Hydrochloric Acid → 5-Bromo-3-(2-chloro-ethyl)-thiophene-2-carbonyl chloride

Participants

Reaction Steps

A mixture of 2-Bromo-4,5-dihydro-thieno[2,3-c]pyran-7-one (400 mg), Lithium hydroxide (246.7 mg) in THF/water/methanol (1.7 mL/1.7 mL/0.2 mL) was stirred for 6 h at room temperature. Then the reaction mixture was acidified with 2 N HCl and the aqueous phase was extracted with ethyl acetate, dried over sodium sulfate and the solvent removed. The obtained crude product was heated to reflux with thionylchloride (6.2 mL) for 2 h. Toluene was added and the volatile components removed in vacuum. This step was repeated twice.

Provenance & Evidence