Substituent effects on anion sensing of salicylidene Schiff base derivatives: Tuning sensitivity and selectivity

Synthesis of novel azo linkage-based Schiff bases including anthranilic acid andhexanoic acid moieties: investigation of azo-hydrazone and phenol-ketotautomerism, solvatochromism, and ionochromism

“…anions exist in solvated form. 46 These influence receptor-anion interactions and complicate the detection of anions.…”

Dual-Mode Multiple Ion Sensing via Analyte-Specific Modulation of Keto–Enol Tautomerization of an ESIPT Active Pyrene Derivative: Experimental Findings and Computational Rationalization

“… 35 − 43 However, most surprisingly, there is almost no pyrene-based ESIPT active probe that has been utilized in the detection and imaging of analytes. 44 Unsurprisingly, the uniqueness and novelty of the present report are still significant in this sense. Moreover, a comparison table is designed assembling the ESIPT active probes that are involved in colorimetric and/or fluorescent detection of Cu 2+ and Zn 2+ ions.…”

“…However, PMHMP exhibited faint-blue fluorescence (Φ = 0.04) under a long UV lamp, which might be due to the efficient photo-induced electron transfer (PET) attributed to the lone pair of electrons on the nitrogen atoms . In addition, a broadband with relatively low intensity was observed in the 567 nm region, which might be due to emission from the keto tautomer. , To prove this, we recorded the fluorescence spectrum in the CH 3 CN–water (1:1) mixture medium, which displayed a significant increase in emission intensity at 575 nm (Figure S3, Supporting Information). Thus, we can comment that the fluorescence maxima of PMHMP at 432 and 565 nm in the CH 3 CN medium probably originated from the enol and keto tautomers, respectively, ascertaining the ESIPT phenomenon of PMHMP .…”

“…The fluorophore PMHMP was synthesized by following the procedure reported in the literature 44 and characterized accordingly (Scheme 1, Supporting Information ). A weak peak characterizes the UV–vis spectrum of PMHMP in the 300 nm region, presumably caused by the n−π* transition of the C=N group.…”

“…The excited-state intramolecular proton transfer (ESIPT) is one of the most popular photoprocesses in the field of colorimetric and fluorescent detection. The ESIPT behavior of the fluorophore PMHMP (Scheme ) can be well presented in Figure . − Naturally, monitoring of the “on–off” switching between the tautomers of an ESIPT active probe and the detection and imaging of important cations, vital anions, and biological molecules have been achieved during the last 2 decades. − However, most surprisingly, there is almost no pyrene-based ESIPT active probe that has been utilized in the detection and imaging of analytes . Unsurprisingly, the uniqueness and novelty of the present report are still significant in this sense.…”