反应详情

A mixture of 3 g of 4-cyano-2,2-bisfluoromethyl-6-nitro-2H-1-benzopyran and 20 ml of sulfuric acid was stirred for 36 hours. The reaction mixture was poured into ice water and the separated crystal was collected by filtration. The above-obtained crystal was diluted with ethyl acetate and the organic layer was washed with water and dried. The solvent was distilled off to obtain 3 g of 2,2-bisfluoromethyl-6-nitro-2H-1-benzopyran-4-carboamide represented by the following formula.

1. filtrationthe separated crystal was collected by filtration
2. additionThe above-obtained crystal was diluted with ethyl acetate
3. washthe organic layer was washed with water
4. customdried
5. distillationThe solvent was distilled off