反应详情

To a solution of 2-bromo-3-methyl-5-nitro-benzoic acid methyl ester ((Example 295: step d) 5.04 g) in ethanol (50 mL) was added a solution of aq NaOH (4M, 1.62 g, 40.5 mmol) and stirred at ambient temperature for 16 h. The resulting red colored solution was concentrated to dryness, dissolved in a minimum amount of H2O, and acidified with 1 N HCl to pH 3–4. The solid was filtered, washed with H2O (3×50 mL) dried under high vacuum to afford the title compound (4.5 g, 94% yield) as a pale yellow solid. 1H NMR (DMSO) δ 8.36–8.35 (m, 1H), 8.24–8.23 (m, 1H), 2.53 (s, 3H).

1. concentrationThe resulting red colored solution was concentrated to dryness
2. dissolutiondissolved in a minimum amount of H2O
3. filtrationThe solid was filtered
4. washwashed with H2O (3×50 mL)
5. customdried under high vacuum