Acetic Acid → tert-Butyl 4-[2-amino-4-(methoxycarbonyl)-phenyl]piperazine-1-carboxylate

HRID 1038529Notes

Reaction equation

HRID 1038529 reaction equation
[CH3:1][O:2][C:3]([C:5]1[CH:10]=[CH:9][C:8]([N:11]2[CH2:16][CH2:15][N:14]([C:17]([O:19][C:20]([CH3:23])([CH3:22])[CH3:21])=[O:18])[CH2:13][CH2:12]2)=[C:7]([N+:24]([O-])=O)[CH:6]=1)=[O:4].C(O)(=O)C.O>O1CCOCC1.O.[Fe]>[NH2:24][C:7]1[CH:6]=[C:5]([C:3]([O:2][CH3:1])=[O:4])[CH:10]=[CH:9][C:8]=1[N:11]1[CH2:12][CH2:13][N:14]([C:17]([O:19][C:20]([CH3:23])([CH3:22])[CH3:21])=[O:18])[CH2:15][CH2:16]1

Participants

6

Reactant 3

HCID 176Acetic AcidHCID 962WaterHCID 66598073Tert-butyl 4-[4-(methoxycarbonyl)-2-nitrophenyl]piperazine-1-carboxylate

Product 1

HCID 18526396tert-Butyl 4-[2-amino-4-(methoxycarbonyl)-phenyl]piperazine-1-carboxylateYield 45.2%

Reagents, catalysts & solvents 2

HCID 23925IronCatalystHCID 218864351,4-Dioxane--water (1/1)Solvent

Procedure

To a solution of tert-butyl 4-[4-(methoxycarbonyl)-2-nitrophenyl]piperazine-1-carboxylate (200 mg, 0.547 mmol) in 1,4-dioxane-water (2:1) (6.0 mL), iron powder (76 mg, 1.37 mmol) and acetic acid (1 mL) were added under ice-cold conditions, and the mixture was stirred at room temperature overnight. The reaction solution was added water and a saturated aqueous solution of sodium hydrogen carbonate under ice-cold conditions, filtered through a pad of celite, and extracted with ethyl acetate. Then, the organic layer was washed with brine, dried over anhydrous sodium sulfate, and concentrated in vacuo. The obtained residue was purified by silica-gel column chromatography (hexane/acetone). The title compound (83 mg (yield 45%)) was obtained as a yellow oil.

Workup

  1. filtrationa saturated aqueous solution of sodium hydrogen carbonate under ice-cold conditions, filtered through a pad of celite
  2. extractionextracted with ethyl acetate
  3. washThen, the organic layer was washed with brine
  4. dry with materialdried over anhydrous sodium sulfate
  5. concentrationconcentrated in vacuo
  6. customThe obtained residue was purified by silica-gel column chromatography (hexane/acetone)

Sources & evidence

ORD record
ord-7ddd6f0b8f034c369f2e59a35fadee3f
Source dataset
uspto-grants-2013_10
Patent number
US08551985B2

Reaction notes

Loading…