Benzyl Bromide → Tert-butyl 4-benzylpiperazine-1-carboxylate

HRID 352776Notes

Reaction equation

HRID 352776 reaction equation
[N:1]1([C:7]([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8])[CH2:6][CH2:5][NH:4][CH2:3][CH2:2]1.[CH2:14](Br)[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1.C(N(CC)CC)C>C(#N)C>[CH2:14]([N:4]1[CH2:5][CH2:6][N:1]([C:7]([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8])[CH2:2][CH2:3]1)[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1

Participants

5

Reactant 3

HCID 7498Benzyl BromideHCID 8471TriethylamineHCID 143452tert-Butyl piperazine-1-carboxylate

Product 1

HCID 584330Tert-butyl 4-benzylpiperazine-1-carboxylate

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

In acetonitrile (80 ml), tert-butyl 1-piperazine carboxylate (2.50 g) was dissolved. Under ice cooling, benzyl bromide (1.59 ml) and triethylamine (1.87 ml) were added dropwise to the resulting solution, followed by stirring at room temperature for 90 minutes. After the solvent was distilled off under reduced pressure, distilled water and dichloromethane were added to the residue to separate the organic layer. The organic layer was washed with saturated aqueous NaCl solution and dried over anhydrous sodium sulfate. The residue obtained by distilling off the solvent under reduced pressure was purified by chromatography on a silica gel column (ethyl acetate:hexane=1:20 to 1:5), whereby the title compound (3.12 g, 84%) was obtained as colorless powder.

Workup

  1. distillationAfter the solvent was distilled off under reduced pressure
  2. distillationdistilled water and dichloromethane
  3. additionwere added to the residue
  4. customto separate the organic layer
  5. washThe organic layer was washed with saturated aqueous NaCl solution
  6. dry with materialdried over anhydrous sodium sulfate
  7. customThe residue obtained
  8. distillationby distilling off the solvent under reduced pressure
  9. customwas purified by chromatography on a silica gel column (ethyl acetate:hexane=1:20 to 1:5), whereby the title compound (3.12 g, 84%)
  10. customwas obtained as colorless powder

Sources & evidence

ORD record
ord-db6b2e86d50d483baa4043eb53a4adb0
Source dataset
uspto-grants-2004_06
Patent number
US06747023B1

Reaction notes

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