(E)-4,4,4-Trifluorobut-2-enoic acid (15.4 mg, 0.08 mmol) was dissolved in DCM (1 ml), oxalyl chloride was added (9.4 μl, 0.11 mmol) followed by a drop of DMF. The mixture was stirred for 10 minutes at room temperature. Methyl 2-[1-(2-methyl-4-quinolyl)piperazin-2-yl]acetate (33.6 mg, 0.1 mmol) was dissolved in DMF (1 ml) together with diisopropylethylamine (44 μl, 0.25 mmol), the solutions were combined and the resulting mixture was stirred at room temperature overnight. The volatiles were removed under reduced pressure and the residue was purified by preparative HPLC (gradient of water containing 0.1% NH3 and acetonitrile) to yield 3.9 mg (0.0093 mmol, 9%).
