反应详情

温度

100 °C

Ethyl 4-hydroxy-2-methylbenzofuran-6-carboxylate (I-1c: 2.25 g, 10.22 mmol), potassium carbonate (2.1 g, 15.3 mmol), 5-chloro-N-ethyl-N-methylpyrazine-2-carboxamide (SM-4: 2.04 g, 10.2 mmol) were mixed in acetonitrile (30 ml). The mixture was heated at 100° C. over night, after which time, the reaction mixture was diluted with ethylacetate (50 ml) and filtered. The organic layer was concentrated and purified by column chromatography on silica gel eluting with ethylacetate in heptanes 20-100% to afford ethyl 4-(5-(ethyl(methyl)carbamoyl)pyrazin-2-yloxy)-2-methylbenzofuran-6-carboxylate (I-7a: (3.9 g, 99.5%) as a gum.

1. filtrationfiltered
2. concentrationThe organic layer was concentrated
3. custompurified by column chromatography on silica gel eluting with ethylacetate in heptanes 20-100%