Thioglycolic Acid → 6-Bromo-1-benzothiophene-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A stirred solution of 2-bromo-6-fluorobenzaldehyde (2.3 Kg, 11.33 moles) and mercaptoacetic acid (1.04 Kg, 11.33 mole) is added to a solution of KOH (951 g, 16.99 mol) in dimethylformamide (11.0 L) at room temperature. The reaction mixture is stirred for 1.5 h at 136 to 140° C. Upon completion of the reaction, the reaction mixture is cooled to 10° C. and quenched with concentrated HCl (2.5 L). The mixture is stirred for 1 h at 10° C. and the resulting solid is filtered. The filtered cake is washed with water (2×3 L) and dried under vacuum to afford the title compound (2.2 Kg, 76%) as a yellow solid.

Provenance & Evidence