1-(2-Nitro-6,7-dihydropyrazolo[1,5-a]pyrazin-5(4H)-yl)ethanone → 1-(2-amino-6,7-dihydropyrazolo[1,5-a]pyrazin-5(4H)-yl)ethanone

HRID 1918808Notes

Reaction equation

HRID 1918808 reaction equation
[N+:1]([C:4]1[CH:15]=[C:7]2[CH2:8][N:9]([C:12](=[O:14])[CH3:13])[CH2:10][CH2:11][N:6]2[N:5]=1)([O-])=O>[Pd].C(O)C>[NH2:1][C:4]1[CH:15]=[C:7]2[CH2:8][N:9]([C:12](=[O:14])[CH3:13])[CH2:10][CH2:11][N:6]2[N:5]=1

Participants

4

Reactant 1

HCID 580439581-(2-Nitro-6,7-dihydropyrazolo[1,5-a]pyrazin-5(4H)-yl)ethanone

Product 1

HCID 580440081-(2-amino-6,7-dihydropyrazolo[1,5-a]pyrazin-5(4H)-yl)ethanoneYield 96.7%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 702EthanolSolvent

Procedure

A 500-mL Parr hydrogenation bottle was charged with 1-(2-nitro-6,7-dihydropyrazolo[1,5-a]pyrazin-5(4H)-yl)ethanone 108b (2.3 g, 10.9 mmol), 10% palladium on carbon (50% wet, 570 mg dry weight) and ethanol (100 mL). The bottle was evacuated, charged with hydrogen gas to a pressure of 50 psi and shaken for 2 h on a Parr hydrogenation apparatus. The catalyst was removed by filtration through a pad of Celite 521 washing with 1:1 CH2Cl2:MeOH (500 mL). The resulting solution was concentrated under reduced pressure to afford a 95% yield (1.9 g) of crude 1-(2-amino-6,7-dihydropyrazolo[1,5-a]pyrazin-5(4H)-yl)ethanone 108c.

Workup

  1. customThe bottle was evacuated
  2. additioncharged with hydrogen gas to a pressure of 50 psi
  3. customThe catalyst was removed by filtration through a pad of Celite 521 washing with 1:1 CH2Cl2
  4. concentrationThe resulting solution was concentrated under reduced pressure

Sources & evidence

ORD record
ord-adf458eb48e84d1eaa374a95f7ed5378
Source dataset
uspto-grants-2013_12
Patent number
US08618107B2

Reaction notes

Loading…