Di(methylimidazole)prolinol silyl ether catalyzed highly Michael addition of aldehydes to nitroolefins in water
Jianbin Wu1, Bukuo Ni, Allan D Headley
1Department of Chemistry, Texas A&M University-Commerce, Commerce, Texas 75429-3011, USA.
Abstract:
A new pyrrolidine-based organocatalyst for asymmetric reactions has been developed and shown to be a very effective catalyst for the Michael reaction involving various nitroolefins and aldehydes in water. This design is based on the introduction of a hydrophilic group into the pyrrolidine side chain. This catalyst, di(methylimidazole)prolinol silyl ether in combination with sodium bicarbonate as additive effectively catalyzed the Michael addition of aldehydes to nitroolefins in water as solvent in high yields and excellent enantioselectivities.
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