Reaction #50106

Reaction equation

water

BBr3

epoxide

1,3-dichloro-3-fluoro-7-oxabicyclo[4.1.0]heptane

→

alcohol

2-bromo-2,6-dichloro-6-fluorocyclohexanol

Solvents

dichloromethane

dichloromethane

Conditions

Workup

1. 1
   Otherto return to room temperature
2. 2
   Other(1 h 30 min)
3. 3
   Extractionthe mixture was extracted with dichloromethane (4×10 cm3)
4. 4
   DryingThe extract was dried over MgSO4
5. 5
   Filtrationfiltered
6. 6
   Otherevaporated down
7. 7
   OtherThe crude product was purified by flash chromatography on silica (eluent ether/petroleum ether=5/95)

Procedure

2.91 cm3 (2.91 mmol) of BBr3 in molar solution in dichloromethane were introduced at 4° C. under argon atmosphere into 0.98 (5.3 mmol) of epoxide 2e in solution in 6.5 cm3 dichloromethane. The reaction mixture was then allowed to return to room temperature and stirring was continued (1 h 30 min). 5 cm3 of distilled water were then added and the mixture was extracted with dichloromethane (4×10 cm3). The extract was dried over MgSO4, filtered and evaporated down. The crude product was purified by flash chromatography on silica (eluent ether/petroleum ether=5/95): 1.03 g of alcohol 1i were obtained (macrobore GC purity>97%); the yield of product 1i was 73%.

Source