反应详情

温度

100 °C

(3E)-1-Chloro-4-ethoxy-1,1-difluorobut-3-en-2-one (7.36 g, 40 mmol) was dissolved in dry toluene (40 mL) and treated with 3-dimethylaminoacrylonitrile (4.61 g, 48 mmol) at room temperature. The solution was heated at about 100° C. for 3.5 hr. The solvent was then removed under reduced pressure and the remaining mixture was re-dissolved in dimethyl formamide (DMF; 20 mL), treated with ammonium acetate (4.62 g, 60 mmol) and stirred at room temperature overnight. Water was added to the reaction mixture and the resulting mixture was extracted with ether-CH2CH2 (1:2, v/v) twice. The combined organic layer was washed with brine, dried, filtered and concentrated. The residue was purified on silica gel to give 3.1 g of 6-[chloro(difluoro)methyl]nicotinonitrile (A) as light colored oil in 41% yield. GC-MS: mass calcd for C7H3ClF2N2 [M]+ 188. Found 188.

1. customThe solvent was then removed under reduced pressure
2. dissolutionthe remaining mixture was re-dissolved in dimethyl formamide (DMF; 20 mL)
3. extractionthe resulting mixture was extracted with ether-CH2CH2 (1:2
4. washThe combined organic layer was washed with brine
5. customdried
6. filtrationfiltered
7. concentrationconcentrated
8. customThe residue was purified on silica gel