4,5-Dibromo-3-methylthiophene-2-carboxylic acid

Подготовка

4,5-Dibromo-3-methyl-2-thiophenecarboxylic acid synthesis: 4,5-dibromo-3-methyl-2-thiophenecarbonitrile (26.2 g, 92.2 mmol), EtOH (175 mL), water (175 mL), and NaOH (18.6 g, 466 mmol) were stirred together at 80°C for 1 h. The solvent was removed, the solids were collected by filtration, dissolved in water, and washed with CH2Cl2. The water layer was acidified with 37% HCl, the white solid was collected by filtration and dried under vacuum at 60°C to give 25.9 g (94% wt.) of 4,5-dibromo-3-methyl-2-thiophenecarboxylic acid: m.p. 225-226°C; 1H NMR (CDCl3) 2.5 (s).