反应详情

To a well stirred mixture of 20 ml. of 12.5% phosgene in benzene and 50 ml. of benzene is added dropwise a solution of 2.5 gm. (0.01 moles) of 2-methyl-3-hydroxy-4-mercaptomethyl-5-vinylpyridine in 25 ml. of benzene. The reaction mixture is stirred for 3 hours and then purged with nitrogen for 1 hour to remove any unreacted phosgene. The reaction mixture is then concentrated in vacuo to give a gummy solid. To the above is added 5.6 gm. (0.04 moles) of ethyl glycinate and 100 ml. of dry dioxane. The mixture is stirred and 6 ml. of triethylamine added. After stirring overnight at room temperature, the mixture is concentrated in vacuo and the residue extracted between ether and saturated sodium bicarbonate solution. The ether layer is separated, washed with water, dried over sodium sulfate and concentrated to give crude product. Chromatography on 900 gm. of silica gel and elution with ether gives ethyl N-(2-methyl-3-hydroxy-5-vinyl-4-pyridylmethylthiocarbonyl)glycinate.

1. additionmixture of 20 ml
2. stirringThe reaction mixture is stirred for 3 hours
3. custompurged with nitrogen for 1 hour
4. customto remove any unreacted phosgene
5. concentrationThe reaction mixture is then concentrated in vacuo
6. customto give a gummy solid
7. additionTo the above is added 5.6 gm
8. stirringThe mixture is stirred
9. stirringAfter stirring overnight at room temperature
10. concentrationthe mixture is concentrated in vacuo
11. extractionthe residue extracted between ether and saturated sodium bicarbonate solution
12. customThe ether layer is separated
13. washwashed with water
14. dry with materialdried over sodium sulfate
15. concentrationconcentrated
16. customto give crude product
17. washof silica gel and elution with ether