反应详情

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.

1. temperaturewas heated
2. temperatureto reflux
3. customwhile removing moisture
4. additionthe mixture was charged with potassium hydroxide (0.58 kg) over 3 hours and 45 minutes
5. temperatureThe reaction system was cooled to 30° C. or less
6. additioncharged with ethyl acetate (2.5 L) and 17% saline solution (3.5 L)
7. waitThe resultant solution was left
8. waitto stand overnight
9. customThe ethyl acetate layer was collected
10. extractionthe aqueous layer was extracted with ethyl acetate (1.0 L×3)
11. filtrationThe combined ethyl acetate layers were filtered with Celite
12. concentrationconcentrated under reduced pressure