Hydrochloric Acid → 6-Chlorothiazolo[5,4-b]pyridin-2(1H)-one

Participants

Reaction Conditions

Reaction Steps

3-Amino-5-chloro-2-mercaptopyridine (18.8 g) was added to an ice-cooled solution of phosgene (30 g) in toluene (350 ml). 10% Aqueous solution of sodium hydroxide (300 ml) was added dropwise to the stirred mixtured for a period of 1 hour below 20° C. The final mixture was stirred for 1.5 hous at ambient temperature and then stirred for an additional 1 hour at 50° C. After cooling, the aqueous layer was adjusted to pH 4.0 with 4N hydrochloric acid. The precipitates were collected by filtration, washed with water and dried over phosphorus pentoxide to give white powder of 6-chloro-2-oxo-1,2-dihydrothiazolo[5,4-b]pyridine (15.08 g).

Provenance & Evidence