Methanol → 3-Hydroxy-5-(trifluoromethyl)thiophene-2-carboxylic acid

Beteiligte Stoffe

Reaktionsschritte

A mixture of 5B (2.38 g) and methanol (20 ml) was added to a stirred solution of sodium hydroxide (1.68 g) in water (20 ml). The reaction mixture was heated at reflux for 3 hours. The reaction mixture was cooled to room temperature and concentrated in vacuo. The concentrate was cooled to 5° C. and acidified with concentrated HCl (3.5 ml). The resulting suspension was stirred at 5° C. for 30 minutes. The solid was collected by filtration, washed with water, then dried in vacuo at 35-40° C. to give the free acid (1.45 g, 65%).

Herkunft & Nachweise