C2-symmetrical hexaazatriphenylene derivatives as colorimetric and ratiometric fluorescence chemsensors for Zn2+

► C2-symmetrical hexaazatriphenylene based chemsensors 1 and 2 were synthesized. ► 1 and 2 exhibit ratiometric and colorimetric fluorescene selectivity for Zn2+. ► The color changes between 1 or 2 with Zn2+ can be observed by naked eyes. ► 1, 2 are sensitive to Zn2+ with detection limits of 0.2 and 0.095 μM, respectively.