87674-21-3

Step 2: Synthesis of 1-(3-fluoropyridin-4-yl)ethanone To a stirred solution of 3-fluoro-N-methoxy-N-methylpyridine-4-carboxamide (1.2 g, 6.5 mmol) in tetrahydrofuran (THF) (15 mL) was slowly added methylmagnesium bromide (2M solution in THF, 16 mL, 32 mmol) at 0 °C. After addition, the reaction mixture was brought to room temperature and stirring was continued for 2 hours. Upon completion of the reaction, the reaction was quenched with saturated ammonium chloride (NH4Cl) solution and subsequently extracted with ethyl acetate (EtOAc). The organic layers were combined, washed sequentially with water and saturated saline, dried over anhydrous sodium sulfate (Na2SO4), and concentrated under reduced pressure to afford 0.650 g (92% yield) of the target product 1-(3-fluoropyridin-4-yl)ethanone as a colorless oil. Mass spectrum (MS): 140.1 [M+H]+.

[1] Patent: US2017/291894, 2017, A1. Location in patent: Paragraph 0486-0488
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[3] Patent: WO2009/114552, 2009, A1. Location in patent: Page/Page column 167