1,8-Diazabicyclo(5.4.0)undec-7-ene → (R)-2-chloro-1-(2-methyloxiran-2-ylmethyl)-4-nitroimidazole

Participants

Reaction Steps

(R)-2-Chloro-1-(2-hydroxy-3-methanesulfonyloxy-2-methylpropyl)-4-nitroimidazole prepared in Example 11 (942.6 g, 3 mol) was suspended in ethyl acetate (9426 ml). DBU (494 ml, 3.3 mol) was added to the suspension, and the resulting mixture was stirred at room temperature for 1 hour. The reaction mixture was washed with water (5 liters). The water layer was extracted with ethyl acetate (5 liters) twice. The organic phases were combined together, and the mixture was washed with a saturated saline solution (5 liters), dried over magnesium sulfate and then filtered. The filtrate was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (ethyl acetate/n-hexane=1/2) to afford (R)-2-chloro-1-(2-methyloxiran-2-ylmethyl)-4-nitroimidazole (600.7 g, yield 92%) as a white powder.

Provenance & Evidence