反应详情

A mixture of compound 47 (6.0 g, 20.27 mmol), 5-chloropyrazine-2-carboxylic acid methyl ester (5.3 g, 30.30 mmol), Et3N (6.2 g, 60.60 mmol) and dioxane (100 mL) is heated to reflux overnight. Solvent is removed. Saturated NH4Cl solution is added and extracted with EtOAc. The organic layer is concentrated to afford the crude product that is purified by chromatography on silica gel (EtOAc/heptane: 50%˜100%) to give the title compound (6.6 g, 76%) as a yellow solid.

1. temperatureis heated
2. temperatureto reflux overnight
3. customSolvent is removed
4. additionSaturated NH4Cl solution is added
5. extractionextracted with EtOAc
6. concentrationThe organic layer is concentrated
7. customto afford the crude product that
8. customis purified by chromatography on silica gel (EtOAc/heptane: 50%˜100%)