jo5b00336_si_001.pdf (3.53 MB)
Electronic Alteration on Oligothiophenes by o‑Carborane: Electron Acceptor Character of o‑Carborane in Oligothiophene Frameworks with Dicyano-Vinyl End-On Group
journal contribution
posted on 2015-05-01, 00:00 authored by So-Yoen Kim, Ah-Rang Lee, Guo Fan Jin, Yang-Jin Cho, Ho-Jin Son, Won-Sik Han, Sang Ook KangWe
studied electronic change in oligothiophenes by employing o-carborane into a molecular array in which one or both
end(s) were substituted by electron-withdrawing dicyano-vinyl group(s).
Depending on mono- or bis-substitution at the o-carborane,
a series of linear A1-D-A2 (1a–1c) or V-shaped A1-D-A2-D-A1 (2a–2c) oligothiophene chain structures
of variable length were prepared; A1, D, and A2, represent dicyano-vinyl, oligothiophenyl, and o-carboranyl groups, respectively. Among this series, 2a shows strong electron-acceptor capability of o-carborane
comparable to that of the dicyano-vinyl substituent, which can be
elaborated by a conformational effect driven by cage σ*−π*
interaction. As a result, electronic communications between o-carborane and dicyano-vinyl groups are successfully achieved
in 2a.