To a dry reaction tube were sequentially added 0.2 mmol 1-(4-chlorophenyl)cyclobutanol, 0.02 mmol manganese dichloride (MnCl2), 0.6 mmol trimethylsilyl chloride (TMSCl), 0.4 mmol 2-iodobenzoic acid and 1 mL acetonitrile (MeCN). The reaction mixture was stirred at 50°C for 7 hours. After completion of the reaction, the solvent was removed by distillation under reduced pressure. The crude product was purified by column chromatography using a solvent mixture of petroleum ether and ethyl acetate as eluent (20:1 v/v). The final product was 4,4'-dichlorobutyrophenone in 88.2% yield and 98% purity.
