反应详情

A mixture of 3-formylbenzonitrile (25.00 g), 2,3-butanedione-2-oxime (19.31 g) and 4N hydrogenchloride-ethyl acetate (300 mL) was stirred at room temperature for 15 hrs. The reaction mixture was concentrated and the obtained oily substance was decanted and washed with diethyl ether. A mixture of the obtained residue, tetrahydrofuran (500 mL) and thionyl chloride (34.14 g) was heated under reflux for 2 hrs. The reaction mixture was concentrated and ethyl acetate was added to the residue. The ethyl acetate layer was washed successively with saturated aqueous sodium hydrogen carbonate solution and saturated brine, dried over anhydrous magnesium sulfate and concentrated. The obtained residue was subjected to silica gel column chromatography and eluted with ethyl acetate-hexane (1:2, v/v) to obtain 3-(4-chloromethyl-5-methyl-1,3-oxazol-2-yl)benzonitrile as colorless crystals (12.01 g, yield 27%). Recrystallization from ethyl acetate-hexane gave colorless prism crystals. melting point: 100-101° C.

1. concentrationThe reaction mixture was concentrated
2. customthe obtained oily substance was decanted
3. washwashed with diethyl ether
4. additionA mixture of the obtained residue, tetrahydrofuran (500 mL) and thionyl chloride (34.14 g)
5. temperaturewas heated
6. temperatureunder reflux for 2 hrs
7. concentrationThe reaction mixture was concentrated
8. additionethyl acetate was added to the residue
9. washThe ethyl acetate layer was washed successively with saturated aqueous sodium hydrogen carbonate solution and saturated brine
10. dry with materialdried over anhydrous magnesium sulfate
11. concentrationconcentrated
12. washeluted with ethyl acetate-hexane (1:2