Tunable Regioselectivity in C H-Activated Direct Arylation Reactions of Dithieno[3,2-b:2',3'-d]pyrroles

In this study, regioselectively controlled direct arylation of dithieno[3,2-b:2,3'-d]pyrroles (DTPs) is reported. By carefully selecting the catalytic system, Pd source, ligand, and additives, we achieved either selective N-arylation or unprecedented beta-arylation and beta,beta'-diarylation of the DTP core through C-H activation when reacting unsubstituted H-DTP with 9-anthracenyl halides. For N-substituted DTPs, we obtained regioselective carboxylate-assisted arylation of the alpha-position(s). Consequently, depending on the catalytic system and substitution at the DTP nitrogen, we successfully synthesized novel regioselectively substituted DTPs, including N-aryl, rarely reported beta-aryl, beta-beta'-diaryl, alpha-aryl, and alpha,alpha'-diaryl scaffolds. These compounds can be straightforwardly prepared and further functionalized for applications as organic electronic materials.