Reaktion #68981

Reaktionsgleichung

1-tert-Butylpiperazine

5-Bromo-2-fluoropyridine

sodium t-butoxide

S-Phos

→

1-tert-butyl-4-(6-fluoropyridin-3-yl)piperazine

Ausbeute 71.0%

Lösungsmittel

ethyl acetate

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   Waschenthe organic phase is washed with water
2. 2
   TrocknenAfter drying over MgSO4
3. 3
   Einengenconcentrating to dryness
4. 4
   Sonstigethe crude product obtained
5. 5
   Sonstigeis chromatographed on silica gel, elution

Vorschrift

1-tert-Butylpiperazine (1.61 g, 11.4 mmol) is placed in 35 ml of toluene under nitrogen, 5-Bromo-2-fluoropyridine (2 g, 11.4 mmol), sodium t-butoxide (1.6 g, 17 mmol), tris(dibenzylideneacetone)dipalladium (0.52 g, 0.57 mmol), and S-Phos (0.93 g, 17 mmol) are then added. The reaction medium is heated at 80° C. for 18 h. After hydrolysis, and extraction with ethyl acetate, the organic phase is washed with water and then with a saturated aqueous sodium chloride solution. After drying over MgSO4, and concentrating to dryness, the crude product obtained is chromatographed on silica gel, elution being carried out with a gradient of methanol in dichloromethane ranging from 0% to 5%. 1.92 g of 1-tert-butyl-4-(6-fluoropyridin-3-yl)piperazine are obtained.

Quelle