Reaction #1810820

Reaction equation

HCl

sodium sulfite

2-chloro-5-fluorosulfonyl-benzoic acid

NaOH

→

title compound

Yield 76.5%

2-Chloro-5-sulfino-benzoic acid

Yield 76.5%

Solvents

water

water

Conditions

Workup

1. 1
   Otherwas removed under vacuum
2. 2
   workup.ADDITIONMethanol was added
3. 3
   Filtrationthe precipitate filtered off
4. 4
   Concentrationthe filtrate concentrated
5. 5
   workup.ADDITIONMethanol and diethylether were added
6. 6
   Filtrationthe precipitate was filtered off
7. 7
   Washwashed with ether
8. 8
   Otherdried

Procedure

A solution of 33.59 g (267 mmol) sodium sulfite in 100 ml water at 0° C. is treated with 21.2 g (89 mmol) 2-chloro-5-fluorosulfonyl-benzoic acid and 26.6 ml of a 10 M aqueous NaOH solution (267 mmol). The mixture was allowed to stir for 3 h at room temperature, acidified with HCl conc. (pH=4) and water was removed under vacuum. Methanol was added, the precipitate filtered off and the filtrate concentrated. Methanol and diethylether were added and the precipitate was filtered off washed with ether and dried to yield 15 g (76.5%) of the title compound as white gum. MS (m/e): 219.1 (M−H, 100%)

Source