反应详情

温度

40 °C

A mixture of 5-(4-ethylphenoxy)-2-(mercapto)pyrimidine-4(3H)-one (2.49 g, 10.28 mmoles), ethanol (250 mL) and wet Raney Ni (50% slurry in water, active catalyst) (Aldrich) (10.9 g) was refluxed with stirring for 3 hours. The reaction was cooled to about 40° C. and filtered through a pad of Celite 545 (Fisher). The pad was washed with hot ethanol (2×75 mL), and the pad was placed in a beaker of water. The combined filtrates were spin evaporated in vacuo to a syrup. The syrup was dissolved in ethyl acetate and reevaporated to give a gray solid. The solid was dissolved in ethyl acetate (40 mL) and applied to a column (4.2×9.5.cm) of Silica Gel 60 (E.M. Science, 230-440 mesh) that was equilibrated with ethyl acetate. The column was eluted with ethyl acetate by flash chromatography, and twelve 100 mL fractions were collected. Fractions 4-10 were combined and spin evaporated in vacuo. The residual oil was dissolved in ethyl acetate and evaporated to give a mixture of light green and white crystals. The crystals were dissolved in dichloromethane and spin evaporated in vacuo to give 1.37 g (63% yield) of 5-(4-ethylphenoxy)pyrimidine-4(3H)-one. Recrystallization of a sample form ethyl acetate gave analytically pure 5-(4-ethylphenoxy)-2-(mercapto)pyrimidine-4(3H)-one as white needles, mp 144-146° C.

1. temperaturewas refluxed
2. filtrationfiltered through a pad of Celite 545 (Fisher)
3. washThe pad was washed with hot ethanol (2×75 mL)
4. customThe combined filtrates were spin evaporated in vacuo to a syrup
5. dissolutionThe syrup was dissolved in ethyl acetate
6. customreevaporated
7. customto give a gray solid
8. washThe column was eluted with ethyl acetate by flash chromatography, and twelve 100 mL fractions
9. customwere collected
10. customspin evaporated in vacuo
11. dissolutionThe residual oil was dissolved in ethyl acetate
12. customevaporated
13. customto give
14. additiona mixture of light green and white crystals
15. customspin evaporated in vacuo