A Triazole Organocatalyst with Spiropyrrolidine Framework and its Application to the Catalytic Asymmetric Addition of Nitromethane to α,β-Unsaturated Aldehydes
A series of new water-compatible “spiropyrrolidine triazole” catalysts was designed and synthesized. The asymmetric Michael addition of nitromethane and α,β-unsaturatedaldehydes in an aqueous system was investigated to evaluate these new catalysts, and the resulting adducts were obtained with excellent enantioselectivity (up to 95.5% ee) and moderate to good yield (63–88%).
Asymmetric Michael Reaction of Acetaldehyde with Nitroolefins Catalyzed by Highly Water-Compatible Organocatalysts in Aqueous Media
作者:Yupu Qiao、Junpeng He、Bukuo Ni、Allan D. Headley
DOI:10.1002/adsc.201200215
日期:2012.10.8
A novel category of diarylprolinol silylether catalysts which contain different lengths of alkylamine tags, was designed and synthesized. These catalysts were used, along with benzoic acid as the co-catalyst, to catalyze the asymmetric Michael reaction of the highly reactive acetaldehyde with nitroolefins. For the reactions studied, this catalyticsystem exhibited high reactivity in brine without