2-Methoxyaniline → 4-Bromo-2-methoxyaniline

Beteiligte Stoffe

Reaktionsschritte

A solution of o-Anisidine (5.46 g, 44.3 mmol) in dichloromethane (100 mL) was treated with 2,4,4,6-tetrabromo-2,5-cyclohexadiene-1-one (18.16 g, 44.3 mmol) portion-wise over 1 h at −5° C. Following the addition of the brominating agent, the dry ice/acetone bath was removed and the reaction mixture stirred over night at room temperature. Sodium hydroxide solution (1N) was added to the reaction mixture, and the layers were partitioned. The organic layer was washed with 1 N sodium hydroxide solution (1 L), washed with water (750 mL), dried over magnesium sulfate, filtered, and evaporated under reduced pressure, to give 8.096 g (89%) of 4-bromo-2-methoxyaniline. 1H NMR (DMSO-d6, 400 MHz) δ 6.90 (s, 1H), 6.83-6.76 (m, 1H), 6.57-6.55 (m, 1H), 4.86 (s, 2H), 3.76 (s, 3H); HPLC Waters 2690 Alliance HPLC (Symmetry Shield RP18 3.5 μm, 2.1×50 mm; 5%-95% acetonitrile-0.1 M ammonium acetate over 15 min, 0.5 mL/min) Rt 5.635 min (89%).

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