反应详情

4 g of sodium nitride was added to 30 ml of concentrated sulfuric acid and chilled to a temperature of 10° C. and 38 ml of acetic acid was added thereto. 8.9 ml of 4-cyano-2,6-difluoroaniline was added gradually to maintain the solution at a temperature of 20° to 25° C. The reaction mixture was added dropwise to a solution a 10 g of copper (I) bromide dissolved in 30 ml of concentrated hydrobromic acid. After the dropwise addition was completed, the reaction mixture was stirred for one and one half hours at room temperature. Water was added to the reaction mixture, the reaction mixture was extracted with chloroform and washed with water. The organic layer was removed by distillation, and the residue was recrystallized with a mixture of methanol and acetone to yield 6.6 g of 2-bromo-5-cyano-1,3-difluorobenzene.

1. additionwas added
2. temperatureto maintain the solution at a temperature of 20° to 25° C
3. additionAfter the dropwise addition
4. extractionthe reaction mixture was extracted with chloroform
5. washwashed with water
6. customThe organic layer was removed by distillation
7. customthe residue was recrystallized with a mixture of methanol and acetone