Reaction #657329

Reaction equation

N-acetyl-N-[4-(2-phenylpyrazolo[1,5-a]pyrimidin-3-yl)pyridin-2-yl]acetamide

ethanol

sodium borohydride

water

→

N-acetyl-N-[4-(4-acetyl-2-phenyl-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)pyridin-2-yl]acetamide

Yield 46.0%

Conditions

Workup

1. 1
   TemperatureThe mixture is refluxed for 1 h
2. 2
   Extractionextracted with dichloromethane (3×50 mL)
3. 3
   Dryingdried over anhydrous magnesium sulphate
4. 4
   Filtrationfiltered
5. 5
   Concentrationconcentrated under reduced pressure
6. 6
   OtherThe crude material is purified by column chromatography

Procedure

To a mixture of N-acetyl-N-[4-(2-phenylpyrazolo[1,5-a]pyrimidin-3-yl)pyridin-2-yl]acetamide (158 mg, 0.43 mmol, 1 eq) in 3 mL of ethanol is added sodium borohydride (35 mg, 0.94 mmol, 2.2 eq). The mixture is refluxed for 1 h. The mixture is then poured into water, extracted with dichloromethane (3×50 mL), dried over anhydrous magnesium sulphate, filtered and concentrated under reduced pressure. The crude material is purified by column chromatography using silica gel in heptane and ethyl acetate (1:0 to 0:1) as eluent and 66 mg (46%) of N-acetyl-N-[4-(4-acetyl-2-phenyl-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)pyridin-2-yl]acetamide are obtained as a white solid.

Source