反应详情

A mixture of 29 g of 2-methyl-5-thiazolecarboxaldehyde, 30 ml of pyridine, 29 g of malonic acid and 30 drops of pyridine was heated at 100°-110° C. for 5 hours and after cooling to room temperature, the mixture was poured into 500 ml of water. The pH of the solution was adjusted to 3 by addition of N sulfuric acid and the precipitate formed was recovered by vacuum filtration and was dried to obtain 27.8 g of 3-(2-methyl-5-thiazolyl)-2-propenoic acid which were crystallized from 10% aqueous ethanol to obtain 23.8 g of the said product melting at 204° C.

1. temperaturewas heated at 100°-110° C. for 5 hours
2. customthe precipitate formed
3. filtrationwas recovered by vacuum filtration
4. customwas dried