Реакция #7917

Уравнение реакции

7-methoxy-9a-methyl-1,2,9,9a-tetrahydro-3H-fluoren-3-one

NaHCO3

bromine

→

4-bromo-7-methoxy-9a-methyl-1,2,9,9a-tetrahydro-3H-fluoren-3-one

Выход 46.5%

Растворители

CH2Cl2

EtOAc

Условия реакции

Обработка

1. 1
   Промывкаwashed with dilute aqueous Na2S2O3 (4 mL) and brine (4 ml)
2. 2
   Сушкаdried over MgSO4
3. 3
   Фильтрацияfiltered
4. 4
   Другоеevaporated under vacuum to a yellow oil (43 mg)
5. 5
   ДругоеThis material was purified by preparative layer chromatography on a 0.05×20×20 cm silica gel GF plate

Методика

A mixture of 7-methoxy-9a-methyl-1,2,9,9a-tetrahydro-3H-fluoren-3-one (32 mg, 0.14 mmol) and NaHCO3 (60 mg, 0.7 mmol) in CH2Cl2 (0.5 ml) was treated with bromine (0.008 mL, 0.154 mmol), and the resulting mixture was stirred at room temperature for 22 hours. The mixture was diluted with EtOAc (8 ml), washed with dilute aqueous Na2S2O3 (4 mL) and brine (4 ml), dried over MgSO4, filtered, and evaporated under vacuum to a yellow oil (43 mg). This material was purified by preparative layer chromatography on a 0.05×20×20 cm silica gel GF plate, developing twice with CH2Cl2, to afford 4-bromo-7-methoxy-9a-methyl-1,2,9,9a-tetrahydro-3H-fluoren-3-one (20 mg) as a gum. The product was contaminated with a trace of 4,6-dibromo-7-methoxy-9a-methyl-1,2,9,9a-tetrahydro-3H-fluoren-3-one.

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