反应详情

Ammonium nitrate (2.82 g, 0.035 mol) and trifluoroacetic anhydride (12.4 ml, 0.088 mol) were added to a solution of 3,4-dimethoxy-2-(2,2,2,-trifluorethoxy)benzonitrile in dichloromethane. The temperature was maintained between 20° C. and 30° C. for 2 hours, after which time the reaction mixture was washed with saturated aqueous sodium bicarbonate solution. The organic layer was separated, dried (MgSO4) and evaporated under reduced pressure. Trituration with diethyl ether followed by filtration afforded a first crop of product. The filtrate was purified on silica gel, eluting with dichloromethane to afford the subtitle compound as a colourless solid (combined yield 6.56 g, 73%). Rf 0.31 (ethyl acetate:hexane 20:80, v/v). MS m/z 324 (MNH4)+.

1. temperatureThe temperature was maintained between 20° C. and 30° C. for 2 hours
2. washafter which time the reaction mixture was washed with saturated aqueous sodium bicarbonate solution
3. customThe organic layer was separated
4. dry with materialdried (MgSO4)
5. customevaporated under reduced pressure
6. filtrationTrituration with diethyl ether followed by filtration
7. customafforded a first crop of product
8. customThe filtrate was purified on silica gel
9. washeluting with dichloromethane