1192064-63-3

75-16-1

5750-76-5

1192064-63-3

Intermediate 13: Synthesis of 2,5-dichloro-4-methylpyrimidine. To a THF/NMP (86 mL/6 mL) solution of 2,4,5-trichloropyrimidine (2.52 g, 13.74 mmol) was added Fe(acac)3 (485 mg, 1.37 mmol) and the mixture was cooled to 0 °C. An ether solution of 3.0 M methylmagnesium bromide (6.87 mL, 20.61 mmol) was added slowly and dropwise. After 30 min at 0 °C, the reaction was quenched with saturated aqueous ammonium chloride solution. Ether was added to separate the organic and aqueous layers, and the aqueous layer was extracted with ether several times. The organic extracts were combined, dried with anhydrous sodium sulfate, filtered and concentrated in vacuum. Purification by column chromatography (n-hexane to 10% ethyl acetate/hexane gradient elution) afforded the target product 2,5-dichloro-4-methylpyrimidine as a white solid (1.45 g, 65% yield).1H NMR (500 MHz, CDCl3): δ 8.47 (s, 1H), 2.61 (s, 3H).