2-Chloro-3-nitropyridine → 7-Chloro-1H-pyrrolo[2,3-c]pyridine

A solution of 2-chloro-3-nitropyridine (1 g, 6.3 mmol) in dry tetrahydrofuran (100 mL) was treated with vinyl magnesium bromide (60 mL, 60 mmol) at −78° C. in a drop-wise manner under inert atmosphere. The resulting reaction mixture was stirred at the same temperature for 2 hours followed by stirring at −20° C. for 8 hours. The reaction was quenched slowly with aqueous ammonium chloride solution (20 mL), extracted with ethyl acetate (3×50 mL) and the combined organic layer dried over anhydrous sodium sulfate, filtered and concentrated. The crude product was purified by silica gel (100-200) column chromatography using ethyl acetate and hexane gradient elution to afford 7-chloro-1H-pyrrolo[2,3-c]pyridine (0.350 g, 36.45%).

1. customThe resulting reaction mixture
2. stirringby stirring at −20° C. for 8 hours
3. customThe reaction was quenched slowly with aqueous ammonium chloride solution (20 mL)
4. extractionextracted with ethyl acetate (3×50 mL)
5. dry with materialthe combined organic layer dried over anhydrous sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated
8. customThe crude product was purified by silica gel (100-200) column chromatography
9. washethyl acetate and hexane gradient elution

ORD record

ord-101c6e9be45b4f94b41b0dbd61d25864

Source dataset

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08980911B2