Water → Ethyl 2-methyl-4,4,4-trifluoroacetoacetate

Beteiligte Stoffe

Reaktionsschritte

Sodium hydride (7.05 g of a 50% oil dispersion, 0.15 mol) was washed 3 times with 25 ml of dimethoxyethane to remove the oil and then suspended in 220 ml of dimethoxyethane, under an argon atmosphere and cooled in an ice bath. A solution of ethyl 3-keto-4,4,4-trifluorobutanoate (25.77 g, 0.14 mol) in 25 ml of dimethoxyethane was added dropwise from an addition funnel to the stirred suspension. After the addition was completed, the cooling bath was removed and the reaction mixture stirred for 30 minutes past the cessation of hydrogen gas evolution. Methyl iodide (43.0 ml, 0.70 mole) was added by syringe and the reaction mixture refluxed overnight. The reaction was cooled to room temperature and poured into a separatory funnel containing a 1:1:1 mixture of saturated ammonium chloride:brine:water. The layers were separated and the aqueous phase extracted with 100 ml ether. The combined organic phase and ether extract was washed with brine, dried over magnesium sulfate and filtered. The solvents were removed by distillation at atmospheric pressure using a Vigreaux column leaving ethyl 3-keto-2-methyl-4,4,4-trifluorobutanoate as the pot residue. Rf: (EtAc/hexane--20:80)

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