GENERAL METHOD: Suspend NaH (75 mmol) in DMF (60 mL) at 0°C and slowly add 4-chloroaniline (50 mmol). After stirring for 30 min at 0°C, a solution of 1-fluoro-2-nitrobenzene (60 mmol) in DMF (30 mL) was added dropwise. The reaction mixture was gradually warmed to room temperature and stirred continuously for 16 hours. Upon completion of the reaction, the mixture was carefully poured into a stirred saturated NH4Cl solution (500 mL) and the precipitate was collected by filtration. The filter cake was washed with water and purified by recrystallization from methanol to give the target product N-(4-chlorophenyl)-2-nitroaniline (15h). The product was an orange solid with a yield of 72.3% and a melting point of 135.1-137.0 °C. 1H NMR (400 MHz, DMSO-d6) δ 9.31 (s, 1H), 8.12 (d, J = 8.0 Hz, 1H), 7.53 (t, J = 7.6 Hz, 1H), 7.44 (d, J = 8.8 Hz, 2H), 7.34 (d, J = 8.8 Hz, 2H), 7.22 (d, J = 8.4 Hz, 1H), 6.93 (t, J = 7.6 Hz, 1H).MS (ESI) m/z (%): 247.2 [M-H]-.
