Chiral bifunctional squaramide catalyzed asymmetric tandem Michael-cyclization reaction: efficient synthesis of optically active 2-amino-4H-chromene-3-carbonitrile derivatives
作者:Keling Hu, Aidang Lu, Youming Wang, Zhenghong Zhou*, Chuchi Tang
關(guān)鍵字:Chiral Squaramide, Tandem Michael-cyclization, Asymmetric Catalysis
論文來源:期刊
具體來源:Tetrahedron Asymmetry
發(fā)表時間:2013年
We have developed an efficient bifunctional squaramide catalyst for the asymmetric tandem Michael addition–cyclization of malononitrile to functionalized nitroolefins. This organocatalytic asymmetric reaction provides convenient and valuable access to highly functionalized 2-amino-4H-chromene derivatives, which possess important biological activities, in good yields with moderate to high enantioselectivities (up to 95% ee).