A mixture of 6-hydroxy-2-(1-methyl-3-trifluoromethylpyrazol-5-yloxy)-4-methylpyridine (0.9 g, 3.3 mmol) and NaH (60% in oil, 0.16 g, 4 mmol) in acetonitrile (20 ml) and DMF (1 ml) is stirred for 10 min at ambient temperature and (E)-1,3-dichloropropene (0.4 g, 3.6 mmol) is added. After stirring for 60 h at ambient temperature, the remaining NaH is deactivated and the resulting mixture is diluted with pentane/ethyl acetate (by volume ration 1/1) and filtered through a bed of silica gel. The filtrate is washed with water. The organic layer is dried with anhydrous magnesium sulfate, filtered and evaporated in vacuo. Purification by flash chromatography (silica gel: pentane/ethyl acetate 9/1 v/v) yields the title compound (0.6 g, 52% yield) as an colorless oil.
