反应详情

温度

78 °C

2-(Methylthio)oxazolo[4,5-b]pyridine was prepared according to the procedures of Chu-Moyer and Berger (J. Org. Chem. 1995, 60, 5721-5725) with minor modifications. To a suspension of 2-amino-3-hydroxypyridine (2.8 g, 25 mmol) in EtOH (62 mL, 0.4 M) was added potassium ethyl xanthogenate (8.0 g, 50 mmol, 2 equiv). The reaction mixture was heated to reflux (78° C.) and stirred for a period of 18 hours. The reaction mixture was concentrated to dryness and the resulting residue was dissolved in water (70 mL). Upon acidification to pH 5 with glacial acetic acid, a large quantity of solid precipitated out. The suspension was filtered, washed with water (3×), and dried on the high-vac line overnight to afford 2-thiooxazolo[4,5-b]pyridine as a brown solid (3.3 g, 21.6 mmol, 86%).

1. temperatureThe reaction mixture was heated
2. concentrationThe reaction mixture was concentrated to dryness
3. dissolutionthe resulting residue was dissolved in water (70 mL)
4. customUpon acidification to pH 5 with glacial acetic acid, a large quantity of solid precipitated out
5. filtrationThe suspension was filtered
6. washwashed with water (3×)
7. customdried on the high-vac line overnight