Reaction #1458451

Reaction equation

2-(4-nitrophenyl)ethanol

diethylaminosulfur trifluoride

sodium hydrogen carbonate

→

1-fluoro-2-(4-nitrophenyl)ethane

Solvents

methylene chloride

methylene chloride

Conditions

Workup

1. 1
   Otherto rise back to room temperature
2. 2
   WashThe methylene chloride solution was washed with saturated aqueous sodium hydrogen carbonate solution (50 mL)
3. 3
   DryingAfter drying over anhydrous magnesium sulfate
4. 4
   Otherthe solvent was evaporated under reduced pressure
5. 5
   OtherThe residue was purified by chromatography on a silica gel (25 g) column

Procedure

A solution of 2-(4-nitrophenyl)ethanol (835 mg) in methylene chloride (30 mL) was stirred at −78° C. under a nitrogen atomosphere. To this solution, diethylaminosulfur trifluoride (1.98 mL) in methylene chloride (20 mL) was added dropwise over 10 minutes. With stirring, the temperature of the reaction mixture was allowed to rise back to room temperature. After 30 minutes, the reaction was stopped by the addition of saturated aqueous sodium hydrogen carbonate solution (50 mL) in an ice bath. The methylene chloride solution was washed with saturated aqueous sodium hydrogen carbonate solution (50 mL). After drying over anhydrous magnesium sulfate, the solvent was evaporated under reduced pressure. The residue was purified by chromatography on a silica gel (25 g) column using hexane:ethyl acetate (7:2) as the eluant to give 1-fluoro-2-(4-nitrophenyl)ethane (359 mg).

Source