Hydrogen Peroxide → Piperonal

Temperature

94.5 °C

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).

1. customIn a glass-made reaction vessel equipped with a thermometer
2. temperaturewhile maintaining the pH of the reaction mixture to 5.5 to 6.5
3. customAfter completion of the reaction
4. customthe resulting reaction mixture
5. temperaturewas cooled to room temperature
6. customthe organic layer was separated as a solution
7. washThe resulting organic layer solution was washed with 80 mL of 1 mol/L aqueous sodium hydroxide solution
8. distillationthe solvent, xylene was distilled off with (1.3 kPa/132° C.)

ORD record

ord-45085ae4e397443f852fe60d9ebb6c09

Source dataset

uspto-grants-2013_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08618335B2