Piperazine → 2-Nitro-5-piperazinylbenzaldehyde hydrochloride

HRID 1649196Notes

Reaction equation

HRID 1649196 reaction equation
C(O[CH:4]([O:15]CC)[C:5]1[CH:10]=[C:9]([Cl:11])[CH:8]=[CH:7][C:6]=1[N+:12]([O-:14])=[O:13])C.[NH:18]1[CH2:23][CH2:22][NH:21][CH2:20][CH2:19]1>CN(C)C=O>[ClH:11].[N+:12]([C:6]1[CH:7]=[CH:8][C:9]([N:18]2[CH2:23][CH2:22][NH:21][CH2:20][CH2:19]2)=[CH:10][C:5]=1[CH:4]=[O:15])([O-:14])=[O:13]

Participants

4

Reactant 2

HCID 4837PiperazineHCID 132362995-Chloro-2-nitrobenzaldehyde diethyacetal

Product 1

HCID 132363002-Nitro-5-piperazinylbenzaldehyde hydrochlorideYield 64.4%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Conditions

Temperature
80 °C

Procedure

2-Nitro-5-chlorobenzaldehyde diethyl acetal (138 g) was dissolved in 750 ml of dimethylformamide (DMF) and to the solution was added 250 g of anhydrous piperazine and stirred at 80° C. for 4 hours. After removing excessive piperazine and DMF by evaporation under reduced pressure, and a dilute aqueous sodium hydroxide solution was added to the residue to dissolve. Then, the solution was extracted with methylene chloride. The methylene chloride layer was washed with water and dried over sodium sulfate followed by removal of the solvent by distillation. To the residue was added 850 ml of isopropyl alcohol to dissolve, and to the solution was added 65 ml of concentrated hydrochoric acid and heated under reflux for 1 hour. After cooling, the crystals which precipitated were collected by filtration to give 93 g of 2-nitro-5-piperazinylbenzaldehyde hydrochloride, m.p. 195°-201° C.

Workup

  1. customAfter removing excessive piperazine and DMF
  2. customby evaporation under reduced pressure
  3. additiona dilute aqueous sodium hydroxide solution was added to the residue
  4. dissolutionto dissolve
  5. extractionThen, the solution was extracted with methylene chloride
  6. washThe methylene chloride layer was washed with water
  7. dry with materialdried over sodium sulfate
  8. customfollowed by removal of the solvent by distillation
  9. additionTo the residue was added 850 ml of isopropyl alcohol
  10. dissolutionto dissolve
  11. additionto the solution was added 65 ml of concentrated hydrochoric acid
  12. temperatureheated
  13. temperatureunder reflux for 1 hour
  14. temperatureAfter cooling
  15. customthe crystals which precipitated
  16. filtrationwere collected by filtration

Sources & evidence

ORD record
ord-fd58aa7a7f544857a9a592ea9ba71a67
Source dataset
uspto-grants-1983_11
Patent number
US04415572

Reaction notes

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