Highly enantio- and diastereoselective synthesis of alpha-trifluoromethyldihydropyrans using a novel bifunctional piperazine-thiourea catalyst.
The first enantioselective Michael addition of alpha-cyanoketones to alpha,beta-unsaturated trifluoromethyl ketones using a novel piperazine-thiourea catalyst was described. The resulting alpha-trifluoromethyldihydropyrans were obtained in high yields and with up to 95% ee within a short reaction time. A useful transformation of the chiral adduct was also illustrated.
Li
Peng
P
Key Laboratory of Organofluorine Chemistry and Key Laboratory of Modern Synthetic Organic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu, Shanghai, 200032, China.
Chai
Zhuo
Z
Zhao
Sheng-Li
SL
Yang
Ying-Quan
YQ
Wang
Hai-Feng
HF
Zheng
Chang-Wu
CW
Cai
Yue-Peng
YP
Zhao
Gang
G
Zhu
Shi-Zheng
SZ