Organoboron compounds in organic synthesis. 4. Asymmetric aldol reactions

Porcine pancreas lipase type II (PPL II) exhibited unnatural catalytic activity in direct asymmetric aldol reactions between cyclic ketones and aromatic or heteroaromatic aldehydes in acetonitrile in the presence of phosphate buffer. A wide range of substrates was accepted by the enzyme to afford the corresponding aldol products in low to high yields (10 - 98%), with moderate to excellent enantioselectivities (53 - 94% ee, for anti-isomers) and low to moderate diastereoselectivities (48/52 - 87/13 dr, anti/syn). This methodology expands the application of PPL II, and it might be developed into a potentially valuable method for sustainable organic synthesis.

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Polymer Supported Proline-Based Organocatalysts in Asymmetric Aldol Reactions: A Review

Current Organocatalysis ◽

10.2174/2213337209666220112094231 ◽

2022 ◽

Vol 09 ◽

Author(s):

Rubina Shajahan ◽

Rithwik Sarang ◽

Anas Saithalavi

Keyword(s):

Organic Synthesis ◽

Aldol Reaction ◽

Enantioselective Synthesis ◽

Aldol Reactions ◽

Reaction Conditions ◽

Asymmetric Aldol ◽

Bond Forming ◽

Recent Developments ◽

Potential Benefits ◽

Polymer Supported

The use of proline-based organocatalysts has acquired significant importance in organic synthesis, especially in enantioselective synthesis. Proline and its derivatives are proven to be quite effective chiral organocatalysts for a variety of transformations including the aldol reaction, which is considered as one of the important C-C bond forming reactions in organic synthesis. The use of chiral organocatalysts has several advantages over its metal-mediated analogues. Subsequently, a large number of highly efficient proline-based organocatalysts including polymer-supported chiral analogues have been identified for aldol reaction. The use of polymer-supported organocatalysts exhibited remarkable stability under the reaction conditions and offered the best results particularly in terms of its recyclability and reusability. These potential benefits along with its economic and green chemistry advantages have led to the search for many polymer-supported proline catalysts. In this review, recent developments in exploring various polymer immobilized proline-based chiral organocatalysts for asymmetric aldol reactions are described.

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(S)-5-prolylamide-triazole Organocatalyst for Direct Asymmetric Aldol Reactions

Current Organic Chemistry ◽

10.2174/1385272811317140011 ◽

2013 ◽

Vol 17 (14) ◽

pp. 1563-1568 ◽

Cited By ~ 4

Author(s):

Ling Liu ◽

Min-Na Gao ◽

Yang Li ◽

Zhen Li ◽

Liping Song ◽

...

Keyword(s):

Aldol Reactions ◽

Asymmetric Aldol

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ChemInform Abstract: Organocatalytic Asymmetric Aldol Reactions Mediated by a Cysteine-Derived Prolinamide.

ChemInform ◽

10.1002/chin.200848067 ◽

2008 ◽

Vol 39 (48) ◽

Author(s):

Ricardo S. Schwab ◽

Fabio Z. Galetto ◽

Juliano B. Azeredo ◽

Antonio L. Braga ◽

Diogo S. Luedtke ◽

...

Keyword(s):

Aldol Reactions ◽

Asymmetric Aldol

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Synthesis and evaluation of (S)-proline-containing dipeptidic organocatalysts bound to MBHA resin in asymmetric aldol reactions

Tetrahedron Letters ◽

10.1016/j.tetlet.2015.09.062 ◽

2015 ◽

Vol 56 (44) ◽

pp. 6047-6051 ◽

Cited By ~ 13

Author(s):

Elizabeth Machuca ◽

Giovanna Granados ◽

Bruno Hinojosa ◽

Eusebio Juaristi

Keyword(s):

Aldol Reactions ◽

Asymmetric Aldol

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Intramolecular hydrogen bonding guides a cationic amphiphilic organocatalyst to highly stereoselective aldol reactions in water

RSC Advances ◽

10.1039/c5ra12135c ◽

2015 ◽

Vol 5 (77) ◽

pp. 62331-62335 ◽

Cited By ~ 10

Author(s):

Ángel M. Valdivielso ◽

Alba Catot ◽

Ignacio Alfonso ◽

Ciril Jimeno

Keyword(s):

Hydrogen Bonding ◽

Intramolecular Hydrogen Bonding ◽

Structural Motif ◽

Aldol Reactions ◽

Asymmetric Aldol ◽

Neutral Ph ◽

Intramolecular Hydrogen

A novel amphiphilic acylguanidine organocatalyst using intramolecular hydrogen bonding as a key structural motif is efficient for asymmetric aldol reactions of ketones in water at neutral pH.

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