Reaktion #45143

Reaktionsgleichung

(2S,6R)-2,6-dimethylpiperazine

ethyl-4-fluorobenzoate

→

ethyl 4-((3R,5S)-3,5-dimethylpiperazin-1-yl)benzoate

Ausbeute 71.9%

Lösungsmittel

DMSO

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction mixture was cooled
2. 2
   Sonstigethe solvent evaporated
3. 3
   SonstigeThe crude product was purified by silica column chromatography
4. 4
   Wascheneluting with a gradient of 0 to 10% methanol in dichloromethane containing 1% 0.880 ammonia
5. 5
   SonstigePure fractions were evaporated to dryness

Vorschrift

(2S,6R)-2,6-dimethylpiperazine (6.85 g, 60.00 mmol) was added to ethyl-4-fluorobenzoate (2.20 mL, 15 mmol), in DMSO (40 mL) and warmed to 120° C. under nitrogen. The resulting solution was stirred at 120° C. for 20 h. The reaction mixture was cooled and the solvent evaporated. The crude product was purified by silica column chromatography, eluting with a gradient of 0 to 10% methanol in dichloromethane containing 1% 0.880 ammonia. Pure fractions were evaporated to dryness to afford ethyl 4-((3R,5S)-3,5-dimethylpiperazin-1-yl)benzoate (2.83 g, 71.9%) as a brown oil, which solidified on standing.

Quelle