反应详情

温度

50 °C

A mixture of tert-butyl (S)-[4-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethyl)-piperazin-1-yl]carbamate prepared in Example 503 (300 mg, 0.78 mmol), concentrated hydrochloric acid (2 ml) and methanol (4 ml) was stirred at 50° C. for 30 minutes. The reaction mixture was allowed to return to room temperature and concentrated under reduced pressure. The residue was recrystallized from methanol/ether to afford (S)-[4-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethyl)piperazin-1-yl]amine dihydrochloride (265 mg, yield 91%) as a yellow powder.

1. customto return to room temperature
2. concentrationconcentrated under reduced pressure
3. customThe residue was recrystallized from methanol/ether