Asymmetric Organocatalytic Cascade Michael/Hemiketalization/Retro-Aldol Reaction of 2-[(<i>E</i>)-2-Nitrovinyl]phenols with 2,4-Dioxo-4-arylbutanoates: A Convenient Access to Chiral α-Keto Esters
作者:Yunting Liu、Youming Wang、Haibin Song、Zhenghong Zhou、Chuchi Tang
DOI:10.1002/adsc.201300552
日期:2013.9.16
unprecedented organocatalytic enantioselective cascade Michael/hemiketalization/retro‐aldol reaction of 2‐[(E)‐2‐nitrovinyl]phenols and 2,4‐dioxo‐4‐arylbutanoates is described. With a bifunctional squaramide catalyst incorporating (1R,2R)‐1,2‐diphenylethane‐1,2‐diamine, the reactions afford products in 75–99% yields with 80–98% ee. This process provides an enantioselective pathway for the synthesis of chiral
描述了2-[((E))-2-硝基乙烯基]苯酚与2,4-二氧代-4-芳基丁酸酯的史无前例的有机催化对映选择性级联迈克尔/半缩酮化/复古-羟醛反应。使用结合了(1 R,2 R)-1,2-二苯乙烷-1,2-二胺的双官能方胺催化剂,该反应可提供75-99%的收率和80-98%ee的产物。该过程为手性α-酮酯,3-芳基脯氨酸衍生物的前体,δ-氨基α-酮酸或环状α-酮内酰胺的合成提供了对映选择性的途径。