1-Methylpiperazine → HCID 9904339, compound

HRID 263906Notes

Reaction equation

HRID 263906 reaction equation
Cl[CH:2]1[C:14]2[NH:13][C:12](=[O:15])[C:11](=[O:16])[NH:10][C:9]=2[C:8]2[CH:7]=[CH:6][CH:5]=[CH:4][C:3]1=2.[CH3:17][N:18]1[CH2:23][CH2:22][NH:21][CH2:20][CH2:19]1>O1CCCC1.C(O)C>[CH3:17][N:18]1[CH2:23][CH2:22][N:21]([CH:2]2[C:14]3[NH:13][C:12](=[O:15])[C:11](=[O:16])[NH:10][C:9]=3[C:8]3[CH:7]=[CH:6][CH:5]=[CH:4][C:3]2=3)[CH2:20][CH2:19]1

Participants

5

Reactant 2

HCID 531671-MethylpiperazineHCID 19035982HCID 19035982, compound

Product 1

HCID 9904339HCID 9904339, compoundYield 38.3%

Reagents, catalysts & solvents 2

HCID 702EthanolSolventHCID 8028TetrahydrofuranSolvent2×

Procedure

9-Chloro-9H-indeno[1,2-b]pyrazine-2,3(1H,4H)-dione (1.50 g, 6.39 mmol) was suspended in 15 ml of dry tetrahydrofuran, while cooling in an ice bath. N-Methylpiperazine (1.42 ml, 12.78 mmol) dissolved in 3 ml of dry tetrahydrofuran was added over 20 min, and the ice bath was removed and stirring was continued for 20 hours at room temperature. The precipitate was filtered off and washed with tetrahydrofuran and dried to give 2.42 g of a remanence, which was dissolved in 100 ml of boiling ethanol, and treated with 300 mg of activated carbon. The mixture was filtered and concentrated to 10 ml. The precipitate was filtered off, washed with ethanol and dried to give 0.65 g of the crude product. From the filtrate another crop of 0.57 g could be isolated. Recrystallization from 6M HCl afforded 0.73 g (30%) of the title compound as a dihydrochloride. M.p. 263°-265° C. 1H-NMR (DMSO-dd6, δ): 2.6 (m, 1H), 2.73 (s, 3H), 2.78-3.52 (m, 7H), 4.84 (s, 1H), 5.9-7.0 (broad, 2H), 7.2 (t, 1H), 7.35 (t, 1H), 7.48 (d, 1H), 7.58 (d, 1H), 10.92 (s, 1H), 11.76 (s, 1H), 12.34 (s, 1H).

Workup

  1. temperaturewhile cooling in an ice bath
  2. additionwas added over 20 min
  3. customthe ice bath was removed
  4. filtrationThe precipitate was filtered off
  5. washwashed with tetrahydrofuran
  6. customdried
  7. customto give 2.42 g of a remanence, which
  8. additiontreated with 300 mg of activated carbon
  9. filtrationThe mixture was filtered
  10. concentrationconcentrated to 10 ml
  11. filtrationThe precipitate was filtered off
  12. washwashed with ethanol
  13. customdried
  14. customto give 0.65 g of the crude product
  15. customFrom the filtrate another crop of 0.57 g could be isolated
  16. customRecrystallization from 6M HCl

Sources & evidence

ORD record
ord-47d86db101384b9f9be769e6192449b1
Source dataset
uspto-grants-1997_07
Patent number
US05646146

Reaction notes

Loading…