Nitric Acid → Nitrodenafil

HRID 21959Notes

Reaction equation

HRID 21959 reaction equation
[N+:1]([O-:4])(O)=[O:2].[CH2:5]([O:7][C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][C:9]=1[C:14]1[NH:15][C:16](=[O:27])[C:17]2[N:22]([CH3:23])[N:21]=[C:20]([CH2:24][CH2:25][CH3:26])[C:18]=2[N:19]=1)[CH3:6].O>S(=O)(=O)(O)O>[CH2:5]([O:7][C:8]1[CH:13]=[CH:12][C:11]([N+:1]([O-:4])=[O:2])=[CH:10][C:9]=1[C:14]1[NH:15][C:16](=[O:27])[C:17]2[N:22]([CH3:23])[N:21]=[C:20]([CH2:24][CH2:25][CH3:26])[C:18]=2[N:19]=1)[CH3:6]

Participants

5

Reactant 3

HCID 944Nitric AcidHCID 962WaterHCID 1354014775-(2-Ethoxyphenyl)-1-methyl-3-n-propyl-1,6-dihydro-7H-pyrazolo[4,3-d]-7-pyrimidinone

Product 1

HCID 135566056NitrodenafilYield 61%

Reagents, catalysts & solvents 1

HCID 1118Sulfuric AcidSolvent

Procedure

Concentrated nitric acid (0.5 ml) 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 (2.0 g, 0.0064 mol) in concentrated sulphuric acid (10 ml) at 0° C., and the resulting orange solution was stirred at room temperature for 18 hours. The reaction solution was then added dropwise to stirred ice and water (200 g) and the solid precipitate collected by filtration. This solid was then dissolved in dichloromethane (50 ml) and the solution washed succesively with brine (2×30 ml) and water (30 ml), dried (Na2SO4) and evaporated under vacuum to give a yellow solid. Crystallisation from acetonitrile gave the title compound as yellow needles (1.40 g, 61%), m.p. 214°-216° C. Found: C,57.36; H,5.21; H,19.49. C17H19N5O4 requires C,57.13; H,5.36; N,19.60%.

Workup

  1. additionThe reaction solution was then added dropwise
  2. filtrationthe solid precipitate collected by filtration
  3. dissolutionThis solid was then dissolved in dichloromethane (50 ml)
  4. washthe solution washed succesively with brine (2×30 ml) and water (30 ml)
  5. dry with materialdried (Na2SO4)
  6. customevaporated under vacuum
  7. customto give a yellow solid
  8. customCrystallisation from acetonitrile

Sources & evidence

ORD record
ord-389bfbcb97e54a89a1a5553b60571a25
Source dataset
uspto-grants-1995_06
Patent number
US05426107

Reaction notes

Loading…