Thionyl Chloride → 1-Indanone, 4-bromo-

Participants

Reaction Steps

3-(2-Bromophenyl)propanoic acid (1) (550 g, 2.4 mol, 1 equiv) was dissolved in 1,2-dichloroethane (5.5 L). Thionyl chloride (437.8 mL, 6 mol, 2.5 equiv) was added to the solution and the mixture was refluxed for 24 hours. The reaction was cooled to room temperature and concentrated under reduced pressure. The residue was dissolved in methylene chloride (1 L) and added dropwise to a mechanically stirred suspension of anhydrous aluminum chloride (526.9 g, 3.96 mol, 1.65 equiv) in dichloromethane (1 L) while keeping the reaction temperature below 27° C. The reaction was stirred at room temperature for three hours before being quenched into a five gallon bucket which was half-full of ice. The resulting mixture was extracted with dichloromethane (3×3 L). The combined organic layers were washed sequentially with saturated brine (2 L) and saturated sodium bicarbonate (2 L). The organic layer was dried over sodium sulfate, and concentrated under reduced pressure. The resulting solid was dried overnight in a vacuum oven at 30° C. to give compound 2 (435 g, 86% yield) as an off-white solid.

Provenance & Evidence