Reaction #45554

Reaction equation

water

dichloromethane

N-(3′-benzyloxy-2-bromo-5-cyano-3-methoxy-6-methylbiphenyl-4-yl)-2,2-dimethylpropionamide

dichloromethane

tribromoborane

→

compound

Yield 96.0%

N-(2-Bromo-5-cyano-3,3′-dihydroxy-6-methylbiphenyl-4-yl)-2,2-dimethylpropionamide

Yield 96.0%

Solvents

brine

Conditions

Workup

1. 1
   TemperatureAfterwards, this was heated up to −12° C.
2. 2
   workup.STIRRINGstirred for 1 hour
3. 3
   Temperatureheated up to 0° C.
4. 4
   workup.STIRRINGstirred for 30 minutes
5. 5
   OtherThe reaction liquid
6. 6
   workup.ADDITIONwas added
7. 7
   Extractionthe intended product was extracted with ethyl acetate (70 ml×2)
8. 8
   DryingThe organic layer was dried over anhydrous magnesium sulfate
9. 9
   Concentrationconcentrated under reduced pressure
10. 10
    Otherthe residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=3:1)

Procedure

A dichloromethane (18 ml) solution of N-(3′-benzyloxy-2-bromo-5-cyano-3-methoxy-6-methylbiphenyl-4-yl)-2,2-dimethylpropionamide (I-13) (620 mg, 1.22 mmol) was cooled at −78° C., a dichloromethane solution of 1 N tribromoborane (3.67 ml, 3.67 mmol) was dropwise added, followed by stirring at −78° C. for 20 minutes. Afterwards, this was heated up to −12° C. and stirred for 1 hour, then heated up to 0° C. and stirred for 30 minutes. The reaction liquid was put into cold water (50 ml), saturated brine (50 ml) was added, the intended product was extracted with ethyl acetate (70 ml×2). The organic layer was dried over anhydrous magnesium sulfate, concentrated under reduced pressure, the residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=3:1) to obtain the entitled compound (457 mg, 96%) as a yellow white semi-solid.

Source