141-75-3

108-95-2

1009-11-6

General method: phenol (0.28 mmol) and n-butyryl chloride (0.28 mmol) were dissolved in trifluoromethanesulfonic acid (TfOH, 3 mL) at 0°C. The reaction mixture was gradually warmed up to room temperature and the reaction was carried out for the time shown in Table 2. Upon completion of the reaction, the mixture was poured into a mixture of cold water and ethyl acetate. The organic layer was separated and washed sequentially with 1 M hydrochloric acid, saturated sodium bicarbonate solution and saturated sodium chloride solution. The organic layer was dried with anhydrous magnesium sulfate, filtered and the filtrate concentrated. The residue was purified by silica gel column chromatography to give 4'-hydroxybutyrophenone. The spectral data of all the products were in agreement with those reported in the literature.