Catalytic asymmetric cyanosilylation of ketones by a chiral amino acid salt.
In this Communication, we describe the first highly enantioselective cyanosilylation of ketones catalyzed by simple chiral amino acid salt. A broad range of aromatic, alpha,beta-unsaturated, heterocyclic ketones catalyzed by l-phenylglycine sodium salt gave the corresponding trimethylsilyl ethers of cyanohydrins in 75-96% yields with 86-97% enantioselectivities. A catalytic cycle based on experimental phenomena and studies has been proposed to explain the origin of this activation. The reaction employed commercially available and fully recyclable catalysts and involves a simple experimental procedure.
Liu
Xiaohua
X
Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, P R China.
Qin
Bo
B
Zhou
Xin
X
He
Bin
B
Feng
Xiaoming
X