Cyclo(-Gly-Phe) → (S)-2-Benzylpiperazine

HRID 737128Notes

Reaction equation

HRID 737128 reaction equation
[CH2:1]([C@@H:8]1[NH:13][C:12](=O)[CH2:11][NH:10][C:9]1=O)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[H-].[Al+3].[Li+].[H-].[H-].[H-]>C1COCC1>[CH2:1]([C@H:8]1[CH2:9][NH:10][CH2:11][CH2:12][NH:13]1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1

Participants

4

Reactant 2

HCID 7076549Cyclo(-Gly-Phe)HCID 21226445Aluminium lithium hydride

Product 1

HCID 20760001(S)-2-BenzylpiperazineYield 80.6%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Conditions

Temperature
0 °C

Procedure

2.3 g of 3-(S)-benzyl-piperazine-2,5-dione were suspended in anhydrous THF under nitrogen and cooled in an ice-bath. 4 equiv. of lithium aluminium hydride were added. The reaction was stirred at 0° C. for 0.5 h, then heated to reflux overnight. The reaction was quenched by the subsequent addition of 1 mL/gLiAlH4 of water, 1 mL/gLiAlH4 of 5% aqueous sodium hydroxide solution and 3 mL/gLiAlH4 of water. The resulting solid were separated by filtration through Celite and rinsed with ethyl acetate. The filtrate was concentrated in vacuo to afford 1.6 g of 2-(S)-benzylpiperazine as yellow oil. ES MS (+) m/z 177

Workup

  1. temperaturecooled in an ice-bath
  2. temperatureheated
  3. temperatureto reflux overnight
  4. customThe reaction was quenched by the subsequent addition of 1 mL/gLiAlH4 of water, 1 mL/gLiAlH4 of 5% aqueous sodium hydroxide solution and 3 mL/gLiAlH4 of water
  5. customThe resulting solid were separated by filtration through Celite
  6. washrinsed with ethyl acetate
  7. concentrationThe filtrate was concentrated in vacuo

Sources & evidence

ORD record
ord-f75f3ff36c944aef8ee7dfaa19ea5ae0
Source dataset
uspto-grants-2009_09
Patent number
US07595397B2

Reaction notes

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