Water → 4-(6-Carbomethoxyhexyl)-thiazole-5-carboxylic acid

Participants

Reaction Steps

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.

Provenance & Evidence