Synthesis
A mixture of tetrakis(triphenylphosphine)palladium(0) (1.45 g, 1.25 mmol) and potassium carbonate (17.5 g, 127 mmol) was added as 3,5-dibromopyridine (10.0 g, 42.2 mmol) and phenylboronic acid (4.6 g, 38.0 mmol). The reaction mixture was dissolved in a solvent mixture of water (63 ml) and 1,2-dimethoxyethane (126 ml) and the reaction was stirred under reflux conditions overnight. Upon completion of the reaction, the reaction was neutralized by addition of aqueous sodium hydroxide (1M, 60 ml), followed by extraction with ether (100 ml) twice and combining the organic phases. Purification was carried out by silica gel column chromatography using dichloromethane as solvent to afford the target product 3-bromo-5-phenylpyridine. The yield was 6.1 g in 68% yield and the melting point was 42-44 °C.
References
[1] Journal of Materials Chemistry C, 2014, vol. 2, # 47, p. 10129 - 10137
[2] Patent: US2004/72823, 2004, A1. Location in patent: Page/Page column 20
[3] Patent: US2004/72823, 2004, A1. Location in patent: Page/Page column 15
[4] Bioorganic and Medicinal Chemistry Letters, 2013, vol. 23, # 14, p. 4145 - 4149
[5] Organic and Biomolecular Chemistry, 2016, vol. 14, # 24, p. 5820 - 5825
