Synthesis and Photophysical studies of imidazo[4,5- f][1,10]phenanthroline derivative and it’s Ru (II) complex

Abstract

Chemosensors (1 & 2) based on imidazo[4,5-f][1,10]phenanthroline incorporating indole and its corresponding Ru (II) complex were synthesized. The photophysical characteristics of chemosensor 1 were assessed using UV-visible and fluorescence spectroscopy in DMSO: EtOH (1:1). The absorption band at 289 nm displayed bathochromic shift of 29 nm (new band at 318 nm) exclusively with the addition of DCP ions. Interestingly, in the emission spectrum quenching was observed with DCP ions along with pyrophosphate with the detection limits 68 nm and 4.2 μM respectively. However, photophysical characteristics of chemosensor 2 were evaluated in Water: DMSO (9:1) system. Chemosensor 2 exhibited excellent selectivity for CN- ions as the emission intensity at 608 nm was only quenched with CN- ions demonstrating LOD value of 55 nm. The sensing process of both the chemosensors 1 & 2 was not interfered by any of the competing ions. Further, for both the chemosensors, no spectral change was observed with any of the added cations in absorption as well as emission spectra.