反应详情

To a solution of a whole amount of 2-methylsulfinyl-4-(3-chloro-4-methoxybenzylamino)-5-ethoxycarbonylpyrimidine (prepared in Example 68-(1)) in tetrahydrofuran 6 ml is dropped 2N aqueous sodium hydroxide solution 1.32 ml under ice cooling over a 2 minite period and the reaction mixture is stirred at the same temperature for 30 minutes. Further tetrahydrofuran 8 ml and N,N-dimethylacetamide 6 ml are added thereto and the mixture is stirred under ice cooling for 30 minites. Thereto are added water 5 ml and N,N-dimethylacetamide 2 ml and the mixture is stirred under ice cooling for one hour. The reaction mixture is acidified with an aqueous 10% citric acid solution and diluted with water, extracted twice with ethyl acetate. The combined organic layer is washed with water and an aqueous saturated sodium chloride solution, dried over anhydrous sodium sulfate and concentrated in vacuo. The residue is separated by silica gel chromatography (silica gel 20 g, solvent; chloroform:ethyl acetate=5:1→chloroform:isopropanol=30:1) to give 2-hydroxy-4-(3-chloro-4-methoxybenzylamino)-5-ethoxycarbonylpyrimidine as a slightly yellowish crystalline powder, 618 mg. mp 195–197° C.

1. stirringthe mixture is stirred under ice cooling for 30 minites
2. stirringthe mixture is stirred under ice cooling for one hour
3. extractionextracted twice with ethyl acetate
4. washThe combined organic layer is washed with water
5. dry with materialan aqueous saturated sodium chloride solution, dried over anhydrous sodium sulfate
6. concentrationconcentrated in vacuo
7. customThe residue is separated by silica gel chromatography (silica gel 20 g, solvent; chloroform:ethyl acetate=5:1→chloroform:isopropanol=30:1)