Redox tuning of a direct asymmetric aldol reaction.
Presented herein is a redox tuning strategy for asymmetric aminocatalysis with a designed chiral ferrocenophane. Under redox control, the ferrocenophane catalyst efficiently catalyzes the asymmetric aldol reaction at room temperature with excellent yield and good stereoselectivity. Moreover, the redox-active ferrocene moiety also served as phase-tag to facilitate catalyst recovery and reuse. The catalyst can be reused for five cycles without much loss of activity. Ferrocenium of the oxidized ferrocenophane was proposed to serve as Lewis acidic site, thus accounting for the stereo control.
Henan Key Laboratory of Chemical Biology and Organic Chemistry, Key Laboratory of Applied Chemistry of Henan Universities, Department of Chemistry, Zhengzhou University, 75 Daxue North Road, Zhengzhou 450052 (China).
Qiying
Q
Zhang
Xiuling
X
Cui
Long
L
Zhang
Sanzhong
S
Luo
Hui
H
Wang
Yangjie
Y
Wu
aldol reaction; asymmetric catalysis; iron; organocatalysis; redox chemistry