تفاعل #1447082

معادلة التفاعل

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

المذيبات

THF

THF

THF

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةthe 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
   درجة الحرارةwarmed to RT
5. 5
   أخرىAfter separation of the phases
6. 6
   أخرىthe organic phase was dried
7. 7
   أخرىthe solvent was removed
8. 8
   أخرىThe residue was purified chromatographically (SiO2, cyclohexane/ethyl acetate)
9. 9
   أخرىThis 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

الإجراء التجريبي

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.

المصدر