Azobisisobutyronitrile → Ethyl 4-(bromomethyl)-5-(4-chlorophenyl)-3-(4-sulfamoylphenyl)thiophene-2-carboxylate

Temperature

85 °C

To a stirred solution of Ethyl 5-(4-chlorophenyl)-4-methyl-3-(4-sulfamoylphenyl)thiophene-2-carboxylate (Compound 1b, 4.0 g, 9.17 mmol) in chlorobenzene (50 ml) were added NBS (1.77 g, 10.09 mmol) and AIBN (1.65 g, 10.09 mmol) at 25° C. The reaction mixture was then stirred at 85° C. for 4 hr. The progress of the reaction was monitored by TLC. The reaction mixture was then cooled to room temperature and was quenched in aqueous sodium chloride solution (50 ml). The mixture so obtained was then extracted with Ethyl acetate (2×50 ml). The organic layer was washed with brine (1×50 ml) and dried over sodium sulfate and concentrated under reduced pressure to obtain crude product (4.0 g). The crude product was then purified by column chromatography over silica gel (100-200 mesh) using 40% ethyl acetate in hexanes as an eluent to obtain the title compound (2.8 g, 59.32%).

1. temperatureThe reaction mixture was then cooled to room temperature
2. customwas quenched in aqueous sodium chloride solution (50 ml)
3. customThe mixture so obtained
4. extractionwas then extracted with Ethyl acetate (2×50 ml)
5. washThe organic layer was washed with brine (1×50 ml)
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated under reduced pressure
8. customto obtain crude product (4.0 g)
9. customThe crude product was then purified by column chromatography over silica gel (100-200 mesh)

ORD record

ord-393e630eb28f46b49cdb6c004e7890eb

Source dataset

uspto-grants-2015_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09072731B2