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

Temperature

-78 °C

A solution of 2-chloro-3-nitropyridine (31.5 mmol) in dry THF (200 mL) was cooled to −78° C. Vinylmagnisium bromide (1.0 M in THF, 100 mL) was added dropwise under N2. The mixture was stirred at −78° C. for 1 hr, followed by −20° C. for further 8 hrs. The mixture was quenched with 150 mL NH4Cl (20% in H2O) and extracted with EtOAc (3×150 mL). The organic layers were combined, washed with brine, dried on MgSO4 and filtered. The solvent was evaporated and the residue was purified by column chromatography using EtOAc/PE (1:3, v/v) to elute 7-chloro-1H-pyrrolo[2,3-c]pyridine as white solid (1.77 g, yield 37%). 1H-NMR (DMSO-d6) δ: 6.63 (d, 1H, J=3.2 Hz, Ar—H), 7.58 (d, 1H, J=5.6 Hz, Ar—H), 7.66 (d, 1H, J=2.8 Hz, Ar—H), 7.90 (d, 1H, J=5.2 Hz, Ar—H). MS (ESI+) m/z 153.0260 (M+H)+.

1. waitfollowed by −20° C. for further 8 hrs
2. customThe mixture was quenched with 150 mL NH4Cl (20% in H2O)
3. extractionextracted with EtOAc (3×150 mL)
4. washwashed with brine
5. customdried on MgSO4
6. filtrationfiltered
7. customThe solvent was evaporated
8. customthe residue was purified by column chromatography

ORD record

ord-bc5b40dc97634ba4be66649d50a26c69

Source dataset

uspto-grants-2012_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08309550B2