Asymmetric Michael addition of thiols to β-nitrostyrenes using a novel phenylpyrrolidine-based urea catalyst
作者:Souichirou Kawazoe、Kazuki Yoshida、Yuichi Shimazaki、Takeshi Oriyama
DOI:10.1016/j.tetlet.2014.11.116
日期:2015.1
The catalyst 1-[(3R,4S)-1-benzyl-4-phenyl-pyrrolidin-3-yl]-3-[3,5-bis(trifluoromethyl)phenyl]urea (8) designed based on 1-[(3R)-1-benzylpyrrolidin-3-yl]-3-[3,5-bis(trifluoromethyl)phenyl]thiourea (4) and 1,3-bis[(3R,4S)-1-benzyl-4-phenylpyrrolidin-3-yl]urea (7) exhibited potent catalytic activity for the asymmetric Michael addition of thiols to β-nitrostyrenes. A mere 2 mol % of the catalyst afforded
基于1-的设计的催化剂1-[(3 R,4 S)-1-苄基-4-苯基-吡咯烷基-3-基] -3- [3,5-双(三氟甲基)苯基]脲(8) [(3 R)-1-苄基吡咯烷-3-基] -3- [3,5-双(三氟甲基)苯基]硫脲(4)和1,3-双[(3 R,4 S)-1-苄基-4-苯基吡咯烷烃-3-基]脲(7)对硫醇向β-硝基苯乙烯的不对称迈克尔加成反应显示出有效的催化活性。仅仅2 mol%的催化剂以高达93%ee的高收率提供了2-硝基-1-苯基乙基硫醚。