A new spiro-cyclopentadithiophene-based hole transport material has been developed for perovskite solar cells exhibiting an excellent power conversion efficiency of 13.4% without the use of any additives and dopants.

Heteroacenes developed to widely used building blocks in organic semiconductors for application in organic electronics due to their tunable structures and properties concomitant with inherent stability. Here, we report efficient preparation and investigation of so far unknown heterotriacenes, basic anti-and syn-dithienopyrazine 5 and 6. The comparison of the two isomers with respect to electronic properties and follow-up reactions gives insights into structure-property and -reactivity relationships. Examples of transition metal-catalyzed CÀ C crosscoupling reactions of corresponding halogenated derivatives show the practical impact for extended π-conjugated systems applied in optoelectronic devices.

Dithienopyrazines are only scarcely used as building blocks in organic electronic materials. Here, we report efficient preparation and investigation of syn-and anti-dithienopyrazines, which were functionalized with triaraylamine units to provide different series of donor-acceptor-donor-type materials. The characterization of the optoelectronic properties resulted in valuable structure-property relationships and allowed for the elucidation of the influence of structural effects such as core structure (syn vs anti), type of substituents (directly arylated vs ethynylated aryl), and substitution pattern (α,α'-vs β,β'vs fourfold substitution). Finally, first application of a dithienopyrazine derivative as model for hole-transport materials tailored for organic electronic devices has been realized.

Heteroacenes developed to widely used building blocks in organic semiconductors for application in organic electronics due to their tunable structures and properties concomi¬ant with inherent stability. Here, we report efficient preparation and investigation of so far unknown heterotriacenes, basic anti- and syn-dithienopyrazines 5 and 6. The comparison of the two isomers with respect to electronic properties and follow-up reactions gives insights into structure-property and -reactivity relationships. Examples of tran¬sition metal-catalyzed C-C cross-coupling reactions of corresponding halogenated derivatives show the practical impact for extended pi-conjugated systems applied in optoelectronic devices.