Sulfur Dioxide → HCID 86630944, compound

Temperature

-75 °C

To a solution of 2,7-dibromo-6-methoxy-benzo[b]thiophene (1.1 g, 3.4 mmol) in diethyl ether (40 mL) was added dropwise at −75° C. n-BuLi (1.6N, 2.35 mL, 3.75 mmol). The reaction mixture was stirred at −75° C. for 1 h, then a stream of sulfur dioxide was passed over the surface of the solvent until the reaction was no more exothermic. The suspension was then stirred at rt for 1 h and concentrated under vacuum. The residue was quenched with sat. sodium bicarbonate-solution (30 mL), and at 0-5° C. N-chlorosuccinimide (0.525 g, 3.95 mmol) was added. The mixture was stirred at rt for 1 h, quenched with water, and extracted with ethyl acetate. The organic phases were dried and concentrated. The residue was chromatographed on silica gel using heptane/ethyl acetate as eluent to obtain 7-bromo-6-methoxy-benzo[b]thiophene-2-sulfonyl chloride (0.57 g). MS (EI) m/e 339.9 (M)

1. stirringThe suspension was then stirred at rt for 1 h
2. concentrationconcentrated under vacuum
3. customThe residue was quenched with sat. sodium bicarbonate-solution (30 mL)
4. customat 0-5° C
5. stirringThe mixture was stirred at rt for 1 h
6. customquenched with water
7. extractionextracted with ethyl acetate
8. customThe organic phases were dried
9. concentrationconcentrated
10. customThe residue was chromatographed on silica gel

ORD record

ord-09ce475f38954d7e9231bef47e1203bb

Source dataset

uspto-grants-2011_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07973051B2