Imidazole → 3-[(1H-imidazol-1-yl)methyl]-1,2-benzisoxazole

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Reaction Conditions

Reaction Steps

Sodium hydride (50% in mineral oil, 3.4 g, 0.071 mole) is washed free of mineral oil with hexane (3×30 mL) and suspended in dimethylformamide (100 mL). This suspension is well stirred and maintained near room temperature (water bath) during the dropwise addition of a solution of imidazole (4.8 g, 0.071 mole) in dimethylformamide (25 mL). The reaction mixture is stirred at room temperature for 1 hour when 3-bromomethyl-1,2-benzisoxazole (15.0 g, 0.071 mole) is added all at once. The mixture is then heated at 85° C. for 8 hours. The solvent is evaporated in vacuo and the residue is taken up in methylene chloride (200 mL) and washed with water (3×50 mL). The organic solution is dried over anhydrous sodium sulfate, filtered and evaporated to give 3-[(1H-imidazol-1-yl)methyl]-1,2-benzisoxazole, which is purified by recrystallisation from isopropanol, m.p. 52°-55° C. The free base is converted to the hydrochloride salt m.p. 145°-146° C., when its solution in isopropanol is treated with a small excess of ethereal hydrogen chloride.

Provenance & Evidence