2-Chlorobenzoxazole → 2-(2-Methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethoxy)benzoxazole

Participants

Reaction Conditions

Reaction Steps

Sodium hydride (77 mg, 1.9 mmol) was added to a solution of 2-hydroxymethyl-2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazole prepared in Example 33 (0.32 g, 1.6 mmol) in DMF (3 ml) with cooling on ice-bath followed by stirring at 0° C. for 30 minutes. To the reaction mixture, 2-chlorobenzoxazole (0.30 g, 1.9 mmol) in DMF (3 ml) was added with cooling on ice-bath followed by stirring at room temperature for 44 hours. Ice-water was added to the reaction mixture, and the resulting mixture was extracted with ethyl acetate. The organic phase was washed with water, dried over magnesium sulfate and then concentrated. The residue was purified by silica gel column chromatography (methylene chloride/methanol=100/1) and recrystallized from acetonitrile-isopropanol to afford 2-(2-methyl-6-nitro-2,3-dihydroimidazo[2,1-b]oxazol-2-ylmethoxy)benzoxazole (0.20 g, 39%) as a light yellow solid.

Provenance & Evidence