Reaktion #62875

Reaktionsgleichung

water

potassium fluoride

ethyl (RS)-2-[2-(2-methylprop-2-yl)-4-chloropyrimidin-5-yl]-3-methylbutyrate

18-crown-6

→

ethyl (RS)-2-[2-(2-methylprop-2-yl)-4-fluoropyrimidin-5-yl]-3-methylbutyrate

Ausbeute 45.0%

Lösungsmittel

sulpholane

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturAfter cooling to the ambient temperature (ca. 22° C.)
2. 2
   Extraktionextracted into ethyl acetate
3. 3
   WaschenThe organic layer was washed with water and brine
4. 4
   Sonstigedried
5. 5
   Sonstigethe solvent evaporated under reduced pressure
6. 6
   SonstigeThe residual brown liquid was purified by column chromatography on silica gel

Vorschrift

A stirred suspension of dry potassium fluoride (1.41 g) and ethyl (RS)-2-[2-(2-methylprop-2-yl)-4-chloropyrimidin-5-yl]-3-methylbutyrate (1.88 g) in dry sulpholane (14 cm3) in the presence of 18-crown-6 (0.38 g) was heated to 150° C. for a period of 24 hours, under an atmosphere of dry nitrogen. After cooling to the ambient temperature (ca. 22° C.), the reaction mixture was poured into water, and extracted into ethyl acetate. The organic layer was washed with water and brine, dried and the solvent evaporated under reduced pressure. The residual brown liquid was purified by column chromatography on silica gel, using dichloromethame as eluent, to give ethyl (RS)-2-[2-(2-methylprop-2-yl)-4-fluoropyrimidin-5-yl]-3-methylbutyrate (0.8 g) as an orange liquid.

Quelle