2-Chloro-5-nitrobenzenesulfonic acid → 2-Chloro-5-nitrobenzenesulfonamide

Participants

Reaction Steps

To a solution of thionyl chloride (240 mL) and 2-chloro-5-nitro-benzenesulfonic acid (104 g, 437.6 mmol) was added N,N-dimethylformamide (2 mL) and the reaction mixture was heated up to reflux for 4 hours. The reaction mixture was then carefully quenched into water and the product was isolated by filtration. The sulfonyl chloride 2 was then dissolved in toluene and added to a mixture of NH4OH (520 mL) and tetrahydrofuran (520 mL) at −10° C. After mixing for 1 h, the reaction was quenched by addition of 6 M HCl to a final pH of 4. The layers were separated and the organic layer was concentrated to a slush. Pentane was added and the product was isolated by filtration and dried to give the title compound (82.6 g, 80%).

Provenance & Evidence