Reaktion #83216

Reaktionsgleichung

5-amino-3-(4-fluorophenyl)-4-(pyridin-4-yl)pyrazole

hydrochloric acid

1,1,3,3-tetramethoxypropane

sodium bicarbonate

→

2-(4-fluorophenyl)-3-(pyridin-4-yl)pyrazolo[1,5-a]pyrimidine

Ausbeute 87.6%

Lösungsmittel

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was refluxed for one hour
2. 2
   Temperaturcooled
3. 3
   ExtraktionThe separated oil was extracted with dichloromethane
4. 4
   WaschenThe extract was washed with brine
5. 5
   Sonstigedried
6. 6
   Einengenconcentrated in vacuo
7. 7
   SonstigeThe residue was crystallized from a mixture of ethyl acetate and diethyl ether

Vorschrift

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).

Quelle