Highly Enantioselective Michael Addition of Cyclic 1,3-Dicarbonyl Compounds to β,γ-Unsaturated α-Keto Esters
作者:Xing-Kuan Chen、Chang-Wu Zheng、Sheng-Li Zhao、Zhuo Chai、Ying-Quan Yang、Gang Zhao、Wei-Guo Cao
DOI:10.1002/adsc.201000045
日期:——
A highlyenantioselectiveMichaeladdition of cyclic 1,3‐dicarbonyl compounds to β,γ‐unsaturated α‐keto esters catalyzed by amino acid‐derived thiourea‐tertiary‐amine catalysts is presented. Using 5 mol% of a novel tyrosine‐derived thiourea catalyst, a series of chiral coumarin derivatives were obtained in excellent yields (up to 99%) and with up to 96% ee under very mild conditions within a short