Highly selective and sensitive receptor for Fe3+ probing

Abstract A new fluorescent receptor 1,1′-(4-methylbenzene-1,3-diyl)bis[3-(2-sulfanylphenyl)urea] ( 1 ) has been designed and synthesized. The receptor showed excellent selectivity for Fe 3+ in DMSO/H 2 O (8:2, v/v) solvent system over other commonly coexistent metal ions. The binding constant ( K a ) of receptor with Fe 3+ was calculated to be 11,250 M −1 , 12,970 M −1 and 12,970 M −1 using Benesi–Hildebrand, Scatchard and Connor plot, respectively. The experimental results have been further supported by the detailed DFT calculations.