Potassium Carbonate → tert-Butyl 4-(3-phenoxypropyl)piperazine-1-carboxylate

HRID 1053524Notes

Reaction equation

HRID 1053524 reaction equation
[CH3:1][C:2]([O:5][C:6]([N:8]1[CH2:13][CH2:12][NH:11][CH2:10][CH2:9]1)=[O:7])([CH3:4])[CH3:3].C(=O)([O-])[O-].[K+].[K+].Br[CH2:21][CH2:22][CH2:23][O:24][C:25]1[CH:30]=[CH:29][CH:28]=[CH:27][CH:26]=1>CN(C=O)C>[O:24]([CH2:23][CH2:22][CH2:21][N:11]1[CH2:12][CH2:13][N:8]([C:6]([O:5][C:2]([CH3:1])([CH3:3])[CH3:4])=[O:7])[CH2:9][CH2:10]1)[C:25]1[CH:30]=[CH:29][CH:28]=[CH:27][CH:26]=1

Participants

5

Reactant 3

HCID 11430Potassium CarbonateHCID 68522Benzene, (3-bromopropoxy)-HCID 143452tert-Butyl piperazine-1-carboxylate

Product 1

HCID 131736284tert-Butyl 4-(3-phenoxypropyl)piperazine-1-carboxylateYield 85%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a solution of n-Boc-piperazine (1.08 g, 5.80 mmol) in dry DMF (10 mL) were added anhydrous potassium carbonate (4.01 g, 29.04 mmol) and compound 26 (1.5 g, 6.97 mmol). The reaction mixture was stirred at RT for 8 h. The potassium carbonate was removed by suction filtration and the solvent was removed under reduced pressure. The residue was dissolved with water and extracted with ethyl acetate. The combined organic layers were dried over anhydrous sodium sulfate and the solvent was removed by evaporation. The crude product was purified by column chromatography using ethyl acetate:hexane (8:2) to give compound 28 (1.58 g, 85%). 1H NMR (400 MHz, CDCl3) δ 1.39 (s, 9H), 1.92 (s, 2H), 2.36 (s, 4H), 2.48 (s, 2H), 3.39 (s, 4), 3.95 (m, 2), 6.83 (m, 2H), 7.19 (m, 3H).

Workup

  1. customThe potassium carbonate was removed by suction filtration
  2. customthe solvent was removed under reduced pressure
  3. dissolutionThe residue was dissolved with water
  4. extractionextracted with ethyl acetate
  5. dry with materialThe combined organic layers were dried over anhydrous sodium sulfate
  6. customthe solvent was removed by evaporation
  7. customThe crude product was purified by column chromatography

Sources & evidence

ORD record
ord-fd89a888a43e4f8fb2885c43a4febe79
Source dataset
uspto-grants-2016_07
Patent number
US09393306B2

Reaction notes

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