Di- and tetramethoxy benzothienobenzothiophenes: substitution position effects on the intermolecular interactions, crystal packing and transistor propertiesElectronic supplementary information (ESI) available: Additional information for synthesis, electrochemical measurements, theoretical calculations, single-crystal X-ray analysis, device fabrication, and thin-film X-ray analysis. CCDC 1539947 and 1539948 contain the supplementary crystallographic information for compound 7 and BTBT(OMe)4, resp

• Main Authors: Higashino, Toshiki, Ueda, Akira, Mori, Hatsumi
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/c8nj04251a

We report the synthesis, structures, and transistor properties of benzothienobenzothiophene (BTBT) derivatives tailored by introducing methoxy groups at the 2,3- and 2,3,7,8-positions (2,3-dimethoxy-BTBT: BTBT(OMe) 2 and 2,3,7,8-tetramethoxy-BTBT: BTBT(OMe) 4 ). Both of these compounds form a herringbone packing in the crystal; however, their molecular arrangements are significantly different: the tetramethoxy derivative BTBT(OMe) 4 shows no dimerization, whereas the dimethoxy derivative BTBT(OMe) 2 shows significant tetramerization with two dimers. This difference, attributable to the difference in the substitution pattern of the methoxy groups or the molecular symmetry, leads to a drastic difference in their charge transport properties. In the vapor-deposited thin films, BTBT(OMe) 4 exhibits a crystalline architecture similar to the bulk phase stabilized by weak hydrogen bonds, showing good p-channel transistor performance, while BTBT(OMe) 2 exhibits an amorphous-like structure without any observable transport properties. The relationship between the structure and transistor properties of novel benzothienobenzothiophene (BTBT) derivatives with 2,3-dimethoxy and 2,3,7,8-tetramethoxy groups was investigated.