反应详情

To a solution of 5-amino-3-(4-fluorophenyl)-4-(pyridin-4-yl)pyrazole (102 mg) in ethanol (3 ml) were added concentrated hydrochloric acid (50 μl), zinc chloride (27 mg) and 1,1,3,3-tetramethoxypropane (72 mg) in that order. The mixture was refluxed for one hour, cooled, and poured into an aqueous saturated sodium bicarbonate solution. The separated oil was extracted with dichloromethane. The extract was washed with brine, dried and concentrated in vacuo. The residue was crystallized from a mixture of ethyl acetate and diethyl ether to yield 2-(4-fluorophenyl)-3-(pyridin-4-yl)pyrazolo[1,5-a]pyrimidine (102 mg).

1. temperatureThe mixture was refluxed for one hour
2. temperaturecooled
3. extractionThe separated oil was extracted with dichloromethane
4. washThe extract was washed with brine
5. customdried
6. concentrationconcentrated in vacuo
7. customThe residue was crystallized from a mixture of ethyl acetate and diethyl ether