Hydrogen Peroxide → Piperonal

Participants

Reaction Conditions

Reaction Steps

In a glass-made reaction vessel equipped with a thermometer, a temperature controller, a dropping device and a stirring device were charged 220 ml of xylene, 76.01 g (500 mmol) of piperonyl alcohol, 1.65 g (5.0 mmol) of sodium tungstate.dihydrate (Na2WO4.2H2O), 1.70 g (5.0 mmol) of tetrabutyl ammonium hydrogen sulfate and 9.42 g of water. Then, to the mixture were added 2.34 g (1.6 mmol) of sodium dihydrogen phosphate.dihydrate and 3.56 g (1.0 mmol) of disodium hydrogen phosphate.1 dihydrate, and a pH of the reaction mixture was adjusted to pH 6.0. Next, an inner temperature of the reaction mixture was maintained from 94 to 95° C., 48.0 ml (991 mmol) of 60% aqueous hydrogen peroxide was added dropwise to the mixture with 141 mmol/hr, while maintaining the pH of the reaction mixture to 5.5 to 6.5 by using 8 mol/L aqueous sodium hydroxide solution. After completion of the reaction, the resulting reaction mixture was cooled to room temperature, and the organic layer was separated as a solution. The resulting organic layer solution was washed with 80 mL of 1 mol/L aqueous sodium hydroxide solution, and the solvent, xylene was distilled off with (1.3 kPa/132° C.) to obtain 67.7 g of piperonal as white solid (yield: 89.3%, based on piperonyl alcohol).

Provenance & Evidence