Detection of Hg2+ and Cs+ with a Rhodamine–based Sensor and Ethoxy–substituted Dihydroimidazole Ring Formation Associated with the Reduction of Hg2+ to Hg. Issue 3 (27th January 2017)

• Record Type: Journal Article
• Authors: Kumar, Ashish; Sain, Dibyendu; Kumari, Chanda; Dey, Swapan
• Is Part Of: ChemistrySelect. Volume 2:Issue 3(2017)
• Page Start: 1106
• Page End: 1110
• Publication Date: 2017-01-27
• Subjects: CS2 linkage -- Fluorescent sensor -- Imidazole formation -- Mercury reduction -- Rhodamine; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.201601457
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: Rhodamine based CS2 linked chemosensor (R1 ) was synthesized under green condition and it was applied instantly for the detection of Hg 2+ ion. WhileR1 was refluxed with Hg 2+ in ethanol, metal ion induced substitution reaction of ethoxy moiety onto imidazole ring via SN 2 mechanism was observed upon chemical transformation. The hydroxide ion, transferred to the xanthene ring followed by reduction of Hg 2+ to Hg was found. Despite of Hg 2+, R1 also exhibited very sharp sensing ability for Cs + at its very low concentration among all other metal ions. Sensing phenomena was established through UV‐Vis, fluorescence, NMR and mass spectroscopic techniques. Quantum chemical (DFT) calculation was supportive to establish all the complexation. Abstract : Rhodamine based sensors (R1) showed an excellent result by detecting Hg 2+ and Cs + in MeOH‐H2 O with off‐on mechanism. R1 reduced Hg 2+ to convert elemental Hg under refluxing condition in ethanol. The ethoxy moiety was introduced to newly formed dihydroimidazole ring and hydroxyl moiety was attached to the peri position of xenthane ring with the removal of 1, 2‐dibenzyldisulfane and H2 S.