反应详情

A reaction mixture was prepared containing 15.5 g of dimethylaminothioacetamide hydrochloride, 20.5 g. of ethyl bromopyruvate and 100 ml. of ethanol. The reaction mixture was heated to refluxing temperature for about four hours after which time the solvent was removed in vacuo in a rotary evaporator. The residue, containing ethyl 2-(dimethylaminomethyl)-4-thiazolecarboxylate formed in the above reaction, was dissolved in a mixture of ether and water. The aqueous layer was separated. The ether layer was extracted with an equal volume of water and then discarded. The two aqueous layers were combined and washed with ether. The ether layer was again discarded and the aqueous layer cooled to a temperature in the range of 0°-5° C. Solid potassium carbonate was added until the aqueous layer gave a basic reaction to litmus. An oil separated comprising ethyl 2-(dimethylaminomethyl)-4-thiazolecarboxylate free base. The oily layer was extracted with ether and the ether extract separated and dried. The ether was removed by evaporation in vacuo. The resulting residue was purified by gradient high pressure liquid chromatography over silica using a toluene-ethyl acetate eluant. Ethyl 2 -(dimethylaminomethyl)-4-thiazolecarboxylate thus obtained had the following physical characteristics:

1. customA reaction mixture was prepared
2. temperatureThe reaction mixture was heated
3. temperatureto refluxing temperature for about four hours after which time the solvent
4. customwas removed in vacuo in a rotary evaporator
5. additionThe residue, containing ethyl 2-(dimethylaminomethyl)-4-thiazolecarboxylate
6. customformed in the above reaction
7. customThe aqueous layer was separated
8. extractionThe ether layer was extracted with an equal volume of water
9. washwashed with ether
10. temperaturethe aqueous layer cooled to a temperature in the range of 0°-5° C
11. additionSolid potassium carbonate was added until the aqueous layer
12. customgave
13. customa basic reaction to litmus
14. customAn oil separated
15. extractionThe oily layer was extracted with ether
16. extractionthe ether extract
17. customseparated
18. customdried
19. customThe ether was removed by evaporation in vacuo
20. customThe resulting residue was purified by gradient high pressure liquid chromatography over silica using a toluene-ethyl acetate eluant