A mixture of 2-chloro-4-methylsulfonyl-1- nitro-benzene (4.5 g, 19.10 mmol, 1 eq.) in EtOH (40 mL) and a saturated NH4Cl solution (10 mL) was heated to 90 °C, and then Fe (3.20 g, 57.29 mmol, 3 eq.) was added in one portion. The reaction mixture was stirred at 90 °C for 1 h, after which time TLC analysis (PE:EtOAc = 1:1, Rf(starting material) = 0.7, Rf(product) = 0.31) indicated that the reaction was complete. The reaction was diluted with water (50 mL) and extracted with EtOAc (100 mL x 3). The combined organic layers were washed with water (50 mL x 3) and brine (50 mL x 2), dried over anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The residue was purified by column chromatography (SiO2, PE:EtOAc = 4:1 to 2:1) to provide 2-chloro-4-methylsulfonyl-aniline (3.7 g, 17.99 mmol, 94.21% yield) as an off-white solid.
