Intramolecular Charge-Transfer Behavior of 1-Pyrenyl Aromatic Amides and Its Control through the Complexation with Metal Ions

Abstract

New fluorescent ionophores containing 1-pyrenyl aromatic amides based on oligoethylene oxide (1 and 2) have been synthesized and its photochemical behaviors have been studied. In the absence of metal ion, 1-pyrenylbenzamide moiety showed almost no fluorescence emission. However, complexation with Ca2+ induced a large enhancement effect on the fluorescence intensity of 1 and 2 from the pyrene ring. This behavior can be explained by in terms of the similar twisted intramolecular charge-transfer relaxation mechanism.

Substituted Position Effect on Twisted intramolecular Charge Transfer of 1- and 2-anthracene aromatic Carboxamides as Chemosensors Based on Linear Polyether

“…[26][27][28][29][30][31][32][33][34] We also found that the fluorescence emissions of the N-phenyl-9-anthracenecarbox-amide unit (9-aa) and its derivatives (94 and 95) (Fig. 1) were almost quenched in solution.…”

New “Off-On” Responsible Fluoroionophores for Alkaline Earth Metal Ions Based on Benzo-15-crown-5 Bearing 9-Phenanthreneacetamide

“…In our previous study, all values of log K showed a similarity to crown ether compounds. 28 Consequently, all guest species were suitable for fluorescence "Off-On" controlling because of a high response to the benzo-15-crown-5 moiety.…”

“…[20][21][22][23][24][25] In earlier papers, we described several fluoroionophores based on linear polyethers having fluorescence molecules at their terminals. [20][21][22][23][26][27][28] These ionophores gave fluorescence behavior from weak to strong emission upon metal ion complexation. Recently, we also reported a new mode of PET in fluorophore connecting N-phenylamide derivatives and its applications for chemosensors based on crown ether.…”

Discriminating Detection between Mg2+ and Ca2+ by Fluorescent Signal from Anthracene Aromatic Amide Moiety

“…Chemosensors 1 and 2 (Figure ) were synthesized in the usual manner (see the Supporting Information). , Their structures and purities were respectively confirmed by using 1 H NMR and elemental analyses (see the Supporting Information). Fluorescence and UV spectra were measured at 25 °C (RF-5300PC, UV-2400PC; Shimadzu Corp.).…”