A Proton-Triggered ON−OFF−ON Fluorescent Chemosensor for Mg(II) via Twisted Intramolecular Charge Transfer

Abstract

A novel fluorescent chemosensor has been synthesized and shows interesting fluorescent ON-OFF-ON processes through mediating its twisted intramolecular charge transfer (TICT) state. An exclusively fluorescent enhancement is observed for Mg (2+).

Aggregation-induced blue shift of fluorescence emission due to suppression of TICT in a phenothiazine-based organogel

“…It is well-known that the twisted intramolecular charge transfer (TICT) probe molecules may give color-tunable fluorescence emission depending on the polarity of solvents [20][21][22]. In other words, the TICT is not only affected by the conformational relaxation of the excited molecule itself [23,24], but also quite sensitive to the external environment. Therefore, it seems evident that the alignment of the organogelators with TICT emission in the gel phase will have an effect on the conformational changes between the ground and the excited states, resulting in unusual photophysical properties.…”

Synthesis and fluorescent sensory properties of a 5-cyanostilbene derivative linked to monoaza-15-crown-5

“…However, in toluene H-Crown shows fluorescence peak (415 nm including shoulder at about 440 nm) similar to CNCrown at 417 nm and 445 nm ( Fig. 1 (Liu et al, 2008).…”

Six‐Membered Rings with One Oxygen: Pyrylium Ion, Related Systems and Benzo‐Derivatives

“…This method is an alternative for the preparation of pyridines with some particular substitution patterns. In the example presented in Scheme 18.15 a pyridine carrying a benzo-15-crown-5 (67), which is a fluorescent sensor for Mg(II), is prepared through a straightforward two step sequence that involves: (i) formation of the pyrylium perchlorate 66 by the classical reaction of an aromatic aldehyde (65) with acetophenone and (ii) treatment with ammonium acetate to give the desired pyridine 67 (Scheme 18.15) [25].…”