Thionyl Chloride → 5-(Aminosulphonyl)-2-methoxybenzoyl chloride
Reaction equation
[CH3:1][O:2][C:3]1[CH:11]=[CH:10][C:9]([S:12](=[O:15])(=[O:14])[NH2:13])=[CH:8][C:4]=1[C:5](O)=[O:6].S(Cl)([Cl:18])=O>O1CCCC1>[CH3:1][O:2][C:3]1[CH:11]=[CH:10][C:9]([S:12](=[O:15])(=[O:14])[NH2:13])=[CH:8][C:4]=1[C:5]([Cl:18])=[O:6]Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
To a suspension of the so-obtained 2-methoxy-5-sulfamoyl benzoic acid in 600 parts of anhydrous tetrahydrofuran, there were added rapidly 27.5 parts of thionyl chloride. The mixture was refluxed for 2 hours. The solution was then evaporated under vacuo. The residue was treated with 500 parts of anhydrous benzene. After elimination of benzene in vacuo, there were obtained 29 parts of 2-methoxy-5-sulfamoyl benzoyl chloride, M.P. 148°-150° C, which after one recrystallization from benzene melts at 156° C.