反应详情

温度

70 °C

To a 1000 ml autoclave, 70.0 g the said rectified 2,5-dimethylbenzyl chloride, 137.5 g triethylamine, 0.3 g palladium(II)bis(triphenylphosphine) dichloride, 81 g water and 168.0 g tert-pentanol are added. Nitrogen is inflated to replace the air for three times and the temperature is raised to 70° C. At 70° C.˜75° C., carbon monoxide is inflated until the pressure is not decreasing. After the reaction has finished, it is cooled to 40° C., then the pressure is relieved, and nitrogen is inflated to replace the air for three times again, the reaction solution is transferred into a 1000 ml four-neck flask and then 120.0 g 30% liquid caustic soda is added under the protection of nitrogen, which is stirred for 1 h at 60° C., then standing for layering. The upper layer is organic layer and the lower layer is water layer. 57.6 g 36% hydrochloric acid is added dropwise into the water layer until pH=1. The solution is kept warm for 1 h and filtered, dried under vacuum to give 64.4 g 2,5-dimethylphenylacetic acid (87.2% yield). Finally, small amount of heavy metal capture agent and flocculant can be added into the filtrate and filtered again to give the catalyst. The gained catalyst after filtering can be recycled and reused.

1. customAt 70° C.˜75° C.
2. temperatureit is cooled to 40° C.
3. customthe reaction solution is transferred into a 1000 ml four-neck flask
4. temperatureThe solution is kept warm for 1 h
5. filtrationfiltered
6. customdried under vacuum