Hydrochloric Acid → HCID 15729166, compound

Participants

Reaction Steps

A mixture of 2-acetamido-5-(2,4-difluorophenylthio)thiazole (14.8 g) in a mixture of ethanol (150 ml) and concentrated hydrochloric acid (15 ml) was refluxed for 1.5 hours with stirring. The reaction mixture was concentrated under reduced pressure and the residue was dissolved in water. The solution was adjusted to pH 12 using aqueous sodium hydroxide with stirring under ice-cooling. The mixture was extracted with ethyl acetate, washed with water and dried over magnesium sulfate. The organic layer was concentrated under reduced pressure to give solid. The solid was subjected to column chromatography on silica gel (silica gel, 230-400 mesh, Nakarai) (300 g) and eluted with a mixture of chloroform and methanol (100:1). The fractions containing the objective compound were combined and evaporated to dryness in vacuo to give 2-amino-5-(2,4-difluorophenylthio)thiazole (6.26 g, yield: 49.6%). mp: 116°-117° C. IR (Nujol): 3410, 3090, 1625, 1600, 1515 cm-1NMR (DMSO-d6, 60 MHZ, ppm): 7.07-7.76 (6H, m) MASS: M+2 246, M 244, m/e 157

Provenance & Evidence