Bromine → 4-Bromo-2-propionylthiophene

Participants

Reaction Steps

A 47.3 g (338 mmol) sample of 1-(2-thienyl)-1-propanone (Aldrich) was dissolved in 225 mL of CHCl3 and 101.3 g (760 mmol) of AlCl3 was added with stirring. To this mixture was added a solution of bromine (57.5 g, 360 mmol) in 375 mL of CHCl3. The mixture was stirred at room temperature over night then poured into 500 mL of ice water. The organic layer was separated, washed with water (2×200 mL), dried over MgSO4, filtered and evaporated to yield 81 g of the crude title compound, which was taken directly to the next step. mp 40°-41° C.; MS: 158 (M+H)+, 236 (M+NH4)+ ; NMR (CDCl3) δ: 1.22 (t, 3H, J=7.5 Hz), 2.91 (q, 2H, J=7.5Hz), 7.51 (d, 1H), 7.60 (d, 1H). IR (KBr): 2960, 1670, 1400, 1220 cm-1.

Provenance & Evidence