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Purpose This paper aims to prepare third-order nonlinear optical (NLO) organic materials with large nonlinear optimization value, high damage threshold and ultrafast response time. Design/methodology/approach A series of novel symmetric and asymmetric compounds possessing third-order NLO properties were synthesized using 1,3,5-tribromobenzene as the basis. The photophysical and electrochemical properties, as well as the click reactions, were characterized by means of UV–VIS–NIR absorption spectroscopy and cyclic voltammetry. Findings The donor–acceptor chromophores were inserted into compound, making the molecule to have a broader absorption in the near-infrared regions and a narrower optical and electrochemical band gap. It also formed an electron-delocalized organic system, which has larger effects on achieving a third-order NLO response. The third-order NLO phenomenon of benzene ring complexes was experimentally studied at 532 nm using Z-scan technology, and some compounds showed the expected NLO properties. Originality/value The click products exhibit more NLO phenomena by performing different click combinations to the side groups, opening new perspectives on using the system in a variety of photoelectric applications.

To investigate the self-assembly behavior of π-conjugated ethynyl-pyrene discotic derivatives, a series of ethynyl-pyrene discotic materials were designed and synthesized by Sonogashira coupling reaction. The π-conjugated structures were characterized by 1H-NMR, IR spectroscopy, and elemental analysis. The optical properties of the discotic materials were examined by UV/Vis spectra and fluorescence emission spectra. The band gap of each compound was calculated by cyclic voltammetry with UV/Vis spectroscopy. Interestingly, the substituted groups in the four symmetrical positions did affect the self-assembly properties of as-resulted nano/micro structures. Under the same conditions, compounds 4a–4d could be self-assembled into different morphologies such as micro-tubes (for 4a), micro-wires (for 4b and 4c), and micro-grain crystals (for 4d). All of the results indicated that the discotic materials have the potential for optoelectronic applications.

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