Hydrogen Peroxide → 2-Propylpyridine 1-oxide

Temperature

75 °C

To a solution of 2-n-propylpyridine (187.4 g, 1.505 mol) in 900 ml of acetic acid was added 149 ml of 35% aqueous hydrogen peroxide and the mixture was stirred and heated to 70-80° C. After three hours a further 104 ml of the hydrogen peroxide solution was added, and the mixture was maintained at the same temperature for an additional nine hours. The mixture was concentrated to about 300 ml in volume, 300 ml of water was added, and the mixture was concentrated as far as possible. The residue was made alkaline with anhydrous sodium carbonate, shaken with 750 ml of dichloromethane, and allowed to stand overnight. The resulting deposit of sodium carbonate and sodium acetate was removed by filtration. The filtrate was dried over magnesium sulfate, the solvent removed, and the residue distilled under reduced pressure. This gave 176 g (81%) of 2-n-propylpyridine-N-oxide. B.p. 120-140° C./9-15 mbar. 1H-NMR (CDCl3, 200 MHz) δ: 1.05 (t, 3H); 1.80 (sext, 2H); 2.89 (t, 2H); 7.10-7.28 (m, 3H); 8.28 (d, 1H).

1. temperaturethe mixture was maintained at the same temperature for an additional nine hours
2. concentrationThe mixture was concentrated to about 300 ml in volume, 300 ml of water
3. additionwas added
4. concentrationthe mixture was concentrated as far as possible
5. stirringshaken with 750 ml of dichloromethane
6. customThe resulting deposit of sodium carbonate and sodium acetate was removed by filtration
7. dry with materialThe filtrate was dried over magnesium sulfate
8. customthe solvent removed
9. distillationthe residue distilled under reduced pressure

ORD record

ord-2a2798c216424b8c8cdcaead6a39de56

Source dataset

uspto-grants-2000_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06080754