Bromine → 5-(5-Bromo-2-ethoxyphenyl)-1-methyl-3-propyl-1H-pyrazolo[4,3-D]pyrimidin-7(6H)-one

HRID 21929Notes

Reaction equation

HRID 21929 reaction equation
[Br:1]Br.[CH2:3]([O:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][C:7]=1[C:12]1[NH:13][C:14](=[O:25])[C:15]2[N:20]([CH3:21])[N:19]=[C:18]([CH2:22][CH2:23][CH3:24])[C:16]=2[N:17]=1)[CH3:4]>C(O)(=O)C>[Br:1][C:9]1[CH:10]=[CH:11][C:6]([O:5][CH2:3][CH3:4])=[C:7]([C:12]2[NH:13][C:14](=[O:25])[C:15]3[N:20]([CH3:21])[N:19]=[C:18]([CH2:22][CH2:23][CH3:24])[C:16]=3[N:17]=2)[CH:8]=1

Participants

4

Reactant 2

HCID 24408BromineHCID 1354014775-(2-Ethoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]-7-pyrimidinone

Product 1

HCID 1357385545-(5-Bromo-2-ethoxyphenyl)-1-methyl-3-propyl-1H-pyrazolo[4,3-D]pyrimidin-7(6H)-one

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Conditions

Temperature
100 °C

Procedure

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%.

Workup

  1. customthe solvent was then removed by evaporation under vacuum
  2. dissolutionThe residue was dissolved in a 9:1 mixture of methanol in dichloromethane (50 ml)
  3. washthe solution washed with saturated aqueous sodium bicarbonate solution (50 ml), water (50 ml) and saturated brine (50 ml)
  4. dry with materialdried (MgSO4)
  5. customevaporated under vacuum
  6. customThe residue was chromatographed on silica gel (15 g)
  7. washeluting with a mixture of methanol and dichloromethane (1:99)
  8. customto give
  9. customafter crystallisation from acetonitrile

Sources & evidence

ORD record
ord-af3421124bcf445d9f9676c3302624b3
Source dataset
uspto-grants-1995_06
Patent number
US05426107

Reaction notes

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