Thionyl Chloride → 2-Chloro-6-(chloromethyl)pyridine

To a mixture of (6-chloro-pyridine-2-yl)-methanol (200 mg, 1.39 mmol) described in Manufacturing Example 52-1-1 and toluene (3 mL) was added thionyl chloride (152 μL, 2.09 mmol) on an ice bath, which was stirred for 2 hours at room temperature. Saturated aqueous sodium hydrogencarbonate solution was added to the reaction mixture, which was then extracted with ethyl acetate. The organic layer was separated, washed with water and saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate, and filtered. The filtrate was concentrated under a reduced pressure, and the residue was purified by NH silica gel column chromatography (heptane:ethyl acetate=4:1) to obtain the title compound (163.2 mg, 73%).