BF3·Et2O catalyzed diastereoselective nucleophilic reactions of 3-silyloxypiperidine N,O-acetal with silyl enol ether and application to the asymmetric synthesis of (+)-febrifugine

  title={BF3·Et2O catalyzed diastereoselective nucleophilic reactions of 3-silyloxypiperidine N,O-acetal with silyl enol ether and application to the asymmetric synthesis of (+)-febrifugine},
  author={Ru-Cheng Liu and W. Huang and Jing-yi Ma and Bang-Guo Wei and G. Lin},
  journal={Tetrahedron Letters},
Abstract The asymmetric BF 3 ·Et 2 O catalyzed nucleophilic reactions of 3-silyloxypiperidine N , O -acetal 10 with silyl enol ethers derived from ketones are described. (+)-Febrifugine 1 , an antimalarial alkaloid, was successfully synthesized based on this nucleophilic substitution. In addition, N , O -acetal 10 was synthesized from l -benzyl glutamate in 11 steps. 
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