Acetic Acid → ethyl 8-chloro-1-cyclopropyl-9-difloromethoxy-4-oxo-4H-quinolizine-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

71.6 mg of 2-(4-chloro-3-difluoromethyl-2-pyridyl)-2-cyclopropylethanal (XII) was dissolved in 3 ml of anhydrous ethanol, to which were added 80 μl of piperidine, 80 μl of acetic acid and 220 μl of diethyl malonate and the resulting mixture was heated at 100° C. for 5 hours. The solvent was distilled off by under reduced pressure, and thereafter, the resulting mixture was diluted with ether, and the resulting organic layer was washed with water and saturated salt water, and dried over anhydrous sodium sulfate, and the solvent was distilled off by under reduced pressure. 2 ml of Dowtherm A was added to the resulting residue, and the resulting mixture was heated at 240° C. for 30 minutes. The reaction solution was purified directly by silica gel column chromatography (eluent; hexane→hexane:ethyl acetate=1:1) to obtain 51.3 mg of ethyl 8-chloro-1-cyclopropyl-9-difluoromethyl-4-oxo-4H-quinolidine-3-carboxylate (XIII).

Provenance & Evidence