Novel sensitive sensors for Cu2+ and optical switching of photochromic dithienylethene derivatives

•Two novel diarylethene with an imidazole-containing substituent were synthesized.•They could serve as highly selective ‘naked-eye’ colorimetric sensors for Cu2+.•One could respond to Sn2+ with fluorescence and thus a logic circuit was constructed.

Two novel asymmetrical diarylethenes with an imidazole-containing substituent have been synthesized. The two diarylethenes exhibited favorable photochromism and functioned as fluorescence switches upon alternating ultraviolet and visible light irradiation. These two compounds could also serve as highly selective ‘naked-eyes’ colorimetric sensors for Cu2+. Furthermore, the diarylethene with a 1H-phenanthro[9,10-d]imidazole unit was selective toward Sn2+, Al3+, and Cr3+ with remarkable fluorescence changes. Based on this characteristic, a logic circuit was constructed by utilizing the combinational stimuli of chemicals and light as the inputs and fluorescence intensity at 444 nm as the output.

Graphical abstractTwo novel asymmetrical photochromic dithienylethenes with a 1H-imidazo[4,5-f][1,10] phenanthroline and a 1H-phenanthro[9,10-d]imidazole moiety were designed and synthesized. Their photophysical properties, including photochromism, fluorescence, and recognition of metal ions, were systematically investigated.Figure optionsDownload full-size imageDownload as PowerPoint slide