3-Bromo-7-benzothiophene-carbaldehyde → 1-Benzothiophene-7-carbaldehyde

Participants

Reaction Steps

2 g of 5% palladium-on carbon catalyst are added to a solution of 10.4 g (43.15 mmoles) of 3-bromo-7-benzothiophene-carbaldehyde in 130 ml of tetrahydrofuran and 5.6 ml of triethylamine and the mixture is hydrogenated with hydrogen in a hydrogenating apparatus for 45 hours at 20°-22° C. under atmospheric pressure. The catalyst is then filtered off and the solvent is evaporated in vacuo from the filtrate. The residue is dissolved with 50 ml each of water and ethyl acetate, and 5.2 g (67.5% of the theoretical amount) of 7-benzothiophene-carbaldehyde are obtainable as residue from the separated organic phase after evaporation of the solvent in vacuo.

Provenance & Evidence