反应详情

温度

-40 °C

To a solution of 4-bromo-2-methylbenzoic acid (10 g) in tetrahydrofuran (100 mL), a solution of 1.6M n-butyl lithium in hexane (60 mL) was added at −70° C. After the reaction mixture was stirred for one hour at −40° C., a solution of N,N-dimethylformamide (10 mL) in tetrahydrofuran (10 mL) was added to the mixture at −70° C. After stirred for one hour at −70° C. and then warmed to room temperature, the mixture was poured onto ice and diluted with water. The aqueous layer was washed with hexane and acidified with concentrated hydrochloric acid, and the precipitate was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate. The solvent was distilled off under reduced pressure to obtain a crude product of 4-formyl-2-methylbenzoic acid (5 g).

1. stirringAfter stirred for one hour at −70° C.
2. temperaturewarmed to room temperature
3. additionthe mixture was poured onto ice
4. washThe aqueous layer was washed with hexane
5. extractionthe precipitate was extracted with ethyl acetate
6. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
7. distillationThe solvent was distilled off under reduced pressure