做一个反应（见附件），按照文献的方法（一模一样），之前可以做成功，最近
重复了好多次，却怎么也得不到产物，更换了各种
试剂 都不行，各位大侠有没有经验指点非常感谢
(2S.3Rl-EthyI 2-Methyl-3-(tosylamino)pentanonfe (12). To a suspension of CuI (2.33 g, 12.2. mmol) in dry
THF (25 ml), stirred at -78" under N2, was added 1 . 5 ~M eLi in Et,O (15.27 ml, 22.9 mmol). The resulting
suspension was briefly warmed to 0" to dissolve solids and then recooled to -78". Next, the flask was immersed in
an EtOH bath at -30", and a soh. of crude 11 (1.074 g, 2.53 mmol) in dry THF (25 ml) was added to the clear
brown soln. The soln. was stirred at -2OO for 5 h at which time sat. aq. NH4CI soh. was added cautiously. After
warming to r.t., H,O (40 ml) was added, the mixture acidified, then neutralized with aq. NaHCO, soln., filtered by
suction, and extracted with AcOEt (4 x 15 ml). The combined org. phase was dried (Na2S04) and evaporated and
the crude oil (0.917 g) purified by FC (31 x 2 cm, hexane/AcOEt 1:l):
QQ图片20190306214612.png
