Реакция #706767

Уравнение реакции

6-bromo-2-naphthalenecarboxylic acid

Compound M

6-bromo-2-naphthalenecarboxylic acid

ethanol

sulfuric acid

→

title compound

Ethyl 6-bromo-2-naphthalenecarboxylate

Условия реакции

Обработка

1. 1
   ТемператураThe solution was refluxed for 30 minutes
2. 2
   Другоеthe reaction mixture partitioned between pentane (100 ml) and water (100 ml)
3. 3
   ЭкстракцияThe aqueous phase was extracted with pentane (100 ml)
4. 4
   Промывкаthe combined organic layers washed with saturated aqueous NaCl (100 ml)
5. 5
   Сушкаdried (MgSO4)
6. 6
   Концентрированиеconcentrated
7. 7
   Другоеto yield an off-white solid
8. 8
   ДругоеPurification by flash chromatography (silica, 10% EtOAc-hexane)

Методика

To a solution of 6-bromo-2-naphthalenecarboxylic acid (Compound M) 3.1 g, (12.43 mmol) in ethanol (30 ml, 23.55 g, 511.0 mmol) was added 18M sulfuric acid (2 ml). The solution was refluxed for 30 minutes, cooled to room temperature, and the reaction mixture partitioned between pentane (100 ml) and water (100 ml). The aqueous phase was extracted with pentane (100 ml) and the combined organic layers washed with saturated aqueous NaCl (100 ml), dried (MgSO4), and concentrated to yield an off-white solid. Purification by flash chromatography (silica, 10% EtOAc-hexane) afforded the title compound as a white solid. 1H NMR (CDCl3): δ 8.58 (1H, br s), 8.10 (1H, dd, J=1.7, 9 Hz), 8.06 (1H, d, J=2 Hz), 7.83 (1H, d, J=9 Hz), 7.80 (1H, d, J=9 Hz), 7.62 (1H, dd, J=2, 9 Hz).

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