Diethyl Malonate → Ethyl 2,4,5-trifluorobenzoylacetate

On the other hand, a suspension of magnesium ethoxide and 3.1 g of diethyl malonate in 30 ml of anhydrous diethyl ether was refluxed for 1 hour. To the cooled suspension was added dropwise 15 ml of an anhydrous diethyl ether solution of 2,4,5-trifluorobenzoyl chloride obtained above with stirring. The resulting mixture was stirred at room temperature for 1 hour. After acidification with diluted hydrochloric acid, the mixture was extracted with 150 ml of ethyl acetate (50 ml×3). The extract was dried over sodium sulfate, and the solvent was removed by distillation. The resulting residue was dissolved in 50 ml of dioxane and a catalytic amount of p-toluenesulfonic acid was added thereto. The mixture was refluxed for 24 hours and, after cooling, the reaction mixture was neutralized with an aqueous sodium bicarbonate solution and extracted with 200 ml of chloroform. The extract was dried over sodium sulfate, and the solvent was removed. The residue was subjected to silica gel column chromatography and 2.1 g of ethyl 2,4,5-trifluorobenzoylacetate was yielded from benzene eluate.

1. temperaturewas refluxed for 1 hour
2. customobtained above
3. stirringThe resulting mixture was stirred at room temperature for 1 hour
4. extractionAfter acidification with diluted hydrochloric acid, the mixture was extracted with 150 ml of ethyl acetate (50 ml×3)
5. dry with materialThe extract was dried over sodium sulfate
6. customthe solvent was removed by distillation
7. dissolutionThe resulting residue was dissolved in 50 ml of dioxane
8. additiona catalytic amount of p-toluenesulfonic acid was added
9. temperatureThe mixture was refluxed for 24 hours
10. temperatureafter cooling
11. extractionextracted with 200 ml of chloroform
12. dry with materialThe extract was dried over sodium sulfate
13. customthe solvent was removed

ORD record

ord-96e4697eafcb443a9a4081df890b79f3

Source dataset

uspto-grants-1989_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04871852