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Suzuki–Miyaura coupling reaction of BrC6H4‐X‐C6H4Br 1 (X=CH2, CO, N‐Bu, O, S, SO, and SO2) with arylboronic acid 2 was investigated in the presence of tBu3PPd precatalyst and CsF/[18]crown‐6 as a base to establish whether or not the Pd catalyst can undergo catalyst transfer on these functional groups. In the reaction of 1 (X=CH2, CO, N‐Bu, O, and SO2) with 2, aryl‐disubstituted product 3 (Ar‐C6H4‐X‐C6H4‐Ar) was exclusively obtained, indicating that the Pd catalyst undergoes catalyst transfer on these functional groups. On the other hand, the reaction of 1 e (X=S) and 1 f (X=SO) with 2 afforded only aryl‐monosubstituted product 4 (Ar‐C6H4‐X‐C6H4‐Br) and a mixture of 3 and 4, respectively, indicating that S and SO interfere with intramolecular catalyst transfer. Furthermore, we found that Suzuki–Miyaura polycondensation of 1 (X=CH2, CO, N‐Bu, O, and SO2) and phenylenediboronic acid 5 in the presence of tBu3PPd precatalyst afforded high‐molecular‐weight polymer even when excess 1 was used. The polymers obtained from 1 (X=CH2, N‐Bu, and O) and 5 turned out to be cyclic.