A solution of 2,6-difluoro-4-(2-oxoethyl)benzonitrile (185 mg, 1.0 mmol), 1-[2-(4-nitrophenyl)ethyl]piperazine (200 mg, 0.85 mmol) and NaBH(OAc)3 (720 mg, 3.4 mmol) in anhydrous DCM (10 mL) was stirred at ambient temperature overnight. The reaction was completed according to TLC. The reaction mixture was added 20 mL of DCM, washed with brine, separated the organic layer, dried over anhydrous sodium sulfate and concentrated. The residue was purified by preparative TLC to give the product. 1H-NMR (400 MHz, CDCl3) δ ppm 8.15˜8.17 (d, J=8.6 Hz, 2H), 7.37˜7.39 (d, J=8.6 Hz, 2H), 6.92˜6.94 (d, J=8.6 Hz, 2H), 2.50˜3.11 (m, 16H). MS m/z: 401 (M+1)+. (0.16 μM)
