Methanol → Methyl 4-bromo-2-(methylsulfonyl)benzoate
Reaction equation
[Br:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([OH:8])=[O:7])=[C:4]([S:11]([CH3:14])(=[O:13])=[O:12])[CH:3]=1.S(=O)(=O)(O)O.[CH3:20]O>>[Br:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([O:8][CH3:20])=[O:7])=[C:4]([S:11]([CH3:14])(=[O:13])=[O:12])[CH:3]=1Participants
4
Procedure
A suspension of 4-bromo-2-(methylsulphonyl)benzoic acid (5.00 g; 17.9 mmol) in MeOH (100 ml) was treated with conc. sulphuric acid and the resulting mixture was heated at reflux for 5 days. The mixture was concentrated under reduced pressure, the residue was dissolved in EtOAc then washed with water, twice with NaHCO3 (sat) then with brine, dried on MgSO4, filtered and concentrated to give the title compound as a yellow solid (4.00 g, 72%).