2) Preparation of 4-chloro-3-iodoaniline (compounds 1-4): a mixture of compounds 1-3 (37 g, 0.13 mol), iron powder (29.3 g, 0.52 mol), and NH4Cl (7 g, 0.13 mol) was dissolved in EtOH/H2O (200 mL/100 mL) and the reaction was stirred for 3 hr at 75 °C. Upon completion of the reaction, the reaction mixture was filtered and concentrated under reduced pressure to remove most of the EtOH. the remaining mixture was extracted with ethyl acetate, washed sequentially with water and saturated saline, and the organic phase was dried with anhydrous Na2SO4. After concentration under reduced pressure, 3-iodo-4-chloroaniline (compounds 1-4) was obtained as a yellow solid (32 g, 97% yield).LCMS: m/z 254.0 [M + 1]+.1H NMR (400 MHz, CDCl3): δ 3.65 (br, 2H), 6.58 (dd, J = 8.8 Hz, 2.4 Hz, 1H), 7.15-7.17 (m, 2H).
