Trifluoroacetic acid → Ethyl 4-(piperazin-1-yl)benzoate

HRID 350544Notes

Reaction equation

HRID 350544 reaction equation
C(OC([N:8]1[CH2:13][CH2:12][N:11]([C:14]2[CH:24]=[CH:23][C:17]([C:18]([O:20][CH2:21][CH3:22])=[O:19])=[CH:16][CH:15]=2)[CH2:10][CH2:9]1)=O)(C)(C)C.C(O)(C(F)(F)F)=O>C(Cl)Cl>[N:11]1([C:14]2[CH:15]=[CH:16][C:17]([C:18]([O:20][CH2:21][CH3:22])=[O:19])=[CH:23][CH:24]=2)[CH2:10][CH2:9][NH:8][CH2:13][CH2:12]1

Participants

4

Reactant 2

HCID 6422Trifluoroacetic acidHCID 11709764tert-Butyl 4-(4-(ethoxycarbonyl)phenyl)piperazine-1-carboxylate

Product 1

HCID 2761178Ethyl 4-(piperazin-1-yl)benzoateYield 100%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

To a stirred solution of ethyl 4-[4-(tert-butyloxycarbonyl)-1-piperazinyl]benzoate (240 mg, 0.718 mmol) in CH2Cl2 (5 mL) was added TFA (5 mL), and the resulting mixture was stirred for 3 hr. The mixture was concentrated in vacuo and the residue was made basic by the addition of sat. NaHCO3, followed by extraction with CHCl3 (2×100 mL). The combined extracts were dried over Na2CO3 and evaporated to give 168 mg ethyl 4-(1-piperazinyl)benzoate (100%) as a yellow oil. 1H-NMR (CDCl3) δ 1.37 (3 H, t, J=7.3 Hz), 3.03 (4 H, t, J=4.9 Hz), 3.29 (4 H, t, J=4.9 Hz), 4.33 (2 H, q, J=7.3 Hz), 6.87 (2 H, dt, J=8.8, 2.4 Hz), 7.91–7.94 (2 H, m).

Workup

  1. concentrationThe mixture was concentrated in vacuo
  2. additionthe residue was made basic by the addition of sat. NaHCO3
  3. extractionfollowed by extraction with CHCl3 (2×100 mL)
  4. dry with materialThe combined extracts were dried over Na2CO3
  5. customevaporated

Sources & evidence

ORD record
ord-cfdaac206e83461f8809f3987085a885
Source dataset
uspto-grants-2007_02
Patent number
US07179819B2

Reaction notes

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