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An efficient, solvent-free ball-milling protocol for the asymmetric aldol reaction between cyclohexanone and cyclopentanone with various aromatic aldehydes …
ChemInform Abstract: Efficient Ball-Mill Procedure in the ′Green′ Asymmetric Aldol Reaction Organocatalyzed by (S)-Proline-Containing Dipeptides in the Presence of …
Semantic Scholar extracted view of "Efficient ball-mill procedure in the 'green' asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the presence of water" by José G. Hernández et al. ... @article{Hernndez2011EfficientBP, title={Efficient ball-mill procedure in the 'green' asymmetric aldol reaction ...
Efficient ball-mill procedure in the 'green' asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the presence of water ... -2, in the asymmetric aldol reaction between cyclohexanone and acetone with various aromatic aldehydes under … Expand. 148. Save. Solvent-free asymmetric direct aldol reactions ...
Anti-aldol products with up to >99 % enantiomeric excess (ee) have been obtained by proline catalysis in excellent yields under experimentally simple solvent-free conditions. Efficient mixing of all the components is accomplished by applying a mechanochemical technique (ball milling). The catalys …
Highly efficient asymmetric aldol reaction in brine using a fluorous sulfonamide organocatalyst. Organic & Biomolecular Chemistry 2012, 10 (11), 2209. DOI: 10.1039/c2ob06955e. ... Efficient ball-mill procedure in the 'green' asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the presence of water. …
Efficient ball-mill procedure in the 'green' asymmetric aldol reaction ... A highly efficient asymmetric organocatalytic aldol reaction in a ball mill. Chem. Eur. J., 13 (2007 ... Liu J., Dodda R., Zhao C.-G. C 2-Symmetric bisprolinamide as a highly efficient catalyst for direct aldol reaction. Org. Lett., 7 (2005), pp. 5321-5323. CrossRef ...
The direct asymmetric aldol reactions of equivalent molar amounts of aldehydes and ketones were carried out at -20 degrees C over alkaline Al(2)O(3) with 20 mol % of Pro-Trp as catalyst and 20 mol ...
Efficient ball-mill procedure in the 'green' asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the presence of water
Highly efficient asymmetric aldol reaction in brine using a fluorous sulfonamide organocatalyst. Organic & Biomolecular Chemistry 2012, 10, 2209. DOI: 10.1039/c2ob06955e. ... Efficient ball-mill procedure in the 'green' asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the presence of water. ...
Efficient ball-mill procedure in the 'green' asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the presence of water. José G. Hernández E. …
Abstract. Mechanochemical approach in organic synthesis is of growing interest because of its wide applications towards green methodologies. Ball-milling has been fruitfully utilized in the ...
Chem. Eur. J. 2007 Bolm C.A Highly Efficient Asymmetric OrganocatalyticAldol Reaction in a Ball Mill.ChemEurJ2007; 13 4710-4722.2014 12 2 Hernández JG Juaristi E Efficient ball mill procedure in the green asymmetric aldol reaction organocatalyzed by S proline containing dipeptides in the presence of water Tetrahedron 2011 67 36 6953–6959.
General Procedure for the Preparation of the Deep Eutectic Solvents (DES) ... A Highly Efficient Asymmetric Organocatalytic Aldol Reaction in a Ball Mill. Chem. Eur. J. 2007, 13, 4710–4722. [Google Scholar ... Zheng, X.; Wang, Y. A Green and Efficient Asymmetric Aldol Reaction Catalyzed by a Chiral Anion Modified Ionic …
Semantic Scholar extracted view of "Efficient ball-mill procedure in the 'green' asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the …
Asymmetric aldol reactions are a powerful method for the construction of carbon-carbon bonds in an enantioselective fashion. Historically this reaction has been performed in a stoichiometric fashion to control the various aspects of chemo-, diastereo-, regio- and enantioselectivity, however, a more atom economical approach would unite high …
The mechanochemical technique of ball milling has been applied to the asymmetric opening of meso-anhydrides, mediated by the cinchona alkaloid quinidine. A simple workup procedure affords the products, optically active dicarboxylic acid monoesters, in high yields, with up to 64% ee. With most substrates no column …
This simple new concept has totally captured the attention of much of the organic chemistry community in the last decade. 1 For instance, the fact that organocatalysis prevents the use of a metal means that organocatalytic processes fulfill one of the guidelines of green chemistry, where the design of safe chemical process is a key …
This simple new concept has totally captured the attention of much of the organic chemistry community in the last decade. 1 For instance, the fact that …
The use of protonated l-prolinethioamide instead of the free base derivative 1 as the organocatalyst for the direct aldol addition has a profound and appreciable effect on both the yield and the stereochemical course of the reaction. 4-Nitrobenzaldehyde (2) reacts with acetone in the presence of the protonated catalyst 1.TFA, affording aldol ...
Ball milling: an efficient and green approach for asymmetric organic syntheses | Semantic Scholar. DOI: 10.1039/c9gc03414e. Corpus ID: 213654565. Ball …
Efficient ball-mill procedure in the 'green' asymmetric ... Indeed, in aldol reaction catalyzed by proline resi- obtained in high yields (up to 94%) and good enantioselectivities dues embedded in a hydrophobic environment, water has dem- (up to 97% ee).17a In addition, Li and co-workers examined di- onstrated to play an important role in …
Efficient ball-mill procedure in the 'green' asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the presence of water - …
A chiral anion modified ionic liquid derived from L -proline proves as a green and efficient asymmetric organocatalyst for direct asymmetric aldol reactions in [BMIm]BF 4 at room temperature. The corresponding aldol products with moderate to good isolated yields (up to 99 %), anti-diastereoselectivities (up to 97:3), and excellent enantioselectivities (up to 99 …
ChemInform Abstract: Efficient Ball-Mill Procedure in the ′Green′ Asymmetric Aldol Reaction Organocatalyzed by (S)-Proline-Containing Dipeptides in the Presence of Water. Article Sep 2011
Ball-milling Green chemistry Asymmetric aldol reaction abstract The organocatalytic activity of (S)-proline-based dipeptides 1aec has been evaluated in the asymmetric …
Abstract: Abstract The organocatalytic activity of (S)-proline-based dipeptides 1a–c has been evaluated in the asymmetric aldol reaction between representative ketones with …
The organocatalytic activity of the methyl ester of (S)-proline-(S)-phenylalanine, (S,S)-2, in the asymmetric aldol reaction between cyclohexanone and acetone with various aromatic aldehydes under solvent-free conditions in a ball mill has been evaluated. α,α-Dipeptide (S,S)-2 catalyzed the stereoselective formation of the …
Highly efficient asymmetric aldol reaction in brine using a fluorous sulfonamide organocatalyst. Organic & Biomolecular Chemistry 2012, 10 ... Efficient ball-mill procedure in the 'green' asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the presence of water. Tetrahedron 2011, 67 ...
Efficient ball-mill procedure in the 'green' asymmetric aldol reaction organocatalyzed by (S)-proline-containing dipeptides in the presence of water ... The organocatalytic activity of the methyl ester of (S)-proline-(S)-phenylalanine, (S,S)-2, in the asymmetric aldol reaction between cyclohexanone and acetone with various aromatic …
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