Synthesis, complexation, and E—Z photoisomerization of azadithiacrown-containing styryl dyes as new optical sensors for mercury cations

Abstract

New styryl dyes containing azadithia 15 crown 5 fragments were synthesized. The com plexation of these compounds with Ag + , Pb 2+ , Cu 2+ , Hg 2+ , and H + cations was studied by 1 H NMR spectroscopy, steady state, and time resolved spectroscopy. The stability constants of the complexes were calculated from the spectrophotometric titration data. The photophysical properties and E-Z photoisomerization of styryl dyes and their complexes with mercury and copper(II) cations in acetonitrile were examined.A considerable progress in chemistry of macrocyclic compounds is associated not only with their fundamental importance but also with their practical applications in organic synthesis, biology, medicine, and industry. 1-5 Macroheterocyclic sulfur containing compounds (crown compounds, cryptands, catenanes, rotaxanes, and cyclo phanes) have attracted great interest 6-11 because of their ability to selectively form stable complexes with transition and heavy metal cations. These compounds are of consid erable interest as by products in the synthesis of polymers containing thiacrown groups, selective chromogenic and photochromic reagents for metal cations, and extractants for metal salts.The aim of the present study was to synthesize de rivatives of azathiacrown ethers having affinity for heavy and transition metal cations, investigate the complex ation of metal cations with different heteroatoms of the macrocycle, and reveal the influence of complex ation on the optical and photochemical characteris tics of these compounds. Studies of azacrown contain ing styryl dyes demonstrated 12,13 that complexation with rare earth metal cations leads to shifts in absorp tion spectra as large as 50-70 nm. On the one hand, the compounds synthesized and investigated in the present study contain the ionophoric fragment of the phenylazacrown macrocycle, which gives promise that the complexation with metal cations will result in a large optical response. On the other hand, the introduction of sulfur atoms into the macrocycle makes it possible to achieve selective binding with metal salts, which is of

Supramolecular tuning of energy transfer efficiency and direction in a bis(styryl) dye–crown ether conjugate

“…1, Table 1). Comparison with the absorption spectra of the related monochromophoric dyes 2 (λ abs = 395 nm) [18] and 3 (λ abs = 474 nm) [19] in acetonitrile, respectively (Figs. S3 and S4, ESI), allowed to as sign the band at 420 nm to the benzocrown substituted styryl chro mophore of dye 1 and the band at 486 nm to the azadithiacrown sub stituted one.…”

Recent Developments in G-Quadruplex Probes

“…Distyryl Dyes. Distyryl dyes have found use for the construction of sensors for a wide range of analytes, including amyloid protein (Li et al, 2004), mercury ions (Tulyakova et al, 2007), and hydrogen peroxide (Zhan et al, 2010). The styryl scaffold can be easily prepared via the condensation reaction between aldehydes and pyridinium salts.…”

Multimodal Metal Cation Sensing with Bis(macrocyclic) Dye

“…The 4'-formylbenzo-15-crown-5 and 4'-formylphenyl-azathia-15-crown-5 ether precursors were prepared according to reported procedures. [11] Treatment of 2,4-dimethylpyridine at the 4-position by the 4'-formylbenzo-15-crown-5 ether derivative in the presence of tBuOK, followed by alkylation with methyl 4-toluene sulfonate and coupling of the 2-methyl function with 4'-formylbenzo-15-crown-5 ether afforded bisA C H T U N G T R E N N U N G (styryl) dye 1 in a 19 % overall yield as a pure E,E isomer.…”