalso generate a quaternary stereocenter with goodenantioselectivity. Density functional calculations are performed to elucidate the reaction mechanism and the origin of enantioselectivity.

  • 27.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sundén, Henrik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Dziedzic, Pawel
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Asymmetric amplification in the amino acid-catalyzed synthesis of amino acid derivatives2007In: Advanced Synthesis & Catalysis, ISSN 1615-4150, Vol. 349, no 11-12, p. 1868-1872Article in journal (Refereed)
  • 28.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sundén, Henrik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    One-pot pyrrolidine-catalyzed synthesis of benzopyrans, benzothiopyranes, and dihydroquinolidines2007In: Chimia, ISSN 0009-4293, Vol. 61, no 5, p. 219-223Article in journal (Refereed)
  • 29.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Guiling
    Cordova, Armando
    Direct Catalytic Enantioselective α-Aminomethylation of Aldehydes2007In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 13, p. 683-Article in journal (Refereed)
  • 30.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Direct catalytic enantioselective alpha-aminomethylation of aldehydes2007In: Chemistry: a European journal, Vol. 13, p. 683-688Article in journal (Refereed)
  • 31.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sundén, Henrik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Dziedzic, Pawel
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    One-pot organocatalytic domino Michael/alpha-alkylation reactions: direct catalytic enantioselective cyclopropanation and cyclopentanation reactions2008In: Chemistry: a European journal, ISSN 0947-6539, Vol. 14, no 26, p. 7867-7879Article in journal (Refereed)
  • 32.
    Ibrahem, Ismail
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zou, Weibiao
    Casas, Jesus
    Sunden, Henrik
    Cordova, Armando
    Direct Organocatalytic Enantioselective α-Aminomethylation of Ketones2006In: Tetrahedron, Vol. 62, p. 357-Article in journal (Refereed)
  • 33. Ma, Guangning
    et al.
    Afewerki, Samson
    Deiana, Luca
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Palo-Nieto, Carlos
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Liu, Leifeng
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Inorganic and Structural Chemistry.
    Sun, Junliang
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK), Inorganic and Structural Chemistry.
    Ibrahem, Ismail
    Cordova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    A Palladium/Chiral Amine Co-catalyzed Enantioselective Dynamic Cascade Reaction: Synthesis of Polysubstituted Carbocycles with a Quaternary Carbon Stereocenter2013In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 52, no 23, p. 6050-6054Article in journal (Refereed)
  • 34.
    Ma, Guangning
    et al.
    Mid Sweden University, Department of Natural Sciences, Engineering and Mathematics.
    Bartoszewicz, Agnieszka
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Mid Sweden University, Department of Natural Sciences, Engineering and Mathematics.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Highly enantioselective co-catalytic direct aldol reactions by combination of hydrogen-bond donating and acyclic amino acid catalysts2011In: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 353, no 17, p. 3114-3122Article in journal (Refereed)
    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%.

  • 35. Ma, Guangning
    et al.
    Lin, Shuangzheng
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Kubik, Grzegorz
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Liu, Leifeng
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Sun, Junliang
    Stockholm University, Faculty of Science, Department of Materials and Environmental Chemistry (MMK).
    Cordova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    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 Catalysts2012In: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 354, no 14-15, p. 2865-2872Article in journal (Refereed)
    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.

  • 36.
    Rios, Ramón
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Organocatalytic multicomponent pyrrolidine synthesis2008In: Abstracts of Papers, 235th ACS National Meeting, New Orleans, LA, United States, April 6-10, 2008, 2008Conference paper (Other academic)
  • 37.
    Rios, Ramón
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sundén, Henrik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Organocatalytic asymmetric 5-hydroxypyrrolidine synthesis: a highly enantioselective route to 3-substituted proline derivatives2007In: Tetrahedron Letters, ISSN 0040-4039, Vol. 48, p. 8695-8699Article in journal (Refereed)
  • 38.
    Rios, Ramón
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sundén, Henrik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Organocatalytic asymmetric 5-hydroxypyrrolidine synthesis: a highly enantioselective route to 3-substituted proline derivatives2008In: Abstracts of Papers, 235th ACS National Meeting, New Orleans, LA, United States, April 6-10, 2008, 2008Conference paper (Other academic)
  • 39.
    Rios, Ramón
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    A simple one-pot, three-component, catalytic, highly enantioselective isoxazolidine synthesis2007In: Tetrahedron Letters, ISSN 0040-4039, Vol. 48, no 32, p. 5701-5705Article in journal (Refereed)
  • 40.
    Rios, Ramón
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Three component organocatalytic 1,3-dipolar cycloaddition2007In: Abstracts of Papers, 234th ACS National Meeting, Boston, MA, United States, August 19-23, 2007, 2007Conference paper (Other academic)
  • 41.
    Rios, Ramón
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sundén, Henrik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    A simple and concise catalytic asymmetric entry to tetrahydroxanthenones2007In: Tetrahedron Letters, Vol. 48, p. 2181-2184Article in journal (Refereed)
  • 42.
    Rios, Ramón
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sundén, Henrik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    A one-pot organocatalytic asymmetric entry to tetrahydrothioxanthenones2006In: Tetrahedron Letters, Vol. 47, no 49, p. 8679-8682Article in journal (Refereed)
  • 43.
    Rios, Ramón
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    One-pot catalytic asymmetric cascade synthesis of cycloheptane derivatives2008In: Abstracts of Papers, 235th ACS National Meeting, New Orleans, LA, United States, April 6-10, 2008, 2008Conference paper (Other academic)
  • 44.
    Rios, Ramón
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Organocatalytic multicomponent reaction: total control up to 5 stereocenters2007In: Abstracts of Papers, 234th ACS National Meeting, Boston, MA, United States, August 19-23, 2007, 2007Conference paper (Other academic)
  • 45.
    Rios, Ramón
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Vesely, Jan
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sundén, Henrik
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    One-pot organocatalytic domino Michael/alpha-alkylation reactions: highly enantioselective synthesis of functionalized cyclopentanones and cyclopentanols2007In: Tetrahedron Letters, Vol. 48, p. 5835-5839Article in journal (Refereed)
  • 46.
    Sundén, Henrik
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry. -.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry. -.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry. -.
    Eriksson, Lars
    Department of Physical, Inorganic and Structural Chemistry. -.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry. -.
    Catalytic enantioselective domino oxa-Michael/aldol condensations: asymmetric synthesis of benzopyran derivatives: -2007In: Chemistry: a European journal: -, ISSN -, Vol. 13, no -, p. 574-581Article in journal (Refereed)
  • 47.
    Sundén, Henrik
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Eriksson, Lars
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    A highly enantioselective catalytic domino aza-Michael/aldol reaction: one-pot organocatalytic asymmetric synthesis of 1,2-dihydroquinolidines2007In: Advanced Synthesis and Catalysis, ISSN 1615-4150, E-ISSN 1615-4169, Vol. 349, p. 827-832Article in journal (Refereed)
  • 48.
    Ullah, Farman
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Deiana, Luca
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhu, Mingzhao
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Dziedzic, Pawel
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Hammar, Peter
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Sun, Junliang
    Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry, Department of Structural Chemistry. Stockholm University, Faculty of Science, Department of Physical, Inorganic and Structural Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Enantioselective organocatalytic conjugate addition of fluorocarbon nucleophiles to α,β-unsaturated aldehydes2009In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 15, no 39, p. 10013-10017Article in journal (Refereed)
    Abstract [en]

    A highly chemo- and enantioselective organocatalytic addition of fluorocarbon nucleophiles, such as 1-fluoro-bis(phenylsulfonyl)methane, toα,β-unsaturated aldehydes is presented (see scheme). The reactions are catalyzed by simple chiral amines and give access to optically active fluorine derivatives in good yields and up to 95 % ee. Notably, the methodology can be applied to the formation of a chiral quaternary carbon center bearing a fluorine atom with high enantioselectivity.

  • 49.
    Vesely, Jan
    et al.
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Rios, Ramón
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Gui-Ling
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Xu, Yongmei
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Córdova, Armando
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Enantioselective organocatalytic conjugate addition of amines to alpha-beta-unsaturated aldehydes: one-pot asymmetric synthesis of beta-amino acids and 1,3-diamines2007In: Tetrahedron Letters, Vol. 48, p. 2193-2198Article in journal (Refereed)
  • 50. Vesely, Jan
    et al.
    Ibrahem, Ismail
    Stockholm University, Faculty of Science, Department of Organic Chemistry.
    Zhao, Guiling
    Rios, Ramon
    Cordova, Armando
    Organocatalytic Enantioselective Aziridination of α,β-Unsaturated Aldehydes2007In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 46, p. 778-Article in journal (Refereed)
12 1 - 50 of 59
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