反应详情

To a solution of 5-(5-bromo-2-n-propoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one (1.0 g, 0.0025 mol) and triethylamine (0.38 g, 0.0038 mol) in acetonitrile (2 ml), was added palladium(II) acetate (0.03 g, 0.00013 mol), tri-o-tolylphosphine (0.076 g, 0.00025 mol) and t-butyl acrylate (0.48 g, 0.00038 mol). The mixture was heated under reflux for 4 hours, then cooled and evaporated under vacuum. The residue was suspended in water (30 ml) and extraction with dichloromethane (3×20 ml) effected. The organic extracts were combined, dried (Na2SO4) and evaporated under vacuum to give a yellow-green solid. Chromatography on silica gel (12 g), using a methanol in dichloromethane elution gradient (0-2% methanol), followed by crystallisation from ethyl acetate-hexane gave the title compound as a white solid (0.65 g, 58%), m.p. 167°-168° C. Found: C,66.47; H,7.00; N,12.31. C25H32N4O4 requires C,66.35; H,7.13; N,12.38%.

1. temperatureThe mixture was heated
2. temperatureunder reflux for 4 hours
3. temperaturecooled
4. customevaporated under vacuum
5. extractionextraction with dichloromethane (3×20 ml)
6. dry with materialdried (Na2SO4)
7. customevaporated under vacuum
8. customto give a yellow-green solid
9. washa methanol in dichloromethane elution gradient (0-2% methanol)
10. customfollowed by crystallisation from ethyl acetate-hexane