Hydrogen Peroxide → 2,3,5-Trimethyl-1-oxidopyridin-1-ium

Temperature

90 °C

To a 100 liters reaction vessel was added 2,3,5-trimethyl-pyridine (10.9 kg, 89.2 moles) and acetic acid (30 liters). The temperature was raised to 90° C. The mixture was stirred for 3 hours and thereafter cooled to 60° C., whereafter H2O2 (35% solution, 3122 ml, 35.67 moles) was added during 1 hour. The temperature was then raised to 90° C. The reaction mixture was stirred overnight. After cooling to 40° C. an additional amount of H2O2 solution (936 ml, 10.7 moles) was added during 1 hour. The temperature was then raised to 90° C. The reaction mixture was stirred for 3 hours and was allowed to stand without heating overnight. Excess of acetic acid was distilled off under vaccum. To the remainder was added NaOH (10M) until pH 10. CH2Cl2 (10 liters) was added and the resulting mixture was stirred vigorously. The CH2Cl2 phase was separated and the water phase was extracted twice with CH2Cl2 (10 liters). The combined CH2Cl2 -phases were dried over MgSO4 and filtrated. The filtrate was evaporated yielding 2,3,5-trimethyl-pyridine-N-oxide (11920 g, 94% purity). The identity of the product was confirmed with 1H and 13C NMR.

1. customTo a 100 liters reaction vessel
2. additionwas added during 1 hour
3. temperatureThe temperature was then raised to 90° C
4. stirringThe reaction mixture was stirred overnight
5. additionwas added during 1 hour
6. temperatureThe temperature was then raised to 90° C
7. stirringThe reaction mixture was stirred for 3 hours
8. temperaturewithout heating overnight
9. distillationExcess of acetic acid was distilled off under vaccum
10. additionTo the remainder was added NaOH (10M) until pH 10
11. additionCH2Cl2 (10 liters) was added
12. stirringthe resulting mixture was stirred vigorously
13. customThe CH2Cl2 phase was separated
14. extractionthe water phase was extracted twice with CH2Cl2 (10 liters)
15. dry with materialThe combined CH2Cl2 -phases were dried over MgSO4
16. filtrationfiltrated
17. customThe filtrate was evaporated

ORD record

ord-5dfc6b339ef04ccfa6b2cd97d307d11f

Source dataset

uspto-grants-1986_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04620008