Triethylamine → Ethyl 1,4-dibenzylpiperazine-2-carboxylate

HRID 394843

Reaction equation

HRID 394843 reaction equation
Br[CH:2]([CH2:8]Br)[C:3]([O:5][CH2:6][CH3:7])=[O:4].[CH2:10]([NH:17][CH2:18][CH2:19][NH:20][CH2:21][C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1)[C:11]1[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=1.C(N(CC)CC)C>C1(C)C=CC=CC=1>[CH2:10]([N:17]1[CH2:18][CH2:19][N:20]([CH2:21][C:22]2[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=2)[CH2:8][CH:2]1[C:3]([O:5][CH2:6][CH3:7])=[O:4])[C:11]1[CH:12]=[CH:13][CH:14]=[CH:15][CH:16]=1

Participants

5

Reactant 3

HCID 8471TriethylamineHCID 8793BenzathineHCID 97945Ethyl 2,3-dibromopropionate

Product 1

HCID 2736402Ethyl 1,4-dibenzylpiperazine-2-carboxylate

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Conditions

Temperature
80 °C

Procedure

To a stirred solution of ethyl 2,3-dibromopropionate (142.7 g, 0.549 mol) in dry toluene (2000 mL) was added N,N′-dibenzylethylene diamine (132 g, 0.549 mol), followed by triethylamine (110.8 g, 1.098 mol), under N2 at 40° C. (a dense white precipitate formed immediately, thus good stirring was necessary). The mixture was heated at 80° C. overnight, cooled and filtered. The filtrate was then washed with H2O, dried over MgSO4, and concentrated under reduced pressure. The residue oil was taken on to the next step without further purification (GC-MS shows one peak at 6.79) or purified by column chromatography (EtOAc/hexane 1:4). Weight of crude product: 169.6 g (91%).

Workup

  1. customformed immediately
  2. temperaturecooled
  3. filtrationfiltered
  4. washThe filtrate was then washed with H2O
  5. dry with materialdried over MgSO4
  6. concentrationconcentrated under reduced pressure
  7. customThe residue oil was taken on to the next step without further purification (GC-MS shows one peak at 6.79)
  8. custompurified by column chromatography (EtOAc/hexane 1:4)

Sources & evidence

ORD record
ord-2e3192318cb6481abc502dea0f2d66af
Source dataset
uspto-grants-2003_08
Patent number
US06603002B2

Linked notes

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