4-Chloro-2,3,5-trimethyl-1-oxidopyridin-1-ium → 4-((2,2-Dimethyl-1,3-dioxan-5-yl)methoxy)-2,3,5-trimethylpyridine 1-oxide

Participants

Reaction Steps

A mixture of 4-chloro-2,3,5-trimethylpyridine 1-oxide (840 g), (2,2-dimethyl-1,3-dioxan-5-yl)methanol (688 g) and toluene (2.52 L) was heated to reflux while removing moisture. While continuing the azeotropic dewatering, the mixture was charged with potassium hydroxide (0.58 kg) over 3 hours and 45 minutes, and the azeotropic dewatering was then continued for another 2.5 hours. The reaction system was cooled to 30° C. or less and then charged with ethyl acetate (2.5 L) and 17% saline solution (3.5 L). The resultant solution was left to stand overnight. The ethyl acetate layer was collected, and the aqueous layer was extracted with ethyl acetate (1.0 L×3). The combined ethyl acetate layers were filtered with Celite and then concentrated under reduced pressure to obtain 1.20 kg of the title compound.

Provenance & Evidence