(2-Methoxy-5-nitrophenyl)-3-pyrazin-2-yl-urea → 1-(5-Amino-2-methoxyphenyl)-3-pyrazin-2-yl-urea

HRID 1830707Notes

Reaction equation

HRID 1830707 reaction equation
[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([N+:9]([O-])=O)=[CH:5][C:4]=1[NH:12][C:13]([NH:15][C:16]1[CH:21]=[N:20][CH:19]=[CH:18][N:17]=1)=[O:14]>CN(C)C=O.[Pd]>[NH2:9][C:6]1[CH:7]=[CH:8][C:3]([O:2][CH3:1])=[C:4]([NH:12][C:13]([NH:15][C:16]2[CH:21]=[N:20][CH:19]=[CH:18][N:17]=2)=[O:14])[CH:5]=1

Participants

4

Reactant 1

HCID 22046329(2-Methoxy-5-nitrophenyl)-3-pyrazin-2-yl-urea2×

Product 1

HCID 220462781-(5-Amino-2-methoxyphenyl)-3-pyrazin-2-yl-ureaYield 13%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 6228DimethylformamideSolvent

Conditions

Temperature
4 °C

Procedure

A solution of (2-methoxy-5-nitrophenyl)-3-pyrazin-2-yl-urea (Compound 159, Example 3) (16.9 g, 55 mmol) in dimethylformamide (DMF, 320 mL) was shaken under H2 in the presence of palladium on carbon (Pd/C) catalyst (1.6 g, 10% Pd) at 80° C. for 12 h. A second portion of catalyst was added (1.6 g) and shaking was continued for an additional 8 h at the same temperature. The solution was filtered through a pad of celite using an additional 200 mL of DMF. The filtrate was concentrated in vacuo and the residue was triturated with methanol (100 mL). The solid was collected, stirred in boiling methanol, and solids present (1.8 g) were filtered off and discarded. The filtrate was cooled at 4° C. overnight. Solids (1.4 g) were removed by filtration and the filtrate was concentrated in vacuo to a tan solid (2.6 g). The crude solid product was triturated with THF (200 mL), collected by filtration, and dried in vacuo to afford the product as a tan solid (1.85 g, 13%). 1H NMR (300 Mhz, d6 DMSO) δ: 10.10 (s, 1H), 9.94 (br s, 1H), 8.89 (s, 1H), 8.32 (s, 1H), 8.22 (s, 1H), 7.58 (s, 1H), 7.75 (d, 1H), 6.21 (d, 1 H), 4.70 (s, 2H), 3.76 (s, 3H). 13C NMR (75 Mhz, d6-DMSO) δ: 151.4, 149.4, 142.6, 140.9, 139.8, 137.2, 135.2, 128.7, 112.8, 107.7, 106.0, 56.8.

Workup

  1. additionA second portion of catalyst was added (1.6 g)
  2. filtrationThe solution was filtered through a pad of celite
  3. concentrationThe filtrate was concentrated in vacuo
  4. customthe residue was triturated with methanol (100 mL)
  5. customThe solid was collected
  6. stirringstirred
  7. filtrationwere filtered off
  8. customSolids (1.4 g) were removed by filtration
  9. concentrationthe filtrate was concentrated in vacuo to a tan solid (2.6 g)
  10. customThe crude solid product was triturated with THF (200 mL)
  11. filtrationcollected by filtration
  12. customdried in vacuo

Sources & evidence

ORD record
ord-ef03361ea94f4c93a87c0f081975a346
Source dataset
uspto-grants-2006_06
Patent number
US07067506B2

Reaction notes

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