(E)-3-(benzo[b]thienyl)-2-propenoic acid ethyl ester → Benzo[b]thiophene-2-propanoic acid ethyl ester

Participants

Reaction Steps

A mixture of (E)-3-(benzo[b]thienyl)-2-propenoic acid ethyl ester (3.65 g, 15.7 mmol), absolute EtOH (200 mL) and 5% Pd/C (800 mg) was hydrogenated at 1 atm for 3 h. An additional 200 mg of 5% Pd/C was added and the mixture was again hydrogenated for 1.5 h. The mixture was filtered through a pad of Celite washing thoroughly with CH2Cl2. The combined filtrates were concentrated to dryness and the resulting glass was purified by flash chromatography, eluting with 15% EtOAc/hexane to give benzo[b]thiophene-2-propanoic acid ethyl ester (3.55 g, 15.2 mmol) in 96.5% as a glass.

Provenance & Evidence