Highly Enantioselective Conjugate Addition of Cyclic Diketones to β,γ-Unsaturated α-Ketoesters Catalyzed by an N,N′-Dioxide-Cu(OTf)2 Complex
作者:Zhenhua Dong、Juhua Feng、Xuan Fu、Xiaohua Liu、Lili Lin、Xiaoming Feng
DOI:10.1002/chem.201002687
日期:2011.1.24
Copper‐catalyzed conjugate addition: A highly enantioselective conjugate addition of cyclic diketones to β,γ‐unsaturated α‐ketoesters was achieved by using a two‐carbon‐linked N,N′‐dioxide‐Cu(OTf)2 complex. Excellent yields (up to 99 %) and enantioselectivities (up to 99 % ee) were obtained with 2 mol % catalyst loading (see scheme). By using this method, adducts could be easily transformed into hexahydroquinolines
铜催化的共轭物加成:通过使用两个碳连接的N,N'-二氧化物-Cu(OTf)2络合物,将环状二酮高度对映选择性共轭加成到β,γ-不饱和的α-酮酸酯上。在催化剂负载量为2 mol%的情况下,可获得极佳的收率(高达99%)和对映选择性(高达99% ee)(请参阅方案)。通过使用这种方法,加合物可以很容易地转化为六氢喹啉。反应也可以按比例放大至克量,而不会损失收率或对映选择性。