Fluorescence Response of a 4-Trifluoroacetylaminophthalimide to Iodide Ions upon 254 nm Irradiation in MeCN

Abstract

The title trifluoroacetylaminophthalimide derivative produced a violet fluorescence (lambdaFLmax 392 nm) in MeCN, and it displayed a green emission (lambdaFLmax 506 nm) after irradiation at 254 nm in the presence of iodide ions. The corresponding amidate ion of the trifluoroacetamide was identified as the green fluorescence emitter. The deprotonation reaction may be caused by proton-abstracting solvated electrons generated by a photochemical charge--transfer-to-solvent process from I(-) to MeCN.

Application of 4-amino-N-adamantylphthalimide solvatochromic dye for fluorescence microscopy in selective visualization of lipid droplets and mitochondria

“…[17] Moreover, upon increasing solvent H-bond donor ability the fluorescence of 4-aminophthalimide is quenched. [18] Due to its high values of fluorescence quantum yield, 4-aminophthalimides were used in the cation [19] and anion sensing, [20,21,22] design of logic gates, [23] or for the labelling of nucleosides for the study of DNA-protein interactions. [24] Herein, we present the spectral and photophysical characterization of 4-amino-N-adamantylphthalimide (1), and its use in fluorescence microscopy.…”

A fluorescence turn-on probe for iodide based on the redox reaction between cupric and iodide

“…Furthermore, Leclerc and Valiyaveettil, respectively, reported thiophene-and carbazole-containing polymers as colorimetric and fluorescence quenching probes for iodide [21,22], and Corma reported pyrene covalently anchored on zeolite as a fluorescence turn-off sensor for iodide [23]. Very recently, Li's group has devised a cadmium selenide quantum dots based sensor which displayed a fluorescent quenching response to iodide [24], and Okamoto group has studied the fluorescence properties of 4-trifluoroacetylaminophthalimide in the presence of iodide upon photolysis at 254 nm in acetonitrile [25]. However, the major limitation of the known iodide probes is that they only showed a fluorescence quenching signal upon treatment with iodide.…”

Fluorescence response of 3-trifluoroacetylaminophthalimide to a Li+–I− ion pair induced by 254 nm photolysis in acetonitrile

“…In a previous study undertaken by the current authors, it was observed that 254 nm irradiation of trifluoroacetylaminosubstituted phthalimide 1 in the presence of I À resulted in deprotonation of the former to generate the corresponding amidate 1 À resulting in a marked fluorescence colour change (Scheme 1a). 5 On this basis, it was expected that phthalimide 2, which is an isomer of 1, would undergo a similar photoinduced deprotonation, and in the presence of an appropriate metal cation, M + , the resulting amidate 2 À should chelate with the cation to form an amidate complex 2M (Scheme 1b). Such a process would produce a significant change in the fluorescent properties of 2M relative to 2 and 2 À .…”

“…1b). Because DBU can effectively abstract the highly acidic amide proton of trifluoroacetamide, 5 the 535 nm emission band was reasonably assigned to the corresponding amidate ion 2 À . Thus, the 381 and 574 nm fluorescence bands of phthalimide 2 were, respectively, assigned to the amide form of 2 and its tautomer 3 afforded through the ESIPT process (cf.…”