title: Synthesis and Isomeric Effects of Ladder-Type Alkylated Terbenzodithiophene Derivatives.
abstract: A new class of heptacyclic ladder-type terbenzodithiophene (TBDT) structures merging three fused benzodithophenes was developed. Two TBDT conjugated isomers, named as syn-TBDT and anti-TBDT, where the two thienyl rings in the outmost BDT units are in the syn- and anti-fashion, are designed. Two decyl groups are introduced to their 6,13 and 7,14-positions to form four isomeric 6,13-syn-TBDT, 7,14-syn-TBDT, 6,13-anti-TBDT, and 7,14-anti-TBDT structures which are constructed by the DBU-induced 6-benzannulation involving propargyl-allenyl isomerization of the dieneyne moieties in the corresponding precursors followed by 6π-electrocyclization/aromatization, while isomeric TD-syn-TBDT and TD-anti-TBDT with four decyl groups substituted at 6,7,13,14-positions are synthesized via palladium-catalyzed dialkylacetylene insertion/C-H arylation of the corresponding iodobiaryl precursors. The intrinsic properties can be modulated by molecular manipulation of the main-chain and side-chain isomeric structures. anti-TBDT derivatives exhibit higher melting points, larger bandgaps, stronger intermolecular interactions, and higher mobility than the corresponding syn-TBDT analogues. These molecules can be further utilized as building blocks to make various TBDT-based materials for optoelectronic applications.
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University , 1001 University Road, Hsin-Chu, 30010 Taiwan.
authors.forename: Yung-Lung
authors.initials: YL
authors.lastname: Chen
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University , 1001 University Road, Hsin-Chu, 30010 Taiwan.
authors.forename: Jhih-Yang
authors.initials: JY
authors.lastname: Hsu
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University , 1001 University Road, Hsin-Chu, 30010 Taiwan.
authors.forename: Fang-Yu
authors.initials: FY
authors.lastname: Lin
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University , 1001 University Road, Hsin-Chu, 30010 Taiwan.
authors.forename: Yu-Ying
authors.initials: YY
authors.lastname: Lai
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University , 1001 University Road, Hsin-Chu, 30010 Taiwan.
authors.forename: Hsiao-Chieh
authors.initials: HC
authors.lastname: Chou
authors.affiliation: Department of Applied Chemistry, National Chiao Tung University , 1001 University Road, Hsin-Chu, 30010 Taiwan.
authors.forename: Yen-Ju
authors.initials: YJ
authors.lastname: Cheng