Sodium hydride → Ethyl 5-phenyl-1-(2-thienylsulfonyl)-1H-pyrrole-3-carboxylate

To a solution (20 mL) of ethyl 5-phenyl-1H-pyrrole-3-carboxylate (440 mg) in tetrahydrofuran was added sodium hydride (60% in oil, 123 mg) at room temperature and the mixture was stirred for 30 min. 15-Crown-5 (675 mg) was added dropwise and the mixture was stirred for 30 min. 2-Thiophenesulfonyl chloride (485 mg) was added, and the mixture was further stirred for 1 hr. Saturated brine was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: hexane-ethyl acetate=19:1→7:3), and crystallized from diisopropyl ether.hexane to give the title compound as colorless crystals (yield 710 mg, 96%).

1. stirringthe mixture was stirred for 30 min
2. stirringthe mixture was further stirred for 1 hr
3. extractionthe mixture was extracted with ethyl acetate
4. washThe extract was washed with saturated brine
5. dry with materialdried over anhydrous magnesium sulfate
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by silica gel column chromatography (eluent: hexane-ethyl acetate=19:1→7:3)
8. customcrystallized from diisopropyl ether

ORD record

ord-2f250cc0c3f2415aaa5d9d793d2bd6a6

Source dataset

uspto-grants-2011_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08048909B2