Benzoyl chloride → 1-Piperazinecarboxylic acid, 4-benzoyl-, 1,1-diMethylethyl ester

HRID 1013065Notes

Reaction equation

HRID 1013065 reaction equation
[C:1]([N:8]1[CH2:13][CH2:12][NH:11][CH2:10][CH2:9]1)([O:3][C:4]([CH3:7])([CH3:6])[CH3:5])=[O:2].[OH-].[Na+].[C:16](Cl)(=[O:23])[C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1>O1CCOCC1.O.[Cl-].[Na+].O>[C:16]([N:11]1[CH2:10][CH2:9][N:8]([C:1]([O:3][C:4]([CH3:7])([CH3:6])[CH3:5])=[O:2])[CH2:13][CH2:12]1)(=[O:23])[C:17]1[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=1

Participants

7

Reactant 3

HCID 7412Benzoyl chlorideHCID 14798Sodium HydroxideHCID 143452tert-Butyl piperazine-1-carboxylate

Product 1

HCID 185197561-Piperazinecarboxylic acid, 4-benzoyl-, 1,1-diMethylethyl esterYield 90%

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 312751,4-DioxaneSolvent2×HCID 57417360Sodium chloride; waterSolvent

Procedure

To a solution of N-Boc-piperazine (14) (1.00 g, 5.37 mmol) in dioxane (5 mL), a solution of NaOH (0.50 g, 12.9 mmol) in water (5 mL) followed by a solution of benzoyl chloride (0.75 mL, 6.44 mmol) in dioxane (2 mL) under vigorous stirring were added. The reaction mixture was stirred at ambient temperature for 4 hours, diluted with brine (20 mL), and extracted with ethyl acetate (2×25 mL). The organic extract was washed successively with brine (20 mL), saturated NaHCO3 (20 mL), saturated KH2PO4 (20 mL), and dried (Na2SO4). The solvents were evaporated to give the title compound (1.400 g, 90%) which was used in the next step of the synthesis without further purification. 1H NMR (CDCl3, HMDS), δ: 1.41 (s, 9H), 2.86 (t, J=5.0 Hz, 4H); 3.62 (t, J=5.0 Hz, 4H); 7.34 (s, 5H).

Workup

  1. additionwere added
  2. stirringThe reaction mixture was stirred at ambient temperature for 4 hours
  3. extractionextracted with ethyl acetate (2×25 mL)
  4. extractionThe organic extract
  5. washwas washed successively with brine (20 mL), saturated NaHCO3 (20 mL), saturated KH2PO4 (20 mL)
  6. dry with materialdried (Na2SO4)
  7. customThe solvents were evaporated

Sources & evidence

ORD record
ord-ed065e2b6a1b4a89a6369d2f5c1fbfd3
Source dataset
uspto-grants-2011_07
Patent number
US07981895B2

Reaction notes

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