Reaction #7834

Reaction equation

3-chloro-4-methylbenzoic acid

N-bromosuccinimide

benzoyl peroxide

→

4-(bromomethyl)-3-chlorobenzoic acid

Solvents

CCl4

Conditions

Workup

1. 1
   Temperatureat reflux for 2.5 h
2. 2
   ConcentrationThe mixture was concentrated under reduced pressure
3. 3
   workup.DISSOLUTIONdissolved in MTBE
4. 4
   WashThe organic mixture was washed with 1N NaOH (3×25 mL)
5. 5
   Extractionextracted with CH2Cl2 (3×25 mL)
6. 6
   DryingThe combined organic layers were dried over MgSO4
7. 7
   Filtrationfiltered
8. 8
   Concentrationconcentrated

Procedure

A solution of 3-chloro-4-methylbenzoic acid (5.0 g, 29 mmol), N-bromosuccinimide (5.7 g, 32 mmol), benzoyl peroxide (710 mg, 2.9 mmol) in CCl4 (300 mL) was heated at reflux for 2.5 h. The mixture was concentrated under reduced pressure and dissolved in MTBE. The organic mixture was washed with 1N NaOH (3×25 mL). The aqueous mixture was acidified with 1N HCl to pH 2 and extracted with CH2Cl2 (3×25 mL). The combined organic layers were dried over MgSO4, filtered and concentrated to afford 4-(bromomethyl)-3-chlorobenzoic acid.

Source