Hydrochloric Acid → 6-Bromo-benzo[b]thiophene

Participants

Reaction Conditions

Reaction Steps

Copper powder (100 g, 1.57 mol) is added to a solution of 6-bromo-benzo[b]-thiophene-2-carboxylic acid (1.04 Kg, 4.04 mol) in quinoline (2.5 L) at room temperature. The reaction mixture is heated to reflux (195° C.) for 10 h. The reaction mixture is cooled to room temperature and poured onto ice (2.5 Kg). Concentrated HCl (2.5 L) is added while stirring the resulting mass for 1 h. The reaction mixture is extracted with hexane (4×3 L) and washed with dilute HCl (1×2 L), aqueous bicarbonate (1×5 L), and brine solution (1×5 L). The layers are separated and the organic layer is dried over sodium sulfate and concentrated to give the title compound (0.54 Kg, 62%) as a light yellow solid.

Provenance & Evidence