反应详情

温度

70 °C

Under argon, 4.30 g of the compound from Example 3A were initially charged in 100 ml of methanol at 0 to 5° C. 10 ml of thionyl chloride were added dropwise, and the mixture was stirred at 0° C. for 30 minutes and at 70° C. for 24 h. The mixture was then cooled to 5° C. and the precipitate was filtered off with suction. The solution was concentrated using a rotary evaporator and the residue was crystallized using methyl tert-butyl ether. This gave 5.20 g (quantitative, still contains salts) of the title compound.

1. temperatureThe mixture was then cooled to 5° C.
2. filtrationthe precipitate was filtered off with suction
3. concentrationThe solution was concentrated
4. customa rotary evaporator
5. customthe residue was crystallized