反应详情

A suspension of 0.91 g (3.14 mmol) of 3-benzenesulphonyl-5-methyl-pyrazolo[1,5-a]pyrimidine in 15 ml of POCl3 was heated at reflux for 1 hr. The reaction solution was cooled to RT and evaporated. The residue was treated with 30 ml of ice-water and the pH value of the solution was adjusted to 8 with sat. NaHCO3 solution. The aqueous phase was extracted three times with 20 ml of CH2Cl2, and the organic phases were dried (MgSO4), filtered and evaporated. Chromatography (SiO2, CH2Cl2/AcOEt 19:1) of the residue yielded 0.84 g (87%) of 3-benzenesulphonyl-7-chloro-5-methyl-pyrazolo[1,5-a]pyrimidine as a beige solid.

1. temperaturewas heated
2. temperatureat reflux for 1 hr
3. customevaporated
4. additionThe residue was treated with 30 ml of ice-water
5. extractionThe aqueous phase was extracted three times with 20 ml of CH2Cl2
6. dry with materialthe organic phases were dried (MgSO4)
7. filtrationfiltered
8. customevaporated