Home  About us  Contact
 

Organocatalyst

Distribution by Scientific Domains
Chemistry100%
Distribution within Chemistry
Organic Chemistry83%
General & Introductory Chemistry12%
4 Other Subdomains5%

Kinds of Organocatalyst

  • bifunctional organocatalyst
    		•
  • efficient organocatalyst
    		•
  • novel organocatalyst
    		•

    Selected Abstracts

    Highly Enantioselective Conjugate Addition of Ketones to Alkylidene Malonates Catalyzed by a Pyrrolidinyl,Camphor-Derived Organocatalyst

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 11 2010
    Dhananjay R. Magar
    Abstract Pyrrolidinyl,camphor derivatives have been proven to be efficient organocatalysts for enantioselective conjugate addition of ketones to alkylidene malonates, affording high chemical yields (up to 95,%) of the corresponding products with high to excellent levels of diastereoselectivity (up to >99:1,dr) and enantioselectivity (up to 96,%,ee) under solvent-free reaction conditions at ambient temperature. [source]

    2-[(Imidazolylthio)methyl]pyrrolidine as a Trifunctional Organocatalyst for the Highly Asymmetric Michael Addition of Ketones to Nitroolefins

    EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 6 2008
    Dan-Qian Xu
    Abstract The direct asymmetric Michael addition of ketones to nitroolefins catalyzed by 2-[(imidazol-2-ylthio)methyl]pyrrolidine, constructed from natural L -proline and imidazolylthio platforms, with salicylic acid as a co-catalyst has been developed to give the products in high yields (up to 95,%) and with excellent enantioselectivities (up to 99,% ee). The highly efficient catalytic performance may be attributed to the dual activation of the Michael substrates by the trifunctional organocatalysts and the co-catalyst salicylic acid, leading to the formation of a stable transition state complex through the synergic effect of hydrogen-bonding and electrostatic interactions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source]

    Imidazolium Ion-Tagged Proline Organocatalyst for ,-Aminoxylation of Aldehydes and Ketones in Ionic Liquids

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 1 2010
    Xiong Ding
    Abstract A novel imidazolium ion-tagged L -proline catalyst has been developed. The asymmetric ,-aminoxylation of aldehydes and ketones with excellent enantioselectivities, up to 99% ee, and high yields in ionic liquids has been achieved. The system can be easily recycled and reused for at least six times without significant loss of yields and enantioselectivity. [source]

    A Highly Selective, Polymer-Supported Organocatalyst for Michael Additions with Enzyme-Like Behavior

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 18 2009
    Esther Alza
    Abstract A polymer-supported ,,,-diarylprolinol silyl ether displays catalytic activity and enantioselectivity comparable to the best homogeneous catalysts in the Michael addition of aldehydes to nitroolefins. Above all, the combination of polymer backbone, triazole linker, and catalytic unit confers to it an unprecedented substrate selectivity in favor of linear, short-chain aldehydes. [source]

    4-Aminothiourea Prolinol tert -Butyldiphenylsilyl Ether: A Chiral Secondary Amine-Thiourea as Organocatalyst for Enantioselective anti -Mannich Reactions

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009
    Hui Zhang
    Abstract anti -Selective Mannich reactions of N - p -methoxyphenyl (PMP)-protected ,-iminoglyoxylate with unmodified aldehydes or ketones were effectively catalyzed by 4-aminothiourea prolinol tert -butyldiphenylsilyl ether. The reactions led to chiral ,-amino carbonyl compounds in high yields (up to 94%), excellent diastereo- and enantioselectivities (up to 98% de and >99% ee). The study demonstrated for the first time that direct Mannich-type reactions of unmodified aldehydes or ketones to ,-iminoglyoxylate can be promoted by secondary amine-thiourea chiral organocatalyst. [source]

    Imidazolium-2-Carboxylate as an Efficient, Expeditious and Eco-Friendly Organocatalyst for Glycerol Carbonate Synthesis

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2009
    Prashant
    Abstract An improved and greener approach towards the synthesis of glycerol carbonate, via transesterification, using 1- n -butyl-3-methylimidazolium-2-carboxylate as catalyst is described. The catalyst loading as low as 1% was sufficient to yield quantitative conversions. A plausible mechanism is proposed for the catalytic cycle leading to product formation. [source]

    Pyrrolidine-Camphor Derivative as an Organocatalyst for Asymmetic Michael Additions of ,,,-Disubstituted Aldehydes to ,-Nitroalkenes: Construction of Quaternary Carbon-Bearing Aldehydes under Solvent-Free Conditions

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 9 2009
    Chihliang Chang
    Abstract A novel pyrrolidine-camphor organocatalyst 3 was designed, synthesized and proven to be an efficient catalyst for the asymmetric Michael reaction. Treatment of ,,,-disubstituted aldehydes with ,-nitroalkenes in the presence of 20,mol% organocatalyst 3 and 20,mol% benzoic acid under solvent-free conditions provided the desired Michael product possessing an all-carbon quaternary center with high chemical yields (up to 99% yield) and high levels of enantioselectivities (up to 95% ee). [source]

    A Novel Cost-Effective Thiourea Bifunctional Organocatalyst for Highly Enantioselective Alcoholysis of meso -Cyclic Anhydrides: Enhanced Enantioselectivity by Configuration Inversion

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 4 2009
    Su-Xi Wang
    Abstract A novel inexpensive thiourea bifunctional organocatalyst which can promote the highly enantioselective (up to 95% ee) alcoholysis of meso -cyclic anhydrides has been developed. Computational studies on the catalytic process as well as a synthetic application of this new catalyst are also presented. [source]

    Enantioselective Aza-Henry Reaction with Acyclic Guanidine-Thiourea Bifunctional Organocatalyst

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 3 2009
    Keisuke Takada
    Abstract A highly enantioselective aza-Henry reaction of imines with nitromethane was achieved with a reactive guanidine-thiourea bifunctional organocatalyst affording ,-nitroamines with high enantioselectivity (up to 96% ee). The diastereo- and enantioselective version of this reaction with nitroalkanes also proceeded selectively (up to 99:1 dr with 99% ee). [source]

    A Novel Bis-Thiourea Organocatalyst for the Asymmetric Aza-Henry Reaction

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2008
    Constantinos Rampalakos
    Abstract A novel bis-thiourea/2,2,-diaminobinaphthalene (BINAM)-based catalyst for the asymmetric aza-Henry reaction has been developed. This catalyst promotes the reaction of N -Boc imines with nitroalkanes to afford ,-nitroamines with good yields and high enantioselectivities. This catalyst has the advantage that it can be prepared in a single step from commercially available materials. A model is proposed for the catalyst action where both components of the reaction are activated simultaneously by hydrogen bonding. Regardless of the mechanism, the success of the present catalyst demonstrates the potential of bis-thioureas as an interesting class of relatively unexplored catalysts. [source]

    1,3,5-Triaza-7-phosphaadamantane (PTA): A Practical and Versatile Nucleophilic Phosphine Organocatalyst

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 11-12 2007
    Xiaofang Tang
    Abstract In this paper, the air-stable and readily available 1,3,5-triaza-7-phosphaadmantane (PTA) is reported as a practical and versatile nucleophilic phosphine organocatalyst. Under the mediation of 15,30 mol,% of PTA, various electrophiles like aldehydes and imines readily undergo the Morita,Baylis,Hillman reactions with a variety of activated olefins, giving the corresponding adducts in high yields. In the phosphine-catalyzed [3+2] cycloaddition reaction of 4-substituted 2,3-butadienoates with N -tosylimines, PTA is also proven to be a comparable catalyst as tributylphosphine (PBu3). By systematic comparison with other structurally similar N,P catalysts, it is concluded that the superiority of PTA in the above nucleophilic catalysis is attributable to its comparable nucleophilicity with that of trialkylphosphines. The feasibility to use PTA as an alternative catalyst in place of the air-sensitive trialkylphosphines is also discussed. [source]

    Entropy-Controlled Catalytic Asymmetric 1,4-Type Friedel,Crafts Reaction of Phenols Using Conformationally Flexible Guanidine/Bisthiourea Organocatalyst,

    ANGEWANDTE CHEMIE, Issue 40 2010
    Dr. Yoshihiro Sohtome
    Soft Skills: Organische Verbindungen mit flexibler Konformation (,weiche" Organokatalysatoren) vermitteln die Titelreaktion. Sie sind in der Lage, Prozesse durch die unterschiedlichen Aktivierungsentropien (,,S,S,R) der reaktiven Intermediate zu steuern, und ergeben hohe Stereoselektivitäten, ohne dass eine Abstimmung der Reaktionstemperaturen erforderlich wäre (siehe Schema). Ar=3,5-(CF3)2C6H3. [source]

    ChemInform Abstract: C3 -Symmetric Chiral Trisimidazoline: Design and Application to Organocatalyst.

    CHEMINFORM, Issue 29 2010
    Kenichi Murai
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: A Highly Selective, Polymer-Supported Organocatalyst for Michael Additions with Enzyme-Like Behavior.

    CHEMINFORM, Issue 18 2010
    Esther Alza
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: A Chiral Bifunctional Sulfonamide as an Organocatalyst: Alcoholysis of ,-Symmetric Cyclic Dicarboxylic Anhydrides.

    CHEMINFORM, Issue 17 2010
    Takashi Honjo
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Valine-Derived Phosphinothiourea as Organocatalyst in Enantioselective Morita,Baylis,Hillman Reactions of Acrylates with Aromatic Aldehydes.

    CHEMINFORM, Issue 9 2010
    Jing-Jing Gong
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: A Solid-Supported Organocatalyst for Highly Stereoselective, Batch, and Continuous-Flow Mannich Reactions.

    CHEMINFORM, Issue 6 2010
    Esther Alza
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: o-Benzenedisulfonimide as a Powerful and Recyclable Organocatalyst for the Nazarov Reaction.

    CHEMINFORM, Issue 49 2009
    Margherita Barbero
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: A Designer Axially Chiral Amino Sulfonamide as an Efficient Organocatalyst for Direct Asymmetric anti-Selective Mannich Reactions and syn-Selective Cross-Aldol Reactions.

    CHEMINFORM, Issue 46 2009
    Taichi Kano
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Enantioselective Aziridination Reaction of ,,,-Unsaturated Aldehydes Using an Organocatalyst and tert-Butyl N-Arenesulfonyloxycarbamates.

    CHEMINFORM, Issue 40 2009
    Hiromi Arai
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Magnetic Nanoparticle-Supported Glutathione: A Conceptually Sustainable Organocatalyst.

    CHEMINFORM, Issue 34 2009
    Vivek Polshettiwar
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Ionic Liquid Supported (ILS) (S)-Pyrrolidine Sulfonamide, a Recyclable Organocatalyst for the Highly Enantioselective Michael Addition to Nitroolefins.

    CHEMINFORM, Issue 27 2009
    Bukuo Ni
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Enantioselective Aza-Henry Reaction with Acyclic Guanidine-Thiourea Bifunctional Organocatalyst.

    CHEMINFORM, Issue 26 2009
    Keisuke Takada
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: N-Tosyl-(Sa)-binam-L-prolinamide as Highly Efficient Bifunctional Organocatalyst for the General Enantioselective Solvent-Free Aldol Reaction.

    CHEMINFORM, Issue 15 2009
    Gabriela Guillena
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Enantioselective Epoxidation of ,,,-Enones Promoted by (1R,3S,4S)-2-Azanorbornyl-3-methanol as an Organocatalyst.

    CHEMINFORM, Issue 3 2009
    Jun Lu
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: A Novel Bis-Thiourea Organocatalyst for the Asymmetric Aza-Henry Reaction.

    CHEMINFORM, Issue 50 2008
    Constantinos Rampalakos
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Highly Enantioselective Strecker Reaction of Ketoimines Catalyzed by an Organocatalyst from (S)-BINOL and L-Prolinamide.

    CHEMINFORM, Issue 37 2008
    Zongrui Hou
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Use of (S)-5-(2-Methylpyrrolidin-2-yl)-1H-tetrazole as a Novel and Enantioselective Organocatalyst for the Aldol Reaction.

    CHEMINFORM, Issue 21 2008
    Sok-Teng Tong
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: Prolinol tert-Butyldiphenylsilyl Ether as Organocatalyst for the Asymmetric Michael Addition of Cyclohexanone to Nitroolefins.

    CHEMINFORM, Issue 5 2008
    Fengying Liu
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

    ChemInform Abstract: A New Organocatalyst for Friedel,Crafts Alkylation of 2-Naphthols with Isatins: Application of an Organo-Click Strategy for the Cascade Synthesis of Highly Functionalized Molecules.

    CHEMINFORM, Issue 5 2008
    Dhevalapally B. Ramachary
    Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]