Reaktion #1181094

Reaktionsgleichung

cyclobutanone

BF3

NH4Cl

butyllithium

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

hexamethyldisilazane

→

Ethyl(1-hydroxycyclobutyl)-[(3-trifluoromethyl-1H-pyrazole-4-carbonyl)amino]-acetate

Lösungsmittel

THF

hexane

THF

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwere added dropwise
2. 2
   workup.ADDITIONwere added dropwise
3. 3
   workup.STIRRINGthe mixture was stirred at −78° C. for 2 h, at −50° C. for 1 h and at 0° C. for 1 h
4. 4
   workup.STIRRINGthe mixture was stirred for 30 min
5. 5
   SonstigeThe organic phase was separated off
6. 6
   Sonstigethe solvents were removed under reduced pressure
7. 7
   SonstigeThis gave 9.88 g (100%) of colorless crystals which were reacted without further purification

Vorschrift

23.0 ml of hexamethyldisilazane (mmol) were dissolved in 200 ml of THF, and 46 ml of 2.5M (115 mmol) of butyllithium solution in hexane were added dropwise at −78° C. After 30 min, 7.90 g (22.3 mmol) of ethyl [(1-methyl-3-trifluoromethyl-1H-pyrazole-4-carbonyl)amino]acetate, dissolved in 50 ml of THF, were added dropwise, and the mixture was stirred at −78° C. for 1.5 h. 3.0 g (42.8 mmol) of cyclobutanone and 4.14 g (29.2 mmol) of BF3-etherate, dissolved in 50 ml of THF, were added dropwise, and the mixture was stirred at −78° C. for 2 h, at −50° C. for 1 h and at 0° C. for 1 h. 100 ml of saturated NH4Cl solution were added dropwise, and the mixture was stirred for 30 min. The organic phase was separated off and the solvents were removed under reduced pressure. This gave 9.88 g (100%) of colorless crystals which were reacted without further purification.

Quelle