Synthesis
Example 2.26: Synthesis of methyl 5-fluoronicotinate; To a stirring solution of 243 mg (1.6 mmol) of methyl 5-aminonicotinate dissolved in 5 mL of HF-pyridine at 0 °C was slowly added 119 mg (1.72 mmol) of sodium nitrite (NaNO2). The reaction mixture was stirred continuously at 0 °C for 30 min, then warmed up to 50 °C and kept for 1 hour. Upon completion of the reaction, the reaction was quenched with ice and saturated sodium bicarbonate (NaHCO3) solution. The aqueous phase was extracted with chloroform (CHCl3) and the organic phase was dried over anhydrous sodium sulfate (Na2SO4), filtered and concentrated. Purification by fast silica gel column chromatography (eluent: 1% methanol/chloroform) afforded 139 mg of methyl 5-fluoronicotinate as a yellow solid in 56% yield.
References
[1] Patent: WO2006/110668, 2006, A1. Location in patent: Page/Page column 62
[2] Journal of Organic Chemistry, 1949, vol. 14, p. 328,331
[3] Angewandte Chemie - International Edition, 2018, vol. 57, # 31, p. 9896 - 9900
[4] Angew. Chem., 2018, vol. 130, p. 10044 - 10048,5