Reaktion #156309

Reaktionsgleichung

6-bromo-3-fluoro-2-methylpyridine

tert-butyl (3R)-3-methylpiperazine-1-carboxylate

sodium tert-butoxide

toluene

→

tert-butyl (3R)-4-(5-fluoro-6-methylpyridin-2-yl)-3-methylpiperazine-1-carboxylate

Ausbeute 95.8%

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturAfter cooling to room temperature
2. 2
   Extraktionextracted with ethyl acetate
3. 3
   WaschenThe organic layer was washed with saturated brine
4. 4
   Trocknendried over anhydrous magnesium sulfate
5. 5
   SonstigeThe solvent was evaporated under reduced pressure
6. 6
   Sonstigethe residue was purified by silica gel column chromatography (n-hexane/ethyl acetate)

Vorschrift

To a mixture of 500 mg of 6-bromo-3-fluoro-2-methylpyridine, 580 mg of tert-butyl (3R)-3-methylpiperazine-1-carboxylate, 506 mg of sodium tert-butoxide, and 61 mg of 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene and 7.5 mL of toluene was added 48 mg of tris(dibenzylidenacetone)dipalladium (0), followed by stirring at 110° C. for 3 hours. After cooling to room temperature, the reaction mixture was poured into water and extracted with ethyl acetate. The organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure and the residue was purified by silica gel column chromatography (n-hexane/ethyl acetate) to obtain 780 mg of tert-butyl (3R)-4-(5-fluoro-6-methylpyridin-2-yl)-3-methylpiperazine-1-carboxylate.

Quelle