Selective turn-on probes for CN- based on a fluorophore skeleton of 1,3-dihydroisobenzofuran

Two novel fluorescence turn-on cyanide probes based on the 1,3-dihydroisobenzofuran skeleton have been designed and synthesized: a terpyridyl-Cu2+ ensemble sensed CN- in THF-H2O (1:1, v/v), and a dicyanovinyl-containing compound sensed CN- in CH2Cl2 and THF. Titration of CN- with terpyridineCu(2+) complex caused a displacement reaction that turned on the fluorescence of A-Cu2+ at 605 nm. The detection limit of A-Cu2+ for CN- was calculated to be 3.15 x 10(-8) M. In the presence of CN-, the dicyanovinyl-bearing probe underwent a nucleophilic addition, showing 85-fold enhancement of fluorescence, with a detection limit of 5.39 x 10(-8) M. Our results demonstrate that these two strategies for designing a fluorophore skeleton based on the 1,3-dihydroisobenzofuran lead to highly selective turn on probes for CN-. (C) 2016 Elsevier Ltd. All rights reserved.