A suspension of 26.4 g of ethyl 2,3,4,5-tetrafluorobenzoylacetate, 18.7 g of 2-(dimethylaminomethyl)morpholine and 8.4 g sodium hydrogencarbonate in 130 ml of acetonitrile is refluxed for 7 hours. The reaction mixture is concentrated under reduced pressure, to the obtained residue is added 100 ml of chloroform and the solution is washed with water. After drying over anhydrous magnesium sulfate, the chloroform is distilled off under reduced pressure and the residue is purified by chromatography on silica gel to give 29.9 g of ethyl 4-[2-(dimethylaminomethyl)morpholino]-2,3,5-trifluorobenzoylacetate in 77% yield as an oily substance.
