Nitric Acid → 2-Nitro-4-((trifluoromethyl)thio)phenol

To a mixture of 4.8 g of 4-(trifluoromethylthio)phenol and 20 ml of acetic acid, a mixture of 2.5 g of 70% nitric acid and 1 ml of acetic acid and then 1.5 ml of concentrated sulfuric acid were added dropwise with the internal temperature kept at 10-15° C. The reaction mixture was stirred for three hours. The reaction mixture was poured into ice water and extracted with ethyl acetate. The combined organic layers were washed with water, a saturated aqueous solution of sodium hydrogencarbonate and a saturated sodium chloride solution, dried over magnesium sulfate, and then concentrated under reduced pressure to give 5.94 g of 2-nitro-4-(trifluoromethylthio)phenol.