Benzyl Bromide → 1,2,4,7-Tetrahydro-5-methyl-7-(3-nitrophenyl)-2-oxo-1-(phenylmethyl)pyrazolo[1,5-a]pyrimidine-6-carboxylic acid, 1-methylethyl ester

HRID 1252991Notes

Reaction equation

HRID 1252991 reaction equation
[H-].[Na+].[CH3:3][C:4]1[NH:5][C:6]2[N:7]([NH:25][C:26](=[O:28])[CH:27]=2)[CH:8]([C:16]2[CH:21]=[CH:20][CH:19]=[C:18]([N+:22]([O-:24])=[O:23])[CH:17]=2)[C:9]=1[C:10]([O:12][CH:13]([CH3:15])[CH3:14])=[O:11].[CH2:29](Br)[C:30]1[CH:35]=[CH:34][CH:33]=[CH:32][CH:31]=1>CN(C)C=O>[CH3:3][C:4]1[NH:5][C:6]2[N:7]([N:25]([CH2:29][C:30]3[CH:35]=[CH:34][CH:33]=[CH:32][CH:31]=3)[C:26](=[O:28])[CH:27]=2)[CH:8]([C:16]2[CH:21]=[CH:20][CH:19]=[C:18]([N+:22]([O-:24])=[O:23])[CH:17]=2)[C:9]=1[C:10]([O:12][CH:13]([CH3:15])[CH3:14])=[O:11]

Participants

5

Reactant 3

HCID 7498Benzyl BromideHCID 24758Sodium hydrideHCID 141304321,2,4,7-Tetrahydro-5-methyl-7-(3-nitrophenyl)-2-oxopyrazolo[1,5-a]pyrimdine-6-carboxylic acid, 1-methylethyl ester

Product 1

HCID 141304331,2,4,7-Tetrahydro-5-methyl-7-(3-nitrophenyl)-2-oxo-1-(phenylmethyl)pyrazolo[1,5-a]pyrimidine-6-carboxylic acid, 1-methylethyl ester

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent2×

Conditions

Temperature
0 °C

Procedure

To a suspension of sodium hydride (30 mg; 60% dispersion; 0.75 mmole) in dry dimethylformamide (4 ml) was added 1,2,4,7-tetrahydro-5-methyl-7-(3-nitrophenyl)-2-oxopyrazolo[1,5-a]pyrimidine-6-carboxylic acid, 1-methylethyl ester (180 mg; 0.5 mmole) in dimethylformamide (3 ml) at 0° C. under argon. The orange reaction mixture was allowed to stir at 0° C. for 30 minutes and benzyl bromide (70 μl; 0.6 mmole) was then added. The reaction was stirred at room temperature for one hour and then quenched with water. The resulting solution was extracted with ethyl acetate and the combined extracts were washed with water, sodium bicarbonate and brine. After drying over anhydrous magnesium sulfate, the solvent was evaporated to give a foam which was purified by preparative thin layer chromatography (40% ethyl acetate in hexanes) and the product was crystallized from dichloromethane-isopropyl ether to give a solid, melting point 183.5°-185° C.

Workup

  1. stirringThe reaction was stirred at room temperature for one hour
  2. customquenched with water
  3. extractionThe resulting solution was extracted with ethyl acetate
  4. washthe combined extracts were washed with water, sodium bicarbonate and brine
  5. dry with materialAfter drying over anhydrous magnesium sulfate
  6. customthe solvent was evaporated
  7. customto give a foam which
  8. customwas purified by preparative thin layer chromatography (40% ethyl acetate in hexanes)
  9. customthe product was crystallized from dichloromethane-isopropyl ether
  10. customto give a solid, melting point 183.5°-185° C.

Sources & evidence

ORD record
ord-4fb7e175000847f68408346a254145de
Source dataset
uspto-grants-1988_05
Patent number
US04746656

Reaction notes

Loading…