反应详情

Anhydrous aluminum chloride (1.5 g) was added to tetrahydrofuran (30 ml) with ice bath cooling, followed by a fifteen minute-stirring, addition of sodium azide (1.95 g) and 2-chlorophenylisocyanate (1.53 g) thereto and a sixteen hour-refluxing under heating in that order. After cooling, the reaction mixture was added with stirring to a mixture of sodium nitrite (2 g), water (200 ml) and ice (100 g) and the resulting mixture was acidified with 10% hydrochloric acid (until a potassium iodide starch paper became discolored), followed by extraction with ethyl acetate. The thus obtained ethyl acetate layer was washed with water, dried over sodium sulfate and evaporated under reduced pressure. The resulting residue was purified by flash column chromatography (eluent: hexane: ethyl acetate = 2:1) to obtain the desired 1-(2-chlorophenyl)-5(4H)-tetrazolinone (1.41 g) having a m.p. in the range of from 124.5° to 125.5° C. in a yield of 72% of theory.

1. temperaturecooling
2. waitfollowed by a fifteen minute
3. temperaturea sixteen hour-refluxing
4. temperatureunder heating in that order
5. temperatureAfter cooling
6. additionthe reaction mixture was added
7. extractionfollowed by extraction with ethyl acetate
8. washThe thus obtained ethyl acetate layer was washed with water
9. dry with materialdried over sodium sulfate
10. customevaporated under reduced pressure
11. customThe resulting residue was purified by flash column chromatography (eluent: hexane: ethyl acetate = 2:1)