Gromov, Sergey P. Ushakov, Evgeny N. Vedernikov, Artem I. Lobova, Natalia A. Alfimov, Michael V. Strelenko, Yurii A. Whitesell, James K. Fox, Marye Anne A Novel Optical Sensor for Metal Ions Based on Ground-State Intermolecular Charge-Transfer Complexation A derivative of dipyridylethylene <b>2</b> was synthesized in order to study intermolecular coordination between the 18-crown-6 ether units of bis-crown stilbene <b>1</b> and the NH<sub>3</sub><sup>+</sup> groups of <b>2</b>. In acetonitrile solution, the formation of a supramolecular complex is evidenced by a considerable upfield shift of the <sup>1</sup>H NMR signals from the aromatic and olefinic protons. Emission quenching and the appearance of a new absorption band in the visible spectral region indicate the formation of a charge-transfer complex. The addition of Ba<sup>2+</sup> to a solution of the complex leads to significant fluorescence enhancement and to the disappearance of the charge-transfer absorption band. supramolecular;1 H NMR signals;Emission quenching;Complexation;ether;acetonitrile solution;fluorescence enhancement;Novel Optical Sensor;absorption band;dipyridylethylene 2;olefinic protons;Metal Ions;disappearance;formation;coordination;stilbene;Ba;NH 3;appearance;shift;region;Intermolecular 1999-11-01
    https://acs.figshare.com/articles/figure/A_Novel_Optical_Sensor_for_Metal_Ions_Based_on_Ground-State_Intermolecular_Charge-Transfer_Complexation/3760305
10.1021/ol990710d.s002