反应详情

A mixture of 2,3-diamino-5-bromopyridine (2.5 g, 13.31 mmol) and ethyl 2-chloroacetoacetate (2.41 g, 14.64 mmol) in 35 ml abs. Ethanol was refluxed for 14 h. The ethanol was evaporated under reduced pressure. The residue was dissolved in methylene chloride and neutralized by aqueous NaHCO3. The organic layer was separated, dried and evaporated in vacuo. The residue was purified by column chromatography on silica gel with methylene chloride:methanol (100:3.5) as eluent to give 1.55 g (39%) of the title compound.

1. customThe ethanol was evaporated under reduced pressure
2. dissolutionThe residue was dissolved in methylene chloride
3. customThe organic layer was separated
4. customdried
5. customevaporated in vacuo
6. customThe residue was purified by column chromatography on silica gel with methylene chloride:methanol (100:3.5) as eluent