反应详情

温度

80 °C

A solution of potassium carbonate (691 g, 5 mol) in 1.5 l of water is treated with 1,3-propanedithiol (432.8 g, 4 mol) under a nitrogen atmosphere and heated to 80° C. A solution of (4-chloro-3-methylpyridin-2-yl)methanol hydrochloride (194.1 g, 1 mol) in 400 ml of water is then added dropwise at this temperature with vigorous stirring during the course of about 2 h. The mixture is additionally stirred at 80 to 85° C. for 18 h and then cooled to room temperature. After separating off the aqueous phase, the organic phase is treated with toluene (1.5 l) and washed with water (2×1 l). The organic phase is then extracted with 2M hydrochloric acid (2 l). The hydrochloric acid phase is concentrated and the residue is recrystallized from isopropanol. 159 g (60%) of the title compound are isolated. The crude product is employed without further purification for the synthesis of the compound of Example 1.

1. stirringThe mixture is additionally stirred at 80 to 85° C. for 18 h
2. temperaturecooled to room temperature
3. customAfter separating off the aqueous phase
4. additionthe organic phase is treated with toluene (1.5 l)
5. washwashed with water (2×1 l)
6. extractionThe organic phase is then extracted with 2M hydrochloric acid (2 l)
7. concentrationThe hydrochloric acid phase is concentrated
8. customthe residue is recrystallized from isopropanol