Hydrochloric Acid → 6-Chloro-3-methylimidazo[1,2-a]pyridine-2-carboxylic acid

Temperature

50 °C

To a solution of methyl 6-chloro-3-methylimidazo[1,2-a]pyridine-2-carboxylate (1.01 g, 4.50 mmol) in MeOH (18 mL) at room temperature was added potassium hydroxide (407 mg, 7.25 mmol). The reaction mixture was heated to 50° C. for 15 h, and additional KOH (293 mg) was added. The reaction mixture was heated to reflux for 1 h, cooled to room temperature and 5 M HCl (2.5 mL) was added and the reaction mixture was concentrated. toluene (25 mL) was added to the concentrate and the toluene was evaporated under reduced pressure. This was repeated a second time and the concentrate was dried under high vacuum to give 6-chloro-3-methylimidazo[1,2-a]pyridine-2-carboxylic acid as an off white solid. MS m/z=210.9 [M+H]

1. temperatureThe reaction mixture was heated
2. temperatureto reflux for 1 h
3. temperaturecooled to room temperature
4. concentrationthe reaction mixture was concentrated
5. additiontoluene (25 mL) was added to the
6. concentrationconcentrate
7. customthe toluene was evaporated under reduced pressure
8. customthe concentrate was dried under high vacuum

ORD record

ord-bb286cd4472249ec8b3f3a0975508911

Source dataset

uspto-grants-2016_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09309263B2