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

Participants

Reaction Conditions

Reaction Steps

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 vacuum. 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.

Provenance & Evidence