Benzimidazole based ratiometric chemosensor for detection of CN− and Cu2+ ions in protic/aqueous system: Elaboration as XOR logic operation

• Synthesis of benzimidazole based ESIPT sensor.
• Ratiometric sensor for cyanide and copper ions in protic/aqueous system.
• Broad range of cyanide and copper ion detection.
• Practical usability of probe 1 as XOR logic gates.

ESIPT based benzimidazole derivative probe 1 with electron withdrawing group has been synthesized and investigated their photophysical behavior towards various anions. The probe 1 has been used for selective estimation of CN− and signaled the binding event through formation of new absorption band at 380 nm and emission band at 430 nm with CN−. The addition of various metal ions to probe 1 in aqueous system showed selectivity towards Cu2+ and Hg2+ ions as compared to other metal ions, and signal the binding event through formation of new absorption band at 375 nm and decrease in absorption intensity respectively. Thus, probe 1 act as chemosensor for CN− ions which restricts the ESIPT emission at 485 nm due to H-bonding interactions between OH to nitrogen of benzimidazole moiety to release its enol emission. The chemical inputs of CN− and Cu2+ ions to probe 1 mimicked a sequence dependent operation of an exclusive-OR (XOR) logic gate. The binding behavior of probe 1 towards CN− and Cu2+ has also been confirmed through DFT calculations.

ESIPT based benzimidazole derivative probe 1 as sensor for CN− amongst anions, Cu2+ and Hg2+ ions sensor amongst metal ions. The chemical inputs of CN− and Cu2+ ions to probe 1 mimicked a sequence dependent operation of an exclusive-OR (XOR) logic gate.Figure optionsDownload as PowerPoint slide