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

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%).

1. temperaturethe reaction mixture was heated up
2. temperatureto reflux for 4 hours
3. customThe reaction mixture was then carefully quenched into water
4. customthe product was isolated by filtration
5. additionAfter mixing for 1 h
6. customthe reaction was quenched by addition of 6 M HCl to a final pH of 4
7. customThe layers were separated
8. concentrationthe organic layer was concentrated to a slush
9. additionPentane was added
10. customthe product was isolated by filtration
11. customdried

ORD record

ord-6ead266f18104284ab28669989c4738a

Source dataset

uspto-grants-2009_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07538105B2