Phenylglyoxal monohydrate

98-86-2

1075-06-5

GENERAL METHOD: Selenium dioxide (220 mg, 2 mmol) was dissolved in a mixed solution of 1,4-dioxane (1 mL) and deionized water (2 drops), followed by the addition of acetophenone 1a (120 mg, 1 mmol). The reaction mixture was refluxed with stirring for 7 h (the reaction progress was monitored by TLC, the unfolding agent was ethyl acetate/petroleum ether, 1:4, v/v). After completion of the reaction, it was cooled to room temperature, dichloromethane (5 mL) was added to the mixture and filtered through diatomaceous earth. The diatomaceous earth was washed with dichloromethane (3 x 5 mL). All organic phases were combined and concentrated under reduced pressure. The residue was purified by silica gel column chromatography with the eluent ethyl acetate/petroleum ether (1:10 v/v) to give benzoylformaldehyde hydrate 2a (121 mg, 80% yield). Compounds 2b~2m were synthesized following the same procedure in a range of 61%~82% yield.