반응 #50207

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Bromine

5-(2-ethoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one

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5-(5-Bromo-2-ethoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one

용매

acetic acid

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후처리

1. 1
   기타the solvent was then removed by evaporation under vacuum
2. 2
   workup.DISSOLUTIONThe residue was dissolved in a 9:1 mixture of methanol in dichloromethane (50 ml)
3. 3
   세척the solution washed with saturated aqueous sodium bicarbonate solution (50 ml), water (50 ml) and saturated brine (50 ml)
4. 4
   건조dried (MgSO4)
5. 5
   기타evaporated under vacuum
6. 6
   기타The residue was chromatographed on silica gel (15 g)
7. 7
   세척eluting with a mixture of methanol and dichloromethane (1:99)
8. 8
   기타to give
9. 9
   기타after crystallisation from acetonitrile

실험 절차

Bromine (0.93 g, 0.0058 mol) was added dropwise to a stirred solution of 5-(2-ethoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one (Preparation 7, 1.1 g, 0.00352 mol) in glacial acetic acid (20 ml). The mixture was stirred at 100° C. for 6.5 hours and the solvent was then removed by evaporation under vacuum. The residue was dissolved in a 9:1 mixture of methanol in dichloromethane (50 ml), and the solution washed with saturated aqueous sodium bicarbonate solution (50 ml), water (50 ml) and saturated brine (50 ml), then dried (MgSO4) and evaporated under vacuum. The residue was chromatographed on silica gel (15 g) eluting with a mixture of methanol and dichloromethane (1:99) to give, after crystallisation from acetonitrile, the title compound (0.62 g, 45%), m.p. 157°-159° C. Found: C,52.41; H,5.25; N,14.01. C17H19BrN4O2 requires C, 52.18; H,4.89; N,14.32%.

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