反应详情

A mixture of 2,2,2-trifluorethanol (6.9 ml, 96 mmol) and cesium carbonate (1.56 g, 4.8 mmol) was stirred for 20 min, 3-amino-5-chloro-pyrazine-2-carboxylic acid methyl ester (600 mg, 3.2 mmol; GB 1248146) was added and the mixture was stirred at rt for 42 h. To complete the reaction the mixture was heated to reflux for another 3 h. Saturated aq. NH4Cl was added and the mixture was extracted with EtOAc, the combined organic layers were washed with saturated aq. sodium chloride, dried with Na2SO4 and evaporated. The residue was purified by chromatography on silica gel (cyclohexane to cyclohexane/EtOAc 3:7) to provide the title compound as colorless solid.

1. stirringthe mixture was stirred at rt for 42 h
2. customthe reaction the mixture
3. temperaturewas heated
4. temperatureto reflux for another 3 h
5. extractionthe mixture was extracted with EtOAc
6. washthe combined organic layers were washed with saturated aq. sodium chloride
7. dry with materialdried with Na2SO4
8. customevaporated
9. customThe residue was purified by chromatography on silica gel (cyclohexane to cyclohexane/EtOAc 3:7)