Ethylenediamine → 1-Benzyl-3-oxopiperazine

HRID 1981614Notes

Reaction equation

HRID 1981614 reaction equation
ClCC([O:5][CH2:6][CH3:7])=O.[CH2:8]([NH2:11])[CH2:9][NH2:10].C[O-].[Na+].[CH2:15](Cl)[C:16]1[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1.C(=O)([O-])[O-].[Na+].[Na+]>C(O)C.CO>[C:16]1([CH2:15][N:10]2[CH2:9][CH2:8][NH:11][C:6](=[O:5])[CH2:7]2)[CH:21]=[CH:20][CH:19]=[CH:18][CH:17]=1

Participants

8

Reactant 5

HCID 3301EthylenediamineHCID 7503Benzyl ChlorideHCID 7751Ethyl chloroacetateHCID 10340Sodium CarbonateHCID 10942334Sodium Methoxide

Product 1

HCID 114581771-Benzyl-3-oxopiperazine

Reagents, catalysts & solvents 2

HCID 702EthanolSolvent3×HCID 887MethanolSolvent

Procedure

A solution of ethyl chloroacetate (204 g., 1.67 mole) in ethanol (500 ml.) is added to a stirred solution of ethylenediamine (600 g., 10 mole) in ethanol (3 l.) at 0°. After addition is complete the solution is allowed to warm to 20°-25°. After 5 hours a solution of sodium methoxide (90.0 g., 1.67 mole) in methanol (200 ml.) is added and the solution is stirred overnight, filtered to remove inorganic salts and evaporated to remove solvent and unreacted ethylenediamine. The residual oil (189 g.) is added to a mixture of benzyl chloride (241 g., 1.9 mole) anhydrous sodium carbonate (191 g., 2.28 mole) in ethanol (2.3 l.) and the solution is stirred under reflux for 3 hours. The ethanol is removed under reduced pressure and the residue is partitioned between chloroform and water. Evaporation of the chloroform gave a crystalline product which was recrystallized from ethyl acetate to give the title compound, m.p. 154°- 156°.

Workup

  1. additionAfter addition
  2. temperatureto warm to 20°-25°
  3. filtrationfiltered
  4. customto remove inorganic salts
  5. customevaporated
  6. customto remove solvent and unreacted ethylenediamine
  7. stirringthe solution is stirred
  8. temperatureunder reflux for 3 hours
  9. customThe ethanol is removed under reduced pressure
  10. customthe residue is partitioned between chloroform and water
  11. customEvaporation of the chloroform
  12. customgave a crystalline product which
  13. customwas recrystallized from ethyl acetate

Sources & evidence

ORD record
ord-bff7c02001ea4f44b8a714163afb4295
Source dataset
uspto-grants-1986_06
Patent number
US04593098

Reaction notes

Loading…