Synthesis
3-Fluoro-4-methylpyridine To a cooled (-78℃) solution of N, N-diisopropylamine (15.92mL, 113.4mmol) in THF (14OmL) a solution of BuLi 2.5M in hexane (45.4ml, 113.4 mmol) was added dropwise over 30 minutes under an atmosphere of Argon. The mixture was stirred for 30 min. at - 78℃ and a solution of 3-fluoropyridine (10g, 103.1 mmol) in THF (5ml) was added. After 1h at -780C, the mixture was treated with MeI (7 ml, 113.4mmol) and then was allowed to reach 250C. A solution of NaHCO3 saturated (30ml) was added and the aqueous phase was extracted with diethyl ether. The organic layer was dried (MgSO4) and upon distillation the product was collected as a colourless liquid 3-Fluoro-4-methylpyridine, bp 1300C, yield 5.3 g (47percent).
References
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[2] Journal of Medicinal Chemistry, 2003, vol. 46, # 4, p. 461 - 473
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[4] Patent: US6350745, 2002, B1. Location in patent: Page column 15;16
[5] Patent: WO2006/35967, 2006, A1. Location in patent: Page/Page column 98-99
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https://doi.org/10.1039/d3an01345f [7]Zhu, J., Zhang, R., & Dong, G. (2021). Orthogonal cross-coupling through intermolecular metathesis of unstrained C(aryl)–C(aryl) single bonds. Nature Chemistry, 13(9), 836–842.
https://doi.org/10.1038/s41557-021-00757-4