Formic Acid → 6-Chloro-3H-imidazo(4,5-c)pyridine

A mixture of 6-chloropyridine-3,4-diamine (4.00 g, 27.86 mmol) in formic acid (20.0 mL) was heated at reflux overnight. The reaction mixture was concentrated under reduced pressure to give a brown oil, which was partitioned between EtOAc (300 mL) and a sat'd aq NaHCO3 (100 mL). The organic layer was dried (MgSO4), filtered and concentrated under reduced pressure. The residue was purified by SiO2 chromatography eluting with a MeOH/DCM gradient (6% to 9% MeOH) to afford 3.5 g (82%) of 6-chloro-3H-imidazo[4,5-c]pyridine as white solid, MS (ESI): m/z=154.1 [M+1]+.

1. temperaturewas heated
2. temperatureat reflux overnight
3. concentrationThe reaction mixture was concentrated under reduced pressure
4. customto give a brown oil, which
5. customwas partitioned between EtOAc (300 mL)
6. dry with materialThe organic layer was dried (MgSO4)
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure
9. customThe residue was purified by SiO2 chromatography
10. washeluting with a MeOH/DCM gradient (6% to 9% MeOH)

ORD record

ord-c8de8487b2a147cbb340f8525bd6e3f2

Source dataset

uspto-grants-2014_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08815877B2