反应详情

Aluminium trichloride (6.0 g, 0.045 mol) was added portionwise to a stirred solution of 1-methyl-5-(2-n-propoxyphenyl)-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one (5.0 g, 0.0153 mol) and 2-bromoacetyl chloride (2.5 ml, 0.0303 mol) in dichloromethane (100 ml) at 0° C. The reaction mixture was allowed to warm to room temperature, stirred for 18 hours, heated under reflux for 3 hours and then added cautiously to ice and water (100 g). The resulting mixture was stirred for 1 hour and extracted with dichloromethane (2×50 ml). The combined organic extracts were washed with brine (2×50 ml), dried (Na2SO4), then evaporated under vacuum to give an off-white solid, which was triturated with ether to give the title compound as a white solid (4.1 g, 60%). A small sample was crystallised from ethyl acetate-hexane to give the pure product, m.p. 136°-137° C. Found: C,53.82; H,5.24; N,12.57. C20H23BrN4O3 requires C,53.70; H,5.18; N,12.52%.

1. temperatureheated
2. temperatureunder reflux for 3 hours
3. stirringThe resulting mixture was stirred for 1 hour
4. extractionextracted with dichloromethane (2×50 ml)
5. washThe combined organic extracts were washed with brine (2×50 ml)
6. dry with materialdried (Na2SO4)
7. customevaporated under vacuum
8. customto give an off-white solid, which
9. customwas triturated with ether