反应详情

温度

137 °C

400 g (2.03 mol) of crude 2,4,-dichloro-5-thiazolecarboxaldehyde oxime (IV) are stirred with 2 liters of acetic anhydride at reflux temperature (137° C.) for 4 hours. Fractionation using a silvered distillation column 1 m long provided 271 g (=75.7% of theory) of 2,4-dichloro-5-thiazolecarbonitrile (V) at 112° C./20 m bar, this product being identical by mass and IR spectroscopy with that described in German Offenlegungsschrift No. 3,038,608 (which can also be named 2,4-dichloro-5-cyanothiazole). The compound solidifies at room temperature to give colourless crystals which can be recrystallized from petroleum ether. Melting point: 34°-35° C.

1. distillationa silvered distillation column 1 m long provided 271 g (=75.7% of theory) of 2,4-dichloro-5-thiazolecarbonitrile (V) at 112° C./20 m bar
2. customsolidifies at room temperature
3. customto give colourless crystals which
4. customcan be recrystallized from petroleum ether