Sodium hydride → Ethyl 1-cyclopropyl-6,7,8-trifluoro-5-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylate

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Reaction Steps

Ethyl 2-(6-methyl-2,3,4,5-tetrafluorobenzoyl)-3-cyclopropylaminoacrylate (4.50 g) is dissolved in anhydrous dioxane (26 ml) and thereto 60% sodium hydride (580 mg) is gradully added under ice-cooling. After stirring at room temperature for 30 minutes, the reaction mixture is poured into ice-water and extracted with dichloromethane. The extract is dried over magnesium sulfate and concentrated. The residue is added with diethyl ether and crystals are filtered, which are recrystalized from dichloromethane--n -hexane to give ethyl 1-cyclopropyl-6,7,8-trifluoro-5-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylate (4.19 g), as white needles, m.p. 180°-183° C.

Provenance & Evidence