Hydrochloric Acid → HCID 20377688, compound

Participants

Reaction Steps

2-{3-(5-Carboxy-thieno[2,3-b]thien-2-yl)carbonyl-phenyl}butyric acid (15.6 g) and copper powder (1 g) are suspended in quinoline (150 cc) and heated at 195°-200° C. for 20 minutes, and then at the boil for 10 minutes. After cooling, ice (300 g) and a 12 N concentrated aqueous solution of hydrogen chloride (100 cc) are added to the reaction mixture, which is extracted three times with methylene chloride (total 600 cc). The combined methylene chloride solutions are washed three times with distilled water (total 300 cc), and then extracted twice with a 2 N aqueous solution of sodium hydroxide (total 400 cc) and three times with distilled water (total 600 cc). The combined aqueous alkaline phases are acidified to pH 1 by the addition of a 12 N concentrated aqueous solution of hydrogen chloride and extracted three times with methylene chloride (total 450 cc). The combined methylene chloride solutions are washed three times with distilled water (total 300 cc), dried over anhydrous sodium sulphate in the presence of decolourizing charcoal (5 g), filtered and evaporated. The residue obtained (9.3 g) is dissolved in boiling acetonitrile (70 cc). After cooling, starting the crystallization and standing for one hour at 4° C., the resulting crystals are filtered off, washed once with iced acetonitrile (15 cc) and dried under reduced pressure (20 mm Hg) at a temperature of about 20° C., in the presence of potassium hydroxide pellets. Crude 2-{3-(thieno[2,3-b]thien-2-yl)carbonyl-phenyl}butyric acid (7.8 g), melting at 143° C., is thus obtained.

Provenance & Evidence