Реакция #1447082

Уравнение реакции

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

Растворители

THF

THF

THF

Условия реакции

Обработка

1. 1
   Температураthe 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
   Температураwarmed to RT
5. 5
   ДругоеAfter separation of the phases
6. 6
   Другоеthe organic phase was dried
7. 7
   Другоеthe solvent was removed
8. 8
   ДругоеThe residue was purified chromatographically (SiO2, cyclohexane/ethyl acetate)
9. 9
   ДругоеThis 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

Методика

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.

Источник