S,N-Heteroacenes Up to a Tridecamer

• Published in: Chemistry of materials Vol. 31; no. 17; pp. 7007 - 7023
• Main Authors: Brier, Eduard, Wetzel, Christoph, Bauer, Michael, Mena-Osteritz, Elena, Wunderlin, Markus, Bäuerle, Peter
• Format: Journal Article
• Language: English
• Published: American Chemical Society 10.09.2019
• ISSN: 0897-4756; 1520-5002
• DOI: 10.1021/acs.chemmater.9b01652

Herein, syntheses of extended π-conjugated ladder S,N-hetero­acenes from the octamer to the tridecamer and their physical properties are described. Motivated by previous results on shorter members of this family, we further extended the number of annulated thiophene and pyrrole rings in our S,N-hetero­acene series up to 13. The synthetic strategy to achieve the hetero­acene scaffolds comprised multiple ring closures by transition metal-catalyzed C–S and C–N coupling/cyclization reactions, leading to fused thiophene or pyrrole rings, respectively. The extended S,N-hetero­acenes comprising varying sequences of hetero­atoms were fully characterized by NMR, high-resolution mass spectrometry, UV–vis and fluorescence spectroscopy, and cyclic voltammetry. Furthermore, stable radical cations and dications were formed by controlled oxidation of the hetero­acenes and optically characterized. Valuable structure–property relationships concerning the optoelectronic properties were deduced.