Selenophene-Based Heteroacenes: Synthesis, Structures, and Physicochemical Behaviors

On the basis of three new building blocks, dithieno­[3,2-b:2′,3′-d]­selenophene (tt-DTS), diseleno­[3,2-b:2′,3′-d]­thiophene (tt-DST), and diseleno­[3,2-b:2′,3′-d]­selenophene (tt-DSS), four thiophene- and selenophene-based heteroacenes (3a–d) with up to seven fused rings were designed and synthesized. Another two selenophene-based heteroacenes (1 and 2) with three and five fused rings were prepared. The molecular structures of 1, 2, 3a, and 3c were confirmed by single-crystal analysis. The results showed that molecular structures, spectroscopy features, and cyclic voltammetry behaviors could be modulated by changing the heteroatoms from sulfur to selenium for 3a–d or changing the numbers of selenophene rings for 1, 2, and 3d.