Color-Tunable Cyano-Substituted Divinylene Arene Luminogens as Fluorescent π-Gelators

The synthesis of three cyano-substituted divinylene pi-gelators is reported. The modulation of the color is achieved by placing the cyano groups in appropriate position of the conjugated backbone, thus modulating the donor-acceptor interaction. Variable-temperature UV-vis data have been utilized to investigate the self-assembly of the gelators 1-3 that is governed by a cooperative mechanism. A complete set of photophysical parameters (Phi(F),tau, k(r) and k(nr)) demonstrate the role of the molecular aggregation in enhanced emission upon self-assembly.