KCN sensor: unique chromogenic and 'turn-on' fluorescent chemodosimeter: rapid response and high selectivity

An indole conjugated coumarin 1 for KCN chemodosimeter has been prepared and displayed considerable dual changes in both absorption (blue-shift) and emission (turn-on) bands exclusively for KCN. DFT/TDDFT calculations support that the fluorescence enhancement of 1-KCN is mainly due to blocking of the ICT process.