1-Piperazinecarboxylic acid, ethyl ester → ethyl 4-(2-formylphenyl)piperazine-1-carboxylate

HRID 365747Notes

Reaction equation

HRID 365747 reaction equation
F[C:2]1[CH:9]=[CH:8][CH:7]=[CH:6][C:3]=1[CH:4]=[O:5].[CH2:10]([O:12][C:13]([N:15]1[CH2:20][CH2:19][NH:18][CH2:17][CH2:16]1)=[O:14])[CH3:11].C(=O)([O-])[O-].[Ca+2]>CS(C)=O>[CH2:10]([O:12][C:13]([N:15]1[CH2:16][CH2:17][N:18]([C:2]2[CH:9]=[CH:8][CH:7]=[CH:6][C:3]=2[CH:4]=[O:5])[CH2:19][CH2:20]1)=[O:14])[CH3:11]

Participants

5

Reactant 3

HCID 84311-Piperazinecarboxylic acid, ethyl esterHCID 10112Calcium CarbonateHCID 67970o-Fluorobenzaldehyde

Product 1

HCID 2798046ethyl 4-(2-formylphenyl)piperazine-1-carboxylateYield 68%

Reagents, catalysts & solvents 1

HCID 679Dimethyl SulfoxideSolvent

Procedure

2-Fluorobenzaldehyde (3.0 g, 24.2 mmol), 1-(ethoxycarbonyl)piperazine (4.2 ml, 28.7 ml), and calcium carbonate (2.46 g, 24.6 mmol) were reacted at 120° C. for 7.5 hours in dimethylsulfoxide (12 ml). After the reaction was completed, the insolubles were filtered off and the resulting filtrate was extracted by adding water and ethyl acetate thereto. The organic layer was dried over anhydrous magnesium sulfate and concentrated to give oily substances. The resulting oily substances were purified by silica gel column chromatography (eluent: from hexane/ethyl acetate=4/1 to hexane/ethyl acetate=1/1) to give the title compound (4.29 g, 68%).

Workup

  1. filtrationthe insolubles were filtered off
  2. extractionthe resulting filtrate was extracted
  3. additionby adding water and ethyl acetate
  4. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
  5. concentrationconcentrated
  6. customto give oily substances
  7. customThe resulting oily substances were purified by silica gel column chromatography (eluent: from hexane/ethyl acetate=4/1 to hexane/ethyl acetate=1/1)

Sources & evidence

ORD record
ord-921822b21f7c4aa7ae30b99fdaa867de
Source dataset
uspto-grants-2000_10
Patent number
US06127541

Reaction notes

Loading…