반응 #62875

반응 방정식

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

수율 45.0%

용매

sulpholane

반응 조건

후처리

1. 1
   온도After cooling to the ambient temperature (ca. 22° C.)
2. 2
   추출extracted into ethyl acetate
3. 3
   세척The organic layer was washed with water and brine
4. 4
   기타dried
5. 5
   기타the solvent evaporated under reduced pressure
6. 6
   기타The residual brown liquid was purified by column chromatography on silica gel

실험 절차

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.

출처