Diastereo- and enantioselective conjugate addition of α-keto esters to nitroalkenes: Complete switch in the enantioselectivity by tuning the metal center or rigidity of the ligand
作者:Xiangning Chen、Han Zhou、Hanmin Huang
DOI:10.1016/s1872-2067(14)60199-6
日期:2015.1
been developed to control the dual enantioselectivity of the conjugate addition of α-keto esters to nitroalkenes. The use of the chiral diamine (1 S ,1’ S )-1,1′-biisoindoline as a chiral ligand with either (Cu(OAc) 2 ·H 2 O or Ni(OAc) 2 ·4H 2 O as the catalyst provide facile access to the respective enantiomers resulting from the conjugate addition reaction with high levels of enantioselectivity (94%
摘要 已经开发了一系列有效的催化系统来控制 α-酮酯与硝基烯烃共轭加成的双重对映选择性。使用手性二胺 (1 S ,1' S )-1,1'-双异二氢吲哚作为手性配体,以 (Cu(OAc) 2 ·H 2 O 或 Ni(OAc) 2 ·4H 2 O 为催化剂)以高水平的对映选择性(94% ee vs 93% ee)轻松获得由共轭加成反应产生的各个对映异构体。此外,使用 Cu(OAc) 2 ·H 2 O 作为金属中心允许对映选择性通过调节手性二胺配体的刚性(94% ee vs 94% ee)来切换共轭加成反应。