Sulfuric Acid → HCID 14099128, compound

Participants

Reaction Steps

A mixture of 4.0 g (0.021 mole) of the 3,4-difluoro-N-ethyl-2-methoxyaniline (XIII) [prepared as described in Step (C3) above] and 5.54 g (0.026 mole) of diethyl ethoxymethylenemalonate was heated at 150°-160° C. for 9 hours. The mixture was then allowed to cool to room temperature, and 42 ml of acetic anhydride and 18 ml of concentrated sulfuric acid were then added, in that order. The reaction mixture was poured into ice-water to precipitate crystals, which were collected by filtration to give 2.09 g of ethyl 6,7-difluoro-1-ethyl-8-methoxy-1,4-dihydro-4-oxoquinoline-3-carboxylate (X, R9' =ethyl) as a colorless powder.

Provenance & Evidence