Sodium Chloride → Methyl 2,6-dichloro-5-methoxypyrimidine-4-carboxylate

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The 2,6-dichloro-5-methoxy-pyrimidine-4-carbaldehyde crude material (32.5 mmol), prepared by Example 7, was cooled to 0° C. in an ice/water bath. It was assumed that approximately 60 mL of methanol was still present in the crude material. Additional methanol (60 mL) and water (13 mL) was added to the chilled crude material. Solid sodium bicarbonate (54.7 g) was added, and the solution stirred vigorously. A 2 M solution of bromine (81.4 mL, 163 mmol) in methanol and water (9:1) was dropwise added to the crude material solution over 30 minutes. The reacting mixture was stirred at 0° C. for 1 h. The mixture was then removed from the ice/water bath, and the reaction monitored using GCMS. About 6 h after initiating the reaction with bromine, a mixture of Na2S2O3.5H2O (4.5 g), saturated NaCl (150 mL), and ice (400 g) was prepared and, into this, the reaction mixture was poured. This was diluted with ethyl acetate (200 mL), and additional ethyl acetate (200 mL) was used to extract the product. The combined organic phases were dried over sodium sulfate, filtered, and toluene (50 mL) was then added. The product was then concentrated on a rotary evaporator with a bath temperature of less than or equal to 25° C. Obtained was a yellow oil comprising the title compound (3.1 g, 45% yield). The title compound was not isolated from the solution.

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