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

HRID 21953

Reaction equation

HRID 21953 reaction equation
[Cl-].[Cl-].[Cl-].[Al+3].[CH3:5][N:6]1[C:14]2[C:13](=[O:15])[NH:12][C:11]([C:16]3[CH:21]=[CH:20][CH:19]=[CH:18][C:17]=3[O:22][CH2:23][CH2:24][CH3:25])=[N:10][C:9]=2[C:8]([CH2:26][CH2:27][CH3:28])=[N:7]1.[Br:29][CH2:30][C:31](Cl)=[O:32].O>ClCCl>[Br:29][CH2:30][C:31]([C:20]1[CH:19]=[CH:18][C:17]([O:22][CH2:23][CH2:24][CH3:25])=[C:16]([C:11]2[NH:12][C:13](=[O:15])[C:14]3[N:6]([CH3:5])[N:7]=[C:8]([CH2:26][CH2:27][CH3:28])[C:9]=3[N:10]=2)[CH:21]=1)=[O:32]

Participants

6

Reactant 4

HCID 962WaterHCID 89602Bromoacetyl chlorideHCID 6451240Aluminum(III) ChlorideHCID 1357385471-Methyl-5-(2-propoxyphenyl)-3-propyl-1H-pyrazolo[4,3-d]pyrimidin-7(6H)-one

Product 1

HCID 1361616085-(5-Bromoacetyl-2-n-propoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]-pyrimidin-7-oneYield 60%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

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%.

Workup

  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

Sources & evidence

ORD record
ord-ac6e5907089a45fd8fa2861c6cec197c
Source dataset
uspto-grants-1995_06
Patent number
US05426107

Linked notes

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