Reaktion #1168586

Reaktionsgleichung

n-butyllithium

hydrochloric acid

2,4,5-trifluoro-6-methylbenzoyl chloride

malonic acid monoethylester

bipyridyl

n-butyllithium

→

title compound

Ausbeute 82.7%

Ethyl 3-(2,4,5-trifluoro-6-methylbenzoyl)-β-oxopropanoate

Ausbeute 82.7%

Lösungsmittel

THF

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was cooled to -78° C
2. 2
   TemperaturThe solution was then warmed to -35° C.
3. 3
   Extraktionextracted with ethyl acetate
4. 4
   WaschenThe organic layer was washed with 5% sodium bicarbonate, 3M hydrochloric acid, and water
5. 5
   workup.STIRRINGwas stirred over magnesium sulfate
6. 6
   EinengenConcentration
7. 7
   Sonstigegave an orange oil which
8. 8
   Sonstigewas chromatographed on silica gel (E. Merck 230-400 Mesh)
9. 9
   Wascheneluting with 80:20 chloroform

Vorschrift

A solution of 8.0 g (60.5 mmol) of malonic acid monoethylester, bipyridyl (catalytic) and 200 mL of dry THF was cooled to -35° C. under argon, treated with 32 mL of 1.9M n-butyllithium (60.8 mmol), and warmed to -5° C. To this suspension was added another 32 mL of 1.9M n-butyllithium until a pale pink color persisted for 10 minutes. The mixture was cooled to -78° C. To this mixture was added a solution of 6.3 g (30.2 mmol) of 2,4,5-trifluoro-6-methylbenzoyl chloride in 75 mL of dry THF, and the reaction mixture was stirred at -78° C. for 1 hour. The solution was then warmed to -35° C., poured onto a mixture of ice and 1N hydrochloric acid (70 mL), and extracted with ethyl acetate. The organic layer was washed with 5% sodium bicarbonate, 3M hydrochloric acid, and water, and was stirred over magnesium sulfate. Concentration gave an orange oil which was chromatographed on silica gel (E. Merck 230-400 Mesh), eluting with 80:20 chloroform:ethyl acetate, to give 7.2 g of the title compound.

Quelle