Reaktion #1348825

Reaktionsgleichung

3-bromo-5-iodopyridine

tert-butyl piperazine-1-carboxylate

K3PO4

1,2-ethanediol

→

desired product

Ausbeute 37.0%

tert-Butyl 4-(5-Bromopyridin-3-yl)piperazine-1-carboxylate

Ausbeute 37.0%

Lösungsmittel

isopropyl alcohol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Filtrationthe reaction mixture was filtered through celite
2. 2
   EinengenThe filtrate was concentrated in vacuo
3. 3
   Waschenthe solution was washed with saturated NaHCO3
4. 4
   Trocknendried (MgSO4)
5. 5
   Einengenconcentrated
6. 6
   SonstigePurification by flash chromatography on silica gel (20% EtOAc/hexanes to 30% EtOAc/hexanes)

Vorschrift

A solution of 3-bromo-5-iodopyridine (13.0 g, 45.8 mmol), tert-butyl piperazine-1-carboxylate (8.53 g, 45.8 mmol), copper(I) iodide (0.871 g, 4.57 mmol), K3PO4 (19.46 g, 91.68 mmol), 1,2-ethanediol (5.1 mL, 91 mmol) in isopropyl alcohol (80 mL) in a sealed tube was heated at 80° C. in an oil bath for 2 days. After cooling to room temperature, the reaction mixture was filtered through celite. The filtrate was concentrated in vacuo. The residue was taken up in EtOAc and the solution was washed with saturated NaHCO3, dried (MgSO4) and concentrated. Purification by flash chromatography on silica gel (20% EtOAc/hexanes to 30% EtOAc/hexanes) afforded 5.75 g (37%) of desired product. MS calculated for C14H20BrN3O2: (M+H) 343; found 342.0, 344.0.

Quelle