Water → (3S)-1-Benzyl-3-ethylpiperazine

HRID 989010Notes

Reaction equation

HRID 989010 reaction equation
[CH2:1]([C@H:3]1[C:8](=O)[N:7]([CH2:10][C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=2)[CH2:6][C:5](=O)[NH:4]1)[CH3:2].[H-].[Al+3].[Li+].[H-].[H-].[H-].O.[OH-].[Na+]>O1CCCC1>[CH2:1]([C@H:3]1[CH2:8][N:7]([CH2:10][C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=2)[CH2:6][CH2:5][NH:4]1)[CH3:2]

Participants

6

Reactant 4

HCID 962Water2×HCID 14798Sodium HydroxideHCID 20598791(S)-1-Benzyl-3-ethylpiperazine-2,5-dioneHCID 21226445Aluminium lithium hydride

Product 1

HCID 17750461(3S)-1-Benzyl-3-ethylpiperazineYield 99%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A solution of 8.1 gm (34.9 mmol) 2(S)-ethyl-4-benzyl-3,6-dioxopiperazine in 50 mL tetrahydrofuran was added dropwise via addition funnel to a solution of 75 mL (75 mMol) lithium aluminum hydride (1M in tetrahydrofuran) and the mixture was heated at reflux for 2.5 h. The reaction was then cooled in an ice bath and was treated sequentially with 3 mL deionized water, 3 mL 5N sodium hydroxide, and 9 mL deionized water. The resulting slurry was allowed to stir for 1 hour and was then filtered. The recovered salts were rinsed with 100 mL tetrahydrofuran and 100 mL dichloromethane. The filtrate was concentrated in vacuo to afford 7.03 g (99%) of the desired piperazine.

Workup

  1. temperaturethe mixture was heated
  2. temperatureat reflux for 2.5 h
  3. temperatureThe reaction was then cooled in an ice bath
  4. additionwas treated sequentially with 3 mL
  5. filtrationwas then filtered
  6. washThe recovered salts were rinsed with 100 mL tetrahydrofuran and 100 mL dichloromethane
  7. concentrationThe filtrate was concentrated in vacuo

Sources & evidence

ORD record
ord-7ec84b5fdd3e4de2acd03db15d2521c0
Source dataset
uspto-grants-2003_10
Patent number
US06638936B1

Reaction notes

Loading…