Asymmetric 1,4-Michael Addition Reactions Catalyzed by a Cinchona Alkaloid Derived Primary Amine: A Theoretical Investigation of the Reaction Mechanism and Enantioselectivity

2013 ◽  
Vol 2013 (9) ◽  
pp. 1706-1715 ◽  
Author(s):  
Zhishan Su ◽  
Hai Whang Lee ◽  
Chan Kyung Kim
Keyword(s):  
Reaction Mechanism ◽  
Theoretical Investigation ◽  
Michael Addition ◽  
Primary Amine ◽  
Cinchona Alkaloid ◽  
Addition Reactions

Cinchona alkaloid-based chiral catalysts act as highly efficient multifunctional organocatalysts for the asymmetric conjugate addition of malonates to nitroolefins

2015 ◽  
Vol 13 (40) ◽  
pp. 10216-10225 ◽  
Author(s):  
Veeramanoharan Ashokkumar ◽  
Ayyanar Siva
Keyword(s):  
Michael Addition ◽  
Quaternary Ammonium ◽  
Conjugate Addition ◽  
Quaternary Ammonium Salts ◽  
Cinchona Alkaloid ◽  
Ammonium Salts ◽  
Addition Reactions ◽  
Chiral Catalysts ◽  
Reaction Conditions ◽  
Highly Efficient

New pentaerythritol tetrabromide based chiral quaternary ammonium salts have been prepared and used as organocatalysts for enantioselective Michael addition reactions between various nitroolefins and Michael donors under mild reaction conditions with very good chemical yields and ee's.

scholarly journals Novel Selenoureas Based on Cinchona Alkaloid Skeleton: Synthesis and Catalytic Investigations

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 600
Author(s):  
Mariola Zielińska-Błajet ◽  
Joanna Najdek
Keyword(s):  
Michael Addition ◽  
Catalytic Performance ◽  
Cinchona Alkaloid ◽  
Addition Reactions ◽  
Efficient Approach ◽  
Mild Conditions ◽  
Asymmetric Michael Addition

An efficient approach to the synthesis of chiral selenoureas consisting of Cinchona alkaloid scaffolds was described. The new selenoureas were assessed as bifunctional organocatalysts in the asymmetric Michael addition reactions under mild conditions. The best results were obtained for selenoureas bearing the 4-fluorophenyl group. These catalysts promoted the reactions with enantioselectivities of up to 96% ee. Additionally, the catalytic performance of the thiourea and selenourea counterpart was compared.

Deracemizing organocatalyzed Michael addition reactions of 2-(arylthio)cyclobutanones with β-nitrostyrenes

2016 ◽  
Vol 14 (13) ◽  
pp. 3394-3403 ◽  
Author(s):  
Alberto Luridiana ◽  
Angelo Frongia ◽  
David J. Aitken ◽  
Regis Guillot ◽  
Giorgia Sarais ◽  
...  
Keyword(s):  
Michael Addition ◽  
Primary Amine ◽  
Addition Reactions

Organocatalyzed Michael addition reactions of 2-(arylthio)cyclobutanones with trans-β-nitrostyrenes have been carried out using a bifunctional thiourea-primary amine catalyst, providing diastereoisomerically and enantiomerically enriched 2-alkyl-2-(arylthio)cyclobutanones.

ChemInform Abstract: Cinchona Alkaloid Catalyzed Sulfa-Michael Addition Reactions Leading to Enantiopure β-Functionalized Cysteines.

ChemInform ◽  
2016 ◽  
Vol 47 (11) ◽  
pp. no-no
Author(s):  
Arjen C. Breman ◽  
Suze E. M. Telderman ◽  
Roy P. M. van Santen ◽  
Jamie I. Scott ◽  
Jan H. van Maarseveen ◽  
...  
Keyword(s):  
Michael Addition ◽  
Cinchona Alkaloid ◽  
Addition Reactions

Ligand-Enabled γ-C(sp3)–H Olefination of Free Carboxylic Acids

2020 ◽  
Author(s):  
Kiron Kumar Ghosh ◽  
Alexander Uttry ◽  
Francesca Ghiringhelli ◽  
Arup Mondal ◽  
Manuel van Gemmeren
Keyword(s):  
Reaction Mechanism ◽  
Carboxylic Acids ◽  
Michael Addition ◽  
Kinetic Studies ◽  
Wide Range ◽  
Palladium Catalyzed

We report the ligand enabled C(sp3)–H activation/olefination of free carboxylic acids in the γ-position. Through an intramolecular Michael-addition, δ-lactones are obtained as products. Two distinct ligand classes are identified that enable the challenging palladium-catalyzed activation of free carboxylic acids in the γ-position. The developed protocol features a wide range of acid substrates and olefin reaction partners and is shown to be applicable on a preparatively useful scale. Insights into the underlying reaction mechanism obtained through kinetic studies are reported.<br>

Thia-Michael Addition Reactions in Water Using 3-[Bis(Alkylthio) Methylene] Pentane-2,4-Diones as Odorless and Efficient Thiol Equivalents

2007 ◽  
Vol 4 (4) ◽  
pp. 281-284 ◽  
Author(s):  
Yanyan Chai ◽  
Dewen Dong ◽  
Yan Ouyang ◽  
Yongjiu Liang ◽  
Yan Wang ◽  
...  
Keyword(s):  
Michael Addition ◽  
Addition Reactions
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