Nitro substituted chalcone derivatives as quick-response chemosensors for cyanide anions

Three nitro substituted chalcone derivatives with diethylamino (1), carbazolyl (2) and pyrene (3) as terminal group have been synthesized via typical condensation reaction of 2-hydroxy-4-nitro-acetophenone with related aryl-aldehydes in good yields. Their crystal structure and recognition properties for cyanide anions have been investigated. The results indicated that all the compounds exhibit quickly obvious UV–vis absorption and fluorescence response to cyanide anions in aqueous solution. Especially, compound 1 with diethylamino as terminal group exhibits obvious fluorescence change from orange to green with fluorescence turn-on response upon the addition cyanide anions.