Reaction #657328

Reaction equation

water

acetyl chloride

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

triethylamine

→

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

Yield 37.0%

Solvents

tetrahydrofurane

Conditions

Workup

1. 1
   Extractionextracted with dichloromethane (3×50 mL)
2. 2
   WashThe combined organic layers are washed with a saturated solution of NaHCO3, brine
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 solution of 4-(2-phenylpyrazolo[1,5-a]pyrimidin-3-yl)pyridin-2-amine (420 mg, 1.46 mmol, 1 eq) in 20 mL of tetrahydrofurane is added triethylamine (0.82 mL, 5.85 mmol, 4 eq) and then acetyl chloride (234 mg, 2.92 mmol, 2 eq). The mixture is stirred overnight at room temperature and then poured into water and extracted with dichloromethane (3×50 mL). The combined organic layers are washed with a saturated solution of NaHCO3, brine, 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 0.23 g (37%) of N-acetyl-N-[4-(2-phenylpyrazolo[1,5-a]pyrimidin-3-yl)pyridin-2-yl]acetamide are obtained as a yellow solid.

Source