Enantioselective deprotonation of symmetrical epoxides was studied by using chiral lithium amide, prepared from (S)-2-(N,N-disubstituted aminomethyl)pyrrolidine and butyllithium. Chiral allylic alcohols were obtained with moderate to high enantiomeric excesses (ee’s) (41–92% ee) from several cyclic and acyclic epoxides employing lithium (S)-2-(1-pyrrolidinylmethyl)pyrrolidide in tetrahydrofuran (THF) in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU).
使用由(S)-2-(N,N-二取代
氨基甲基)
吡咯烷和丁基
锂制备的手性
锂胺,研究了对称
环氧化物的对映选择性去质子化反应。通过在
四氢呋喃(THF)中采用
锂(S)-2-(1-
吡咯啉甲基)
吡咯化
锂并加入
1,8-二氮杂双环[5.4.0]十一碳-7-烯(
DBU)的条件,从若干环状和非环状
环氧化物中获得了具有中等至高度对映体过剩(ee's)(41-92% ee)的手性
烯丙醇。