反应详情

Sodium hydroxide (24 mL, 24 mmol, 1N in water) was added to an ethanol (50 mL) solution of ethyl 2-(3-(3,4-dichlorobenzyl)ureido)thiazole-4-carboxylate (Example 38) (1.8 g, 4.8 mmol). The mixture was stirred overnight. The ethanol was removed by evaporation and the aqueous solution was filtered then the filter was washed with water (20 ml). The pH of the filtrate was adjusted to less than three with concentrated HCl. The precipitate was filtered, washed with water and dried to afford 2-(3-(3,4-dichlorobenzyl)ureido)thiazole-4-carboxylic acid.

1. customThe ethanol was removed by evaporation
2. filtrationthe aqueous solution was filtered
3. washthe filter was washed with water (20 ml)
4. filtrationThe precipitate was filtered
5. washwashed with water
6. customdried