A rhodamine 6G derivative as "turn-on" fluorescent probe for Cu2+. Spectroscopy, single crystal structure and DFT calculations. (28th May 2017)

• Record Type: Journal Article
• Authors: Li, Tianrong; Yang, Yang; Zhou, Panpan; Peng, Zhou; Qin, Jingcan; Liu, Li; Wang, Yuhua
• Is Part Of: Polyhedron. Volume 128(2017)
• Page Start: 154
• Page End: 159
• Publication Date: 2017-05-28
• Subjects: Cu2+ -- Fluorescence detection -- Turn-on -- Rhodamine 6G -- Single crystal; Chemistry, Inorganic -- Periodicals; Chimie inorganique -- Périodiques; Organometaalverbindingen; Anorganische chemie; 546.05
• DOI: 10.1016/j.poly.2017.03.014
• Languages: English
• ISSNs: 0277-5387

Abstract

Graphical abstract: Sensor1, 1-phenyl-3-methyl-5-hydroxypyrazole-4-benzoyl(rhodamine 6G) hydrazone, showed a "turn-on" fluorescence response to Cu 2+ among common cations (Na +, K +, Mg 2+, Ca 2+, Mn 2+, Co 2+, Ni 2+, Zn 2+, Cd 2+, Cr 3+, Fe 3+ and Cu 2+ ) selectively and sensitively. The single crystals of1– Cu 2+ complex definitely support the corollary that after chelating with Cu 2+, an open cycle structure is formed in rhodamine moiety. Abstract: In order to achieve an effective "turn-on" fluorescence detection of Cu 2+, a rhodamine 6G-based sensor [1-phenyl-3-methyl-5-hydroxypyrazole-4-benzoyl(rhodamine 6G) hydrazone, 1 ] was prepared. Fluorescence and UV–Vis absorption titration, detection limit, single crystal structure, binding mode, and quantum mechanical calculation studies were also discussed in detail. Sensor1 showed highly selectivity and sensitivity to Cu 2+ among common cations (Na +, K +, Mg 2+, Ca 2+, Mn 2+, Co 2+, Ni 2+, Zn 2+, Cd 2+, Cr 3+, Fe 3+ and Cu 2+ ) in acetonitrile. Upon addition of Cu 2+, a new absorption band at 523 nm, and a strong emission band centering at 557 nm appeared in1 solution. Relevant solution changed from colorless to purple, and an obvious orange fluorescence emission was given. A maximum fluorescence enhancement of 250 times at 557 nm could be made by addition of 6 equivalent of Cu 2+ . The fluorescence detection limit was calculated to be 2.5 μM (0.20 ppm) for Cu 2+, and 1:1 stoichiometry between Cu 2+ and1 was proved. In the single crystal of1 –Cu 2+ complex, rhodamine moiety exhibited an open cycle form. We believe1 can be a good candidate for the fluorescence detection of Cu 2+ .