2-Aminopyridine → 2-Chloromethyl-imidazo(1,2-A)pyridine

Participants

Reaction Steps

The method of Vanelle et al. Tetrahedron 1991, 47, 5173-5184 was used. To a solution of 1,3-dichloro-2-propanone (2.69 g, 21.2 mmol) in 1,2-dimethoxyethane (5 mL) was added 2-aminopyridine and the mixture was stirred at room temperature for 2 hours. During this time a thick precipitate formed, and this was collected by filtration. The precipitate was refluxed in absolute ethanol for 2 hours after which volatiles were removed by evaporation. The residue was dissolved in water (30 mL) and solid NaHCO3 was added to neutralize the mixture. A white precipitate formed, and this was collected by filtration, washed with water and vacuum dried to yield the title compound pure as a cream white solid (1.43 g, 42%). 1H NMR (500 MHz, CDCl3): δ8.08 (d, J=6.7 Hz, 1H), 7.62 (s, 1H), 7.58 (d, J=9.0 Hz, 1H), 7.17-7.22 (m, 1H), 6.80 (t, J=6.8 Hz, 1H), 4.78 (s, 2H).

Provenance & Evidence