The Suzuki–Miyaura reaction of 1,2- dibromo-4-fluorobenzene with two equivalents of arylboronic acids 2a–d, i,v afforded the fluorinated terphenyls 15a–f in moderate to good yields. The best yields were obtained using 2.2 equivalents of the aryl boronic acid, Pd(PPh3)4 (0.03 equiv) as the catalyst, and Cs2CO3 (2.2 equiv) as the base (1,4-dioxane, 90 8C, 8 h). The low site-selectivity in the case of 1,2-dibromo-4-fluorobenzene (13) can be explained by the fact that the positions 1 and 2, located meta and para to the fluorine atom, are sterically and electronically very similar[1].
