反应详情

2-(3,4-Dimethoxyphenyl)-3-pyridinol (10.0 g, 43.2 mmoles, described in Example 3) is dissolved in p-dioxane (60 ml) containing 0.1 ml of 12.5N sodium hydroxide. The solution is hydrogenated for 17 hours with Raney nickel catalyst (1.5 g) at 1750 p.s.i. and 140° C. The mixture is filtered and the filtrate is evaporated. The residue is subjected to chromatography on alumina (Woelm, basic activity I) using first chloroform as eluant and then a 1:10 methanol-chloroform solvent combination. The eluates are evaporated, dissolved in acetone and maleic acid is added. The precipitate is crystallized from isopropanol-hexane to give the title compound as the maleate salt, mp 180°-181° C.

1. custom140° C
2. filtrationThe mixture is filtered
3. customthe filtrate is evaporated
4. customThe eluates are evaporated
5. dissolutiondissolved in acetone
6. additionmaleic acid is added
7. customThe precipitate is crystallized from isopropanol-hexane