A fluorescent calix[4]arene as an intramolecular excimer-forming Na+ sensor in nonaqueous solution

Abstract

A n e w fluorescent calix[4]arene 2 has been synthesized as an intramolecular excimer-forming Na+ sensor which shows a change in fluorescent characteristics specifically upon complexation w i t h Na+.

Effective fluorescent sensing of Na+ ion by calix[4]arene bearing pyrene and perylene based on energy transfer

“…The excimer emission of 4 must be intramolecular excimer emission, because only the pyrene monomer emission was observed by the excitation of 2 having one pyrene moiety at the concentration of 2.0 µM. The calixarene derivatives bearing two pyrene groups on the lower rim have been reported to display monomer emissions from 370-425 nm and excimer emissions at around 480 nm, 18,19 while compound 4 showed a monomer emission from 380-460 nm and excimer emission at 520 nm. This result is presumably attributed to the effect of the electron-withdrawing carbonyl group.…”

“…[7][8][9][10][11][12][13][14][15][16][17] Several groups have recently reported the fluorometric detection of Na + using the calix [4]arene derivatives bearing pyrenyl groups. On these calix [4]arene-based fluorescence sensors, Na + complexation can be monitored by intramolecular pyrene excimer emission and extinction, 18,19 disruption of the intramolecular photoinduced electron transfer from the pyrene to nitrobenzene, 20 and induction of the intramolecular fluorescence energy transfer from the pyrene to anthracene. Perylene exhibits a more intense fluorescence than pyrene, and the fluorescence emission band of perylene significantly overlaps with the absorption band of pyrene.…”

N-Anthracenylmethyl Calix[4]azacrowns as New Fluorescent Ionophores

“…Under a nitrogen atmosphere, treatment with 9-bromo-10-bromomethylanthracene and triethylamine in THF for 48 h reflux led to 1,3-alternate 1 and 2 in 44% and 54% yield, respectively. According to the presence of a singlet peak at around 3.8 ppm in the 1 H NMR as well as the presence of a single peak at 38 ppm in the 13 C NMR spectra, the compounds 1 and 2 were confirmed to maintain the 1,3-alternate conformations. Actually, bromination at 9-position of the anthracene was not intended to be carried out.…”

“…11,12 From this point of view, it is possible that the combination of N-fluorescent azacrown ether and calixcrown ether would result in an optimized structure for metal ion encapsulation due to (I) electrostatic interactions between the metal ion and both the oxygens and a nitrogen as electron donors and (II) π-metal interactions between the metal ion and two rotated aromatic nuclei of the 1,3-alternate calixarene. 13 Dabestani reported that 9-cyanoanthracene armed-1,3-alternate conformer of calix [4]bis-obenzocrown-6 showed a selective binding for Cs + ion. In the absence of cesium ions, fluorescence is partially quenched by photo-induced electron transfer (PET) from the dialkoxybenzene moiety of the crown ring to the excited singlet state of 9-cyanoanthracene.…”

Chloride Selective Calix[4]arene Optical Sensor Combining Urea Functionality with Pyrene Excimer Transduction

“…Pyrenes are a particularly elegant basis for ratiometric based optical sensors, where the ratio of two emission wavelengths comprise the analytical signal 57,58 . To date the pyrene Excimer/monomer system has been exploited mainly for cation sensing [59][60][61][62][63][64][65][66][67][68][69][70] and increasingly for anion sensing [71][72][73][74] . To the best of our knowledge there are few examples where pyrene and (thio)urea systems have been proximally combined in anion host compounds and none based on a calixarene platform 75,76 .…”