反应详情

Tert-butyl (S)-4-[3-(2-chloro-4-nitroimidazol-1-yl)-2-hydroxy-2-methylpropyl]-piperazine-1-carboxylate prepared in Example 365 (10.25 g, 25.4 mmol) was dissolved in DMF (30 ml). To the solution, sodium hydride (1.12 g, 27.9 mmol) was added followed by stirring for 2 hours with cooling on ice-bath. To the reaction mixture, ethyl acetate (10 ml) and water (70 ml) were added. The precipitates were filtered off, and washed with water. The crude solids were recrystallized from ethyl acetate (70 ml) to afford tert-butyl (S)-4-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethyl)piperazine-1-carboxylate (6.62 g, yield 71%) as a light yellow powder.

1. temperaturewith cooling on ice-bath
2. filtrationThe precipitates were filtered off
3. washwashed with water
4. customThe crude solids were recrystallized from ethyl acetate (70 ml)