Synthesis
2,5-dibromopyridine (20.0 g, 84.4 mmol), dibenzo-18-crown-6 (1.5 g, 4.2 mmol), benzyl alcohol (11.9 g, 11.4 mL, 109.8 mmol), and potassium hydroxide (11.4 g, 202.6 mmol) were mixed in toluene (200 mL) and assembled with a Dean-Stark distributor, and the reaction was refluxed for 1.5 hours. Upon completion of the reaction, the solvent was removed by distillation under reduced pressure. The residue was diluted with water and extracted with chloroform. The organic phase was separated, dried with anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by silica gel column chromatography (eluent: hexane/ethyl acetate, 98:2, v/v) and subsequently recrystallized from hexane to give 2-benzyloxy-5-bromopyridine (20.6 g, 92% yield) as a colorless solid.
References
[1] Journal of Organic Chemistry, 1995, vol. 60, # 5, p. 1408 - 1412
[2] Polyhedron, 2013, vol. 52, p. 755 - 760
[3] Patent: WO2004/43926, 2004, A1. Location in patent: Page 150
[4] Patent: WO2004/69805, 2004, A1. Location in patent: Page 55
[5] Patent: US2009/82403, 2009, A1. Location in patent: Page/Page column 66
