Реакция #7918

Уравнение реакции

BBr3

CH2Cl2

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

→

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

Условия реакции

Обработка

1. 1
   ДругоеThe cooling bath was removed
2. 2
   workup.ADDITIONtreated with more BBr3 in CH2CL2 (0.5 mL, 0.5 mmol)
3. 3
   workup.STIRRINGstirred at room temperature for an additional 60 minutes
4. 4
   workup.ADDITIONThe solution was diluted with EtOAc (10 mL)
5. 5
   Промывкаwashed with water (10 mL), 1N HCl (2 mL), and brine (10 ml)
6. 6
   Сушкаdried over MgSO4
7. 7
   Фильтрацияfiltered
8. 8
   Другоеevaporated under vacuum to an oil
9. 9
   ДругоеThe crude product was purified by preparative layer chromatography on a 0.05×20×20 cm silica gel GF plate

Методика

1M BBr3 in CH2Cl2 (0.200 mL, 0.2 mmol) was added to an ice-cold solution of 4-bromo-7-methoxy-9a-methyl-1,2,9,9a-tetrahydro-3H-fluoren-3-one (10 mg, 0.033 mmol) in CH2CL2 (0.5 mL). The cooling bath was removed and the solution was stirred at room temperature for 30 minutes, then treated with more BBr3 in CH2CL2 (0.5 mL, 0.5 mmol) and stirred at room temperature for an additional 60 minutes. The solution was diluted with EtOAc (10 mL), washed with water (10 mL), 1N HCl (2 mL), and brine (10 ml), dried over MgSO4, filtered, and evaporated under vacuum to an oil. The crude product was purified by preparative layer chromatography on a 0.05×20×20 cm silica gel GF plate, developing with 5% CH3OH in CH2Cl2, to afford 4-bromo-7-hydroxy-9a-methyl-1,2,9,9a-tetrahydro-3H-fluoren-3-one as a gum.

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