2-amino-4-bromo-5-methylphenol

182500-28-3

848358-81-6

General procedure for the synthesis of 4-bromo-5-methyl-2-nitrophenol from 4-bromo-5-methyl-2-nitrophenol: To a stirred solution of 4-bromo-5-methyl-2-nitrophenol (1.8 g, 7.76 mmol) in methanol (20 mL) was added sequentially stannous chloride (II) dihydrate (5.88 g, 31.0 mmol) and concentrated hydrochloric acid (1.65 mL , 54.3 mmol) and the reaction was carried out at room temperature. The reaction mixture was heated to 75 °C and maintained for 2 hours. After completion of the reaction, the mixture was cooled to room temperature and concentrated under reduced pressure to remove the solvent. The crude product was dissolved with ethyl acetate (100 mL), the pH was adjusted to 14 with ammonia and the solid suspension formed was filtered through a bed of diatomaceous earth. The filtrate was washed with ethyl acetate (2 x 50 mL). The combined organic phases were washed sequentially with water (50 mL) and saturated saline (50 mL), dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated under reduced pressure to afford 1.3 g (83% yield) of the target product 4-bromo-5-methyl-2-aminophenol as a white solid. The product was characterized by 1HNMR (400 MHz, CDCl3) and GC-MS: 1HNMR δ 6.96 (s, 1H), 6.64 (s, 1H), 3.61 (bs, 2H, D2O exchangeable), 2.26 (s, 3H); GC-MS (m/z) 201,203 [M+, Br79,81].