反应 #1447082

反应方程式

acrolein

lithium diisopropylamide

ethyl [(1-methyl-3-trifluoromethyl-1H-pyrazole-4-carbonyl)amino]acetate

NH4Cl

→

Ethyl 3-hydroxy-2-[(1-methyl-3-trifluoromethyl-1H-pyrazole-4-carbonyl)amino]pent-4-enoate

溶剂

THF

THF

THF

反应条件

后处理

1. 1
   温度the mixture was cooled to −78° C.
2. 2
   workup.ADDITIONwere added dropwise
3. 3
   workup.STIRRINGAfter 2 h of stirring at −78° C.
4. 4
   温度warmed to RT
5. 5
   其他After separation of the phases
6. 6
   其他the organic phase was dried
7. 7
   其他the solvent was removed
8. 8
   其他The residue was purified chromatographically (SiO2, cyclohexane/ethyl acetate)
9. 9
   其他This gave 1.65 g (40% of theory) of the title compound as a colorless solid (about 1:1 diastereomer mixture) which was used without further purification

实验过程

At −50° C., 3.45 g (12.4 mmol) of ethyl [(1-methyl-3-trifluoromethyl-1H-pyrazole-4-carbonyl)amino]acetate dissolved in THF were added dropwise to 18.5 ml (37.0 mmol) of a 2M solution of lithium diisopropylamide in THF/heptanelethylbenzene. After 1.5 h of stirring at −50° C., the mixture was cooled to −78° C. and 0.83 g (14.8 mmol) of acrolein dissolved in THF were added dropwise. After 2 h of stirring at −78° C., the mixture was hydrolyzed with sat. NH4Cl solution and warmed to RT. After separation of the phases, the organic phase was dried and the solvent was removed. The residue was purified chromatographically (SiO2, cyclohexane/ethyl acetate). This gave 1.65 g (40% of theory) of the title compound as a colorless solid (about 1:1 diastereomer mixture) which was used without further purification.

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