Potassium Iodide → 4-Fluoro-2-iodo-1-nitrobenzene

To a solution of 5-fluoro-2-nitroaniline (70.0 g, 448 mmol) in HCl (350 mL, 37% in water) at 0° C. was added sodium nitrite (32.2 g, 469 mmol, in 100 mL water) dropwise. The mixture was stirred for 1 h at which time, potassium iodide (82.0 g, 490 mmol, in 100 mL H2O) was added dropwise. The mixture was stirred at rt for 2 h and then extracted with EtOAc. The organic layer was washed with brine, dried (MgSO4) and purified by flash chromatography to provide the title compound (98.6 g, 368 mmol, 83%). 1H NMR (400 MHz, CDCl3) δ ppm 7.15-7.23 (m, 1H), 7.75 (dd, J=3.50 Hz, J=7.60 Hz, 1H), 7.97 (dd, J=1.6 Hz, J=8.8 Hz, 1H).