Piperazine → 1-(5-Trifluoromethyl-pyridin-2-yl)-piperazine

HRID 849489Notes

Reaction equation

HRID 849489 reaction equation
Cl[C:2]1[CH:7]=[CH:6][C:5]([C:8]([F:11])([F:10])[F:9])=[CH:4][N:3]=1.[NH:12]1[CH2:17][CH2:16][NH:15][CH2:14][CH2:13]1>O>[F:9][C:8]([F:11])([F:10])[C:5]1[CH:6]=[CH:7][C:2]([N:12]2[CH2:17][CH2:16][NH:15][CH2:14][CH2:13]2)=[N:3][CH:4]=1

Participants

4

Reactant 2

HCID 4837PiperazineHCID 923422-Chloro-5-(trifluoromethyl)pyridine

Product 1

HCID 6676181-(5-Trifluoromethyl-pyridin-2-yl)-piperazineYield 75.2%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
100 °C

Procedure

A mixture of 2-chloro-5-trifluoromethylpyridine (Aldrich; 2.296 g), piperazine (5.45 g), and water is heated at 100° C. for 16 h. After cooling, the mixture is partitioned between dichloromethane and aq. sodium bicarbonate. The organic layers are dried over sodium sulfate and concentrated. The residue is chromatographed on silica gel using methanol/dichloromethane (8/92) with about 0.5% ammonium hydroxide present, to give 2.20 g of 1-(5-trifluoromethylpyridin-2-yl)piperazine; mp 45-47° C.; IR (mineral oil) 1127, 1323, 1319, 1118, 1614 cm-1 ; 1H NMR (CDCl3) δ 2.98, 3.62, 6.63, 7.62, 8.40.

Workup

  1. temperatureAfter cooling
  2. customthe mixture is partitioned between dichloromethane and aq. sodium bicarbonate
  3. dry with materialThe organic layers are dried over sodium sulfate
  4. concentrationconcentrated
  5. customThe residue is chromatographed on silica gel

Sources & evidence

ORD record
ord-7199c14de3d54236872c03b4bff62e74
Source dataset
uspto-grants-2000_01
Patent number
US06013654

Reaction notes

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