Реакция #167032

Уравнение реакции

3,8-dibromo-benzo[c]chromen-6-one

LiBH4

→

3,8-Dibromo-6H-benzo[c]chromene

Выход 86.0%

Растворители

THF

THF

Условия реакции

Обработка

1. 1
   ДругоеQuenched slowly with ammonium chloride solution
2. 2
   ЭкстракцияThe mixture was extracted with ethyl acetate
3. 3
   Сушкаdried over Na2SO4
4. 4
   Фильтрацияfiltered
5. 5
   Концентрированиеconcentrated in vacuo
6. 6
   Температураheated at 160° C. for 4 h
7. 7
   ЭкстракцияThe mixture was extracted with ethyl acetate
8. 8
   Промывкаwashed with water
9. 9
   Сушкаdried over Na2SO4
10. 10
    Фильтрацияfiltered
11. 11
    Концентрированиеconcentrated in vacuo
12. 12
    ДругоеThe obtained residue was purified by flash chromatography

Методика

To a solution of 3,8-dibromo-benzo[c]chromen-6-one (650 mg, 1.85 mmol) in THF (20 mL) was added 2 M solution of LiBH4 in THF (3.7 mL, 7.4 mmol). The mixture was stirred for 3 hours at room temperature. Quenched slowly with ammonium chloride solution. The mixture was extracted with ethyl acetate, dried over Na2SO4, filtered and concentrated in vacuo. The obtained residue was suspended in 85% phosphoric acid (20 mL) and heated at 160° C. for 4 h. The mixture was extracted with ethyl acetate, washed with water, dried over Na2SO4, filtered and concentrated in vacuo. The obtained residue was purified by flash chromatography to provide the desired product 3,8-Dibromo-6H-benzo[c]chromene as a white solid (539 mg, 86%).

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