反应详情

Alternatively, a mixture of 2.14 g of ethyl 2-dimethylaminomethyl-4-thiazolecarboxylate and 0.38 g of sodium borohydride in 20 ml. of isopropanol was heated with stirring at reflux temperature for about 14 hours. The reaction mixture was cooled, and 2 ml. of water were added carefully followed by 4 ml. of 5N aqueous hydrochloric acid. The volatile constituents were removed by evaporation. Methanol (10 ml.) was added and the mixture heated to refluxing temperature for about one hour. Methanol was removed by evaporation and the residual solids digested in 10 ml. of isopropanol on the steam bath. The isopropanol solution was separated by decantation and the solids reextracted with 10 m. of isopropanol. The isopropanol solutions and extracts were combined and the combined solution filtered while hot to remove insoluble material. The filtrate was chilled and a crystalline solid appeared which separated and was recovered by filtration. Recrystallization of the filter cake from isopropanol gave 1.73 g of 2-dimethylaminomethyl-4-thiazolemethanol hydrochloride melting at 153°-154° C.

1. temperatureat reflux temperature for about 14 hours
2. temperatureThe reaction mixture was cooled
3. customThe volatile constituents were removed by evaporation
4. additionMethanol (10 ml.) was added
5. temperaturethe mixture heated
6. temperatureto refluxing temperature for about one hour
7. customMethanol was removed by evaporation
8. customThe isopropanol solution was separated by decantation
9. filtrationthe combined solution filtered while hot
10. customto remove insoluble material
11. temperatureThe filtrate was chilled
12. customseparated
13. filtrationwas recovered by filtration
14. customRecrystallization of the filter cake from isopropanol