反应详情

温度

55 °C

Methyl 4,7-dihydro-2-(hydroxymethyl)-7-oxo-s-triazolo[1,5-a]pyrimidine-5-carboxylate (2.5 g) (11.1 mmol) are suspended in 20 ml of dichloromethane. After the addition of 1.76 g (22.3 mmol) of pyridine and 2.27 g (22.2 mmol) of acetic anhydride the mixture is stirred at 55° C. for 8 hours. The mixture is concentrated in a vacuum and the product is precipitated with diethyl ether. After recrystallization from methanol there are obtained 1.2 g of methyl 2-(acetoxymethyl)-4,7-dihydro-7-oxo-s-triazolo[1,5-a]pyrimidine-5-carboxylate as white crystals of melting point 260° C.

1. concentrationThe mixture is concentrated in a vacuum
2. customthe product is precipitated with diethyl ether
3. customAfter recrystallization from methanol