2-Aza-1,3-butadiene derivatives featuring an anthracene or pyrene unit: highly selective colorimetric and fluorescent signaling of Cu2+ cation.

[Structure: see text] A new probe based on an anthryl derivative bearing an azadiene side chain selectively senses Cu2+ in acetonitrile through two different channels: the yellow-to-orange color change and a remarkable enhancement of the fluorescence, whereas the pyrenyl analogous behaves as a fluorescent sensor for Cu2+ and Hg2+ in aqueous environment.