反应详情

To a suspension of lithium aluminum hydride (0.5 g) in dry tetrahydrofuran (260 ml) is portionwise added 2-guanidino-4-ethoxycarbonylthiazole (3.6 g) at 0° C. with stirring in half an hour, and the resultant mixture is refluxed under stirring for 4 hours. Ethyl acetate and water are added to the reaction mixture for decomposing excess lithium aluminum hydride. The organic layer is separated and the residual layer is extracted with methanol. The methanolic extract is combined with the organic layer, dried over anhydrous sodium sulfate and concentrated in vacuum. The residue is chromatographed on a column of silica gel, which is eluted with ethyl acetate:methanol (4:1, v/v). The eluate is concentrated in vacuum to give 2-guanidino-4-hydroxymethylthiazole (1.8 g) as crystals melting at 163°-165° C. The yield is 62.2%.

1. customat 0° C.
2. stirringunder stirring for 4 hours
3. customThe organic layer is separated
4. extractionthe residual layer is extracted with methanol
5. extractionThe methanolic extract
6. dry with materialdried over anhydrous sodium sulfate
7. concentrationconcentrated in vacuum
8. customThe residue is chromatographed on a column of silica gel, which
9. washis eluted with ethyl acetate:methanol (4:1
10. concentrationThe eluate is concentrated in vacuum