The synthesis and fluorescent characteristics of some heteroaromatic derivatives of 2,2′-bithienyl

Abstract

A series of novel, fluorescent derivatives of 2,2′-bithienyl has been prepared and the influence of structure on the absorption and emission spectra has been examined; the substituents introduced in this study were 2-quinolyl, 2-benzoxazolyl, 2-benzothiazolyl (all at the 5-position), 2-benzimidazolyl and 2-indolyl (3- or 5-position). The influence of solvent has also been investigated. For all but the indolyl derivatives, the spectral changes—bathochromic shifts with increasing solvent hydrogen-bonding character—were consistent with π–π* emission. In the exceptional cases, small hypsochromic shifts were observed on increasing solvent polarity.