反应 #674306

反应方程式

Ether

Ethyl chloroformate

4-(benzyloxy)cyclohexanecarbonitrile

LDA

→

ethyl 4-(benzyloxy)-1-cyanocyclohexanecarboxylate

收率 33.6%

溶剂

THF

反应条件

后处理

1. 1
   workup.STIRRINGThe solution was stirred at −78° C.
2. 2
   温度to warm to room temperature slowly
3. 3
   workup.STIRRINGstirred overnight
4. 4
   其他The reaction was quenched by addition of H2O (20 mL), HCl (1.0 N, 20 mL)
5. 5
   萃取It was then extracted with EtOAc (3×40 mL)
6. 6
   洗涤The combined organic solution was washed with brine (50 mL)
7. 7
   干燥dried over anhydrous Na2SO4
8. 8
   浓缩concentrated
9. 9
   其他to give pale yellow residue
10. 10
    workup.STIRRINGstirred for 5 min
11. 11
    过滤filtered
12. 12
    其他to remove the white solid
13. 13
    浓缩The ethereal solution was concentrated
14. 14
    其他to give the yellow oil which
15. 15
    其他was purified by CombiFlash (25 g silica gel column, EtOAc/Hexane: 0-20%)

实验过程

To a solution of 4-(benzyloxy)cyclohexanecarbonitrile (1.26 g, 5.85 mmol, 1.0 equiv) in THF (dry, 30 mL) was added a solution of LDA (3.95 mL, 2.0 M Heptane/THF/toluene, 1.35 equiv) dropwise at −78° C. under N2. The resulting yellow solution was stirred at −78° C. for 2 hrs. Ethyl chloroformate (2.79 mL, 29.26 mmol, 5.0 equiv) was then added by syringe dropwise. The solution was stirred at −78° C. and allowed to warm to room temperature slowly and stirred overnight. The reaction was quenched by addition of H2O (20 mL), HCl (1.0 N, 20 mL). It was then extracted with EtOAc (3×40 mL). The combined organic solution was washed with brine (50 mL), dried over anhydrous Na2SO4 and then concentrated to give pale yellow residue. Ether (40 mL) was added and stirred for 5 min, filtered to remove the white solid. The ethereal solution was concentrated to give the yellow oil which was purified by CombiFlash (25 g silica gel column, EtOAc/Hexane: 0-20%) to afford 565 mg (yield 33%) of ethyl 4-(benzyloxy)-1-cyanocyclohexanecarboxylate as a pale yellow oil.

来源