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

Temperature

-20 °C

To a solution of 4-chloro-3-nitro-pyridine (2 g, 13 mmol) in dry THF (100 mL) under N2 at −78° C. was added excess vinyl magnesium bromide (1.0M, 40 mL, 40 mmol). The mixture was stirred at −20° C. for 8 hours before the reaction was quenched with 20% NH4Cl (75 mL). The aqueous phase was extracted with ethyl acetate (3×100 mL). The combined organic layer was dried over MgSO4, filtered and concentrated. The residue was subject to chromatography on silica gel to afford 7-Chloro-1H-pyrrolo[3,2-b]pyridine (0.3 g, 16%). 1H NMR (CD3OD, 400 Hz) δ 8.22 (d, J=5.2 Hz, 1H), 7.64 (d, J=3.2 Hz, 1H), 7.23 (d, J=5.2 Hz, 1H), 6.67 (d, J=3.2 Hz, 1H). MS (ESI+) [M+H]+ 153.

1. customwas quenched with 20% NH4Cl (75 mL)
2. extractionThe aqueous phase was extracted with ethyl acetate (3×100 mL)
3. dry with materialThe combined organic layer was dried over MgSO4
4. filtrationfiltered
5. concentrationconcentrated

ORD record

ord-7e20ceaa0bd84733915d57f30c8963ee

Source dataset

uspto-grants-2014_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08680114B2