Synthesis
General procedure for the synthesis of 4-(2-pyridyl)-benzaldehyde from 2-bromopyridine and 4-formylphenylboronic acid: 1.1 equiv. of the brominated derivatives (13- of 2-bromopyridine and 14- of 1-bromo-4-nitrobenzene) of 4-formylphenylboronic acid, Pd(OAc)2 (2 mol%), and PPh3 (4 mol%) were added to a Schlenk flask. Methanol/THF (1:1, 2 mL/mmol) and 2 eq. of KOH were added under an inert atmosphere. the reaction system was stirred at 60 °C for 24 h. The reaction system was then purified by column chromatography. The target compounds were purified by column chromatography (eluent: cyclohexane/EtOAc, 9:1) to afford the products 13a and 14a in 80% and 75% yields, respectively.
References
[1] European Journal of Organic Chemistry, 2008, # 12, p. 2049 - 2055
[2] Angewandte Chemie - International Edition, 2015, vol. 54, # 47, p. 14103 - 14107
[3] Angew. Chem., 2015, vol. 127, # 47, p. 14309 - 14313,5
[4] Organic and Biomolecular Chemistry, 2013, vol. 11, # 39, p. 6806 - 6813
[5] European Journal of Organic Chemistry, 2014, vol. 2014, # 27, p. 5901 - 5905
