反应详情

To a solution of 6-chloro-5-nitro-nicotinic acid ethyl ester (10.5 g, prepared from 6-hydroxy-nicotinic acid with a) fuming nitric acid, b) PCl5, POCl3, c) EtOH, see WO2005012288) in dioxan (100 ml) was added methylglycolate (4.92 g). Sodium hydride (55% dispersion in mineral oil, 2.19 g) was added portion wise at 0° C. The mixture was stirred at room temperature for 24 h. Water was added and the mixture was extracted with EtOAc. The organic phase was dried (MgSO4), filtered and concentrated to dryness. The product was purified by chromatography (SiO2, cyclohexane/EtOAc 1:0=>7:3) to give the title compound (3.026 g) as yellow oil. MS (m/e)=285.2 [M+H+].

1. extractionthe mixture was extracted with EtOAc
2. dry with materialThe organic phase was dried (MgSO4)
3. filtrationfiltered
4. concentrationconcentrated to dryness
5. customThe product was purified by chromatography (SiO2, cyclohexane/EtOAc 1:0=>7:3)