ESIPT-based anthraquinonylcalix[4]crown chemosensor for In 3+

Abstract An ESIPT-based novel fluorescent chemosensor, 1,8-anthraquinonylcalix[4]monocrown-6 ( 1 ), which displayed a selective fluorescent change with In 3+ among various metal ions, was rationally designed and synthesized. Upon the addition of In 3+ , the probe displayed a fluorescence decrease at 625 nm, at the same time, an increase of the band centered at 535 nm was observed. This sensing process was also proved by the 1 H NMR titration and electrochemical tests.