Potassium Carbonate → 1-Boc-4-(2-formylphenyl)piperazine

HRID 974876Notes

Reaction equation

HRID 974876 reaction equation
F[C:2]1[CH:9]=[CH:8][CH:7]=[CH:6][C:3]=1[CH:4]=[O:5].[N:10]1([C:16]([O:18][C:19]([CH3:22])([CH3:21])[CH3:20])=[O:17])[CH2:15][CH2:14][NH:13][CH2:12][CH2:11]1.C([O-])([O-])=O.[K+].[K+]>CN(C=O)C.[Cu]>[C:19]([O:18][C:16]([N:10]1[CH2:15][CH2:14][N:13]([C:2]2[CH:9]=[CH:8][CH:7]=[CH:6][C:3]=2[CH:4]=[O:5])[CH2:12][CH2:11]1)=[O:17])([CH3:22])([CH3:20])[CH3:21]

Participants

6

Reactant 3

HCID 11430Potassium CarbonateHCID 67970o-FluorobenzaldehydeHCID 143452tert-Butyl piperazine-1-carboxylate

Product 1

HCID 64909901-Boc-4-(2-formylphenyl)piperazineYield 49.5%

Reagents, catalysts & solvents 2

HCID 23978CopperCatalystHCID 6228DimethylformamideSolvent

Conditions

Temperature
150 °C

Procedure

To a solution of 1 g (8 mmol) of 2-fluorobenzaldehyde in 14 mL of DMF was added 2.25 g (12.1 mmol) of t-butyl 1-piperazinecarboxylate. The resulting solution was treated with 50 mg (0.8 mmol) of copper powder and 5.1 g (36.3 mmol) of ground K2CO3 and the suspension was heated to 150° C. in a sealed tube. After 18 h, the reaction was cooled and the contents of the tube were partitioned between water and EtOAc. The aqueous layer was reextracted with EtOAc and the organic layers were combined. The organic layer was washed with water, brine and dried. The filtrate was concentrated and the residue was chromatographed on a flash column with 12% EtOAc-Hexane to furnish 1.15 g (49%) of 1-t-butoxycarbonyl-4-(2-formylphenyl)-piperazine.

Workup

  1. temperaturethe reaction was cooled
  2. customthe contents of the tube were partitioned between water and EtOAc
  3. washThe organic layer was washed with water, brine
  4. customdried
  5. concentrationThe filtrate was concentrated
  6. customthe residue was chromatographed on a flash column with 12% EtOAc-Hexane

Sources & evidence

ORD record
ord-be11f2ca3ba94207a32b4737ab405e40
Source dataset
uspto-grants-1997_03
Patent number
US05607936

Reaction notes

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