Dimethylformamide → 4-(3,5,6-Trichloropyridin-2-yl)piperazine-1-carboxylic acid tert-butyl ester

HRID 1804119Notes

Reaction equation

HRID 1804119 reaction equation
Cl[C:2]1[C:7]([Cl:8])=[CH:6][C:5]([Cl:9])=[C:4]([Cl:10])[N:3]=1.[C:11]([N:18]1[CH2:23][CH2:22][NH:21][CH2:20][CH2:19]1)([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12].C(=O)([O-])[O-].[K+].[K+].CN(C)C=O>O.C1(C)C=CC=CC=1>[C:14]([O:13][C:11]([N:18]1[CH2:23][CH2:22][N:21]([C:2]2[C:7]([Cl:8])=[CH:6][C:5]([Cl:9])=[C:4]([Cl:10])[N:3]=2)[CH2:20][CH2:19]1)=[O:12])([CH3:17])([CH3:15])[CH3:16]

Participants

7

Reactant 4

HCID 6228DimethylformamideHCID 11430Potassium CarbonateHCID 169902,3,5,6-TetrachloropyridineHCID 143452tert-Butyl piperazine-1-carboxylate

Product 1

HCID 866587754-(3,5,6-Trichloropyridin-2-yl)piperazine-1-carboxylic acid tert-butyl esterYield 85.6%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 1140TolueneSolvent

Conditions

Temperature
100 °C

Procedure

To a mixture of 2,3,5,6-tetrachloropyridine (6.51 g), 1-Boc-piperazine (6.71 g) and potassium carbonate (9.95 g) were added dimethylformamide (15 mL) and toluene (30 mL), and the mixture was stirred at 100° C. for 2 hr. After cooling, water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine, and dried over sodium sulfate. The solvent was evaporated under reduced pressure and the residue was purified by column chromatography (ethyl acetate:hexane) to give the title compound (9.42 g).

Workup

  1. temperatureAfter cooling
  2. extractionthe mixture was extracted with ethyl acetate
  3. washThe organic layer was washed with saturated brine
  4. dry with materialdried over sodium sulfate
  5. customThe solvent was evaporated under reduced pressure
  6. customthe residue was purified by column chromatography (ethyl acetate:hexane)

Sources & evidence

ORD record
ord-49d385cb3fb24444b4d6d0ba4af67a9a
Source dataset
uspto-grants-2013_01
Patent number
US08354401B2

Reaction notes

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