反应详情

Methanesulfonyl chloride (1.4 ml, 18.09 mmol) in methylene chloride (10 ml) was added dropwise to a mixture of 2-methyl-2-(3-hydroxypropyl)-6-nitro-2,3-dihydroimidazo[2,1-b]oxazole prepared in Example 38 (2.1 g, 9.24 mmol), triethylamine (2.8 g, 20.09 mmol), 4-dimethylaminopyridine (50 mg, 0.41 mmol) and methylene chloride (80 ml) with cooling on ice-bath followed by stirring at room temperature overnight. The reaction mixture was concentrated. 10% hydrochloric acid was added to the residue, and the resulting mixture was stirred for 30 minutes with cooling on ice-bath. The precipitates were filtered off and washed with water to afford 3-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-yl)propyl methanesulfonate (2.6 g, yield 92%) as a white powder.

1. temperaturewith cooling on ice-bath
2. concentrationThe reaction mixture was concentrated
3. addition10% hydrochloric acid was added to the residue
4. stirringthe resulting mixture was stirred for 30 minutes
5. temperaturewith cooling on ice-bath
6. filtrationThe precipitates were filtered off
7. washwashed with water