反应详情

A mixture of 47.4 g of ethyl 2,4-dichloro-5-fluoro-benzoate and 8.2 g of anhydrous acetonitrile are added dropwise to a suspension of 6.1 g of 80% strength sodium hydride in 100 ml of anhydrous tetrahydrofuran under reflux in the course of about 1 hour. The mixture is heated at the boiling point under reflux for a further hour and cooled to room temperature, and 150 ml of ether are added. The precipitate is filtered off with suction and dissolved in 50 ml of ice-water and the solution is acidified to pH=6 with 10% strength hydrochloric acid. The precipitate is filtered off cold with suction, rinsed with ice-water and dried in vacuo at 40° C. 16 g of 2,4-dichloro-5-fluoro-benzoylacetonitrile of melting point 96°-98° C. are obtained.

1. temperatureunder reflux in the course of about 1 hour
2. temperatureThe mixture is heated at the boiling point
3. temperatureunder reflux for a further hour
4. filtrationThe precipitate is filtered off with suction
5. dissolutiondissolved in 50 ml of ice-water
6. filtrationThe precipitate is filtered off cold with suction
7. washrinsed with ice-water
8. customdried in vacuo at 40° C