反应详情

A suspension of 3.0 g (8.94 mmol) of 3-benzenesulphonyl-5-methyl-2-methylsulphanyl-pyrazolo[1,5-a]pyrimidin-7-ol in 20 ml of POCl3 was heated at reflux for 45 min. The reaction solution was cooled to RT and evaporated in a high vacuum. The residue was treated with 100 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 100 ml of CH2Cl2, and the organic phases were dried (MgSO4), filtered and evaporated. Chromatography (SiO2, CH2Cl2/AcOEt 19:1) of the residue yielded 3.0 g (94%) of 3-benzenesulphonyl-7-chloro-5-methyl-2-methylsulphanyl-pyrazolo[1,5-a]pyrimidine as pale yellow crystals, m.p. 163-165° C.

1. temperaturewas heated
2. temperatureat reflux for 45 min
3. customevaporated in a high vacuum
4. additionThe residue was treated with 100 ml of ice-water
5. extractionThe aqueous phase was extracted three times with 100 ml of CH2Cl2
6. dry with materialthe organic phases were dried (MgSO4)
7. filtrationfiltered
8. customevaporated