Asymmetric Michael reactions catalyzed by a highly efficient and recyclable quaternary ammonium ionic
Subrata K Ghosh1, Yupu Qiao, Bukuo Ni
1Department of Chemistry, Texas A&M University-Commerce, Commerce, TX 75429-3001, USA.
Abstract:
A novel ionic liquid-support organocatalyst, which contains the quaternary ammonium ion moiety, was recently developed and successfully applied to the asymmetric Michael reaction in the presence of a newly developed ionic liquid-supported (ILS) benzoic acid as co-catalyst. For the reactions studied, in which various aldehydes and nitroolefins were examined, excellent diastereo- and enantioselectivities were obtained with low catalyst loading. Also, the catalyst could be recycled for ten times without significant loss of enantioselectivity.
Related Concept Videos
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Conjugate Addition of Enolates: Michael Addition
Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
Cyclohexenones via Michael Addition and Aldol Condensation: The Robinson Annulation
Preparation of 1° Amines: Hofmann and Curtius Rearrangement Overview
Alkynes to Aldehydes and Ketones: Acid-Catalyzed Hydration
Analogous to alkenes, alkynes also undergo acid-catalyzed hydration. While the addition of water to an alkene gives an alcohol, hydration of alkynes produces different products such as aldehydes and ketones.


