反应详情

In 25 ml of methanol was dissolved 1.2 g of 2-chloro-3,4-diethoxycarbonyl-5-nitro-6-phenylpyridine as obtained in Reference Example 18. To the solution was added 6.34 ml (2.0 eq.) of a solution of 1N sodium methoxide in methanol, and the mixture was stirred at room temperature for 30 minutes. The reaction mixture was neutralized with 0.2 ml (1.1 eq.) of acetic acid, and the solvent was distilled off. Water was added to the residue, and the mixture was extracted with ethyl acetate. The organic layer was washed with water and a saturated aqueous solution of sodium chloride and dried. The solvent was distilled off. The residue was purified by silica gel column chromatography (eluent:ethyl acetate). The resulting crystals were collected by filtration with hexane.

1. customas obtained in Reference Example 18
2. distillationthe solvent was distilled off
3. additionWater was added to the residue
4. extractionthe mixture was extracted with ethyl acetate
5. washThe organic layer was washed with water
6. dry with materiala saturated aqueous solution of sodium chloride and dried
7. distillationThe solvent was distilled off
8. customThe residue was purified by silica gel column chromatography (eluent:ethyl acetate)
9. filtrationThe resulting crystals were collected by filtration with hexane