Hydrochloric Acid → Ethyl 6-methyl-2,3,4,5-tetrafluorobenzoylacetate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of 10.1 g (76.5 mmol) of malonic acid monoethylester, bipyridyl (catalytic), and 200 ml of dry THF was cooled to -35° C. under argon, treated with 52 ml of 1.5M n-butyllithium (78 mmol), and warmed to -5° C. To this mixture was added 52 ml of 1.5M n-butyllithium (78 mmol) until a pale pink color persisted for 10 minutes. The suspension was cooled to -78° C. and was treated with a solution of 8.8 g (38.8 mmol) of 2,3,4,5-tetrafluoro-6-methylbenzoyl chloride in 100 ml of dry THF. The reaction mixture was stirred at -78° C. for 45 minutes, then warmed to -35° C. and poured into a mixture of ice and 1N hydrochloric acid (77 ml). The organic layer was washed with 5% sodium bicarbonate solution, 3M hydrochloric acid, and water and dried 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 8.2 g of the title compound.

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