Amide groups switch selectivity: C-H trifluoromethylation of α,β-unsaturated amides and subsequent asymmetric transformation.
The first direct C-H β-trifluoromethylation of unsubstituted or α-alkyl-substituted α,β-unsaturated carbonyl compounds under metal-free conditions was realized with excellent regio- and stereoselectivity as well as a very broad substrate scope. Both olefinic and allylic trifluoromethylation products are accessible with high selectivities by altering the substrate substitutions. The resultant olefinic products, namely (E)-β-trifluoromethyl (CF3) α,β-unsaturated hydroxamic acid derivatives, served as acceptors in organocatalytic asymmetric Michael addition reactions to give hydroxamic acid derivatives bearing a chiral CF3-substituted stereocenter with high enantioselectivities.
Department of Chemistry, South University of Science and Technology of China , Shenzhen, 518055, P. R. China.
Lei
L
Li
Jing-Yao
JY
Guo
Xing-Guo
XG
Liu
Su
S
Chen
Yong
Y
Wang
Bin
B
Tan
Xin-Yuan
XY
Liu