反应详情

9.2 g of 4-(6carboxyhexyl)-thiazole-5-carboxylic acid (IX, R1 = H) and 10.2 g of p-toluenesulphonic acid monohydrate were dissolved in 400 ml of methanol. The obtained reaction mixture was stirred for 2 hours at room temperature, then poured onto one liter of water. After saturating the aqueous solution with ammonium sulphate it was extracted with 3 × 400 ml of ethyl acetate, then the ethyl acetate extract was washed with water, dried over sodium sulphate and evaporated in vacuo. Recrystallization of the obtained crude product from a mixture of diethyl ether and n-hexane afforded 7.9 of 4-(6-carbomethoxyhexyl)-thiazole-5-carboxylic acid (X, R1 = H). M.p.: 113°-114° C.

1. customThe obtained reaction mixture
2. concentrationAfter saturating the aqueous solution with ammonium sulphate it
3. extractionwas extracted with 3 × 400 ml of ethyl acetate
4. extractionthe ethyl acetate extract
5. washwas washed with water
6. dry with materialdried over sodium sulphate
7. customevaporated in vacuo
8. customRecrystallization of the
9. customobtained crude product