title: Synthesis of self-threading bithiophenes and their structure-property relationships regarding cyclic side-chains with atomic precision.
abstract: We have recently reported a self-threading polythiophene as a new family of insulated molecular wires. Herein, we focused on the structure-property relationships of the unique three-dimensional architecture of the monomer. We have synthesized nine self-threading bithiophene monomers that have cyclic side-chains of different size and flexibility: i.e., 21-, 22-, 23-, 24-, 26-, and 30-membered rings composed of paraffinic, olefinic, or alkynic chains. To investigate their structure-property relationships, (1) H NMR spectroscopy, UV absorption, and fluorescence spectroscopy measurements were conducted. We found that cyclic side-chains define the movable range of the dihedral angle of the bithiophene backbone, thereby affecting its photophysical properties. Therefore, the ability to design a structure with atomic precision as described herein would lead to the fine-tuning of the electronic properties of insulated molecular wires.
authors.affiliation: Polymer Materials Unit, National Institute for Materials Science (NIMS), Tsukuba, Ibaraki, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Ouchi
authors.forename: Kazunori
authors.initials: K
authors.lastname: Sugiyasu
authors.forename: Soichiro
authors.initials: S
authors.lastname: Ogi
authors.forename: Akira
authors.initials: A
authors.lastname: Sato
authors.forename: Masayuki
authors.initials: M
authors.lastname: Takeuchi
mesh_terms: D003500:Cyclization; D008958:Models, Molecular; D015394:Molecular Structure; D013876:Thiophenes / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D013876:Thiophenes