Synthesis and functionalization of fused dithieno-heterocycles for the preparation of optoelectronic materials

Fused tricyclic heterosystems, such as dithieno[3,2-b:2',3'-d]pyrroles (DTPs), -siloles (DTSs), -phospholes (DTPhs), and -thiophenes (DTTs), show high stability and robustness, while molecules containing these scaffolds usually exhibit remarkable optical and electrochemical properties, which make them particularly interesting for applications in the field of optoelectronics. Their synthesis can usually be accomplished through the formation of a properly substituted 2,2’-bithienyl derivative able to cyclize after the introduction of the desired heteroatom. Pd-catalyzed cross-coupling reactions are the best choice for introducing additional functional groups and modulating the properties of the final molecules according to the designated application.