Iodoethane → 3-Bromo-2-chloro-5-(ethylsulfonyl)pyridine

Temperature

75 °C

Sodium sulfite (4.94 g, 39.2 mmol) and sodium bicarbonate (3.46 g, 41.2 mmol) in water (100 mL) were heated to 75° C. 3-bromo-2-chloropyridine-5-sulfonyl chloride (6.00 g, 20.6 mmol) was added portionwise over 1 hour. The reaction mixture was stirred at 75° C. for 1 hour after complete addition. The mixture was concentrated under vacuum. N,N-Dimethylformamide (37.5 mL), sodium bicarbonate (3.46 g, 41.2 mmol) and iodoethane (1.658 mL, 20.62 mmol) were added. The resulting mixture was heated to 75° C. for 2 hours then cooled to room temperature. The mixture was partitioned between ethyl acetate and water. The organic layer was washed with saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate, filtered, and concentrated. The reaction mixture was purified by flash chromatography (silica gel, 100% heptane to 100% ethyl acetate) to provide the title compound (3.15 g, 53% yield).

1. additionafter complete addition
2. concentrationThe mixture was concentrated under vacuum
3. temperatureThe resulting mixture was heated to 75° C. for 2 hours
4. temperaturethen cooled to room temperature
5. customThe mixture was partitioned between ethyl acetate and water
6. washThe organic layer was washed with saturated aqueous sodium chloride
7. dry with materialdried over anhydrous magnesium sulfate
8. filtrationfiltered
9. concentrationconcentrated
10. customThe reaction mixture was purified by flash chromatography (silica gel, 100% heptane to 100% ethyl acetate)

ORD record

ord-f7fb6e2e606b416c8e83f761f428c6e8

Source dataset

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09321764B2