“…One of the earliest examples of a Suzuki reaction of a heteroaryl chloride was provided by Gronowitz et al, who examined the coupling of 2,4‐dichloropyrimidine with 2‐thienylboronic acid and established that the 4‐chloro group is more reactive than the 2‐chloro group [Eq. (3)] 12, 13. Subsequently, other chloro‐substituted nitrogen heterocycles have been shown to undergo Suzuki coupling in the presence of traditional palladium catalysts including pyridines,13a–13c, 14 pyridine N ‐oxides,14h pyrazines,12d, 13b–13d, 15 pyridazines,12d, 16 triazines,13e, 13g, 17 quinolines,13c, 18 isoquinolines,13a, 19 quinazolines,20 cinnolines,20b phthalazines,21 β‐carbolines,22 phenanthrolines,23 imidazo[1,2‐ b ]pyridazines,24 pyrazolo[1,5‐ a ]pyrimidines,18b pyrazolopyrimidines,13e triazolopyrimidines,13e pyrrolopyrimidines,13e and purines 25…”