反应详情

35.2 g. (0.2 moles) of 3-(phenylmethyl)-1,2,4-oxadiazol-5(4H)-one obtained in Example 1 (a) are dissolved in 100 ml of methanol and 110 ml. (0.22 moles) of 2N sodium methylate solution are added. The solution is evaporated to dryness and the residue is dissolved in 200 ml. of anhydrous dimethylformamide. 35.5 g. (0.25 moles) of methyl iodide are added dropwise while cooling with ice water and stirring. The reaction mixture warms slightly and is stirred overnight at room temperature. The reaction mixture is concentrated and the residue is treated with water and acidified with 2N hydrochloric acid. The crystals are filtered under suction, triturated with sodium bicarbonate solution while still moist, again filtered under suction, and washed with water. 33.6 g. of 4-methyl-3-(phenylmethyl)-1,2,4-oxadiazol-5(4H)-one are obtained, m.p. 105°-107°. After recrystallizing twice from isopropanol the m.p. is 110°-112°.

1. customThe solution is evaporated to dryness
2. dissolutionthe residue is dissolved in 200 ml
3. stirringis stirred overnight at room temperature
4. concentrationThe reaction mixture is concentrated
5. additionthe residue is treated with water
6. filtrationThe crystals are filtered under suction
7. customtriturated with sodium bicarbonate solution while still moist,
8. filtrationagain filtered under suction
9. washwashed with water