Spiropyran as a Selective, Sensitive, and Reproducible Cyanide Anion Receptor

Abstract

A spiropyran derivative (1) behaves as a selective and sensitive cyanide anion receptor in aqueous media under UV irradiation. The receptor can be reproduced just by irradiation with visible light.

Molecular switches as photocontrollable “smart” receptors

“…4a). [73][74][75] Compound 45a is an example. The formation of the spiropyran-CN À adduct 45c is detected in a water/acetonitrile solution, after UV irradiation of 45a, as the solution turned from pink, which confirms the formation of the merocyanine 45b, to yellow accompanied by the appearance of an intense absorption band in the visible region with maximum intensity at 421 nm ( Fig.…”

Novel salicylaldehyde derivatives as fluorescence turn-on sensors for cyanide ion

“…It is however wildly used (1.5 million tons per year) and its poisoning may occur in particular receptors include borane [12,13], indolium [14,15] and hydrogenbonded carbonyl compounds [16,11], many of which are related to the reduction of intramolecular charge transfer (ICT) process. The ICT process is situated in a -conjugated molecular system consisting of electron donating and accepting groups [17][18][19][20].…”

Antibacterial Drug Releasing Materials by Post-Polymerization Surface Modification

“…8 The development of drug delivery systems, and in particular the surface delivery of bioactive agents, especially from nanoparticles, [16][17][18][19][20][21] is currently of interest for its obvious medical and hygiene applications [22][23][24] especially in the area of antibacterials 25 ; recent work is noteworthy in that regard. 26,27 Inspiration for the work reported herein came from a report in which small anions were found to bind reversibly with spiropyrans, 28,29 and of interest was whether a similar phenomenon might also bind carboxylates, and therefore penicillin, which would in turn impart bactericidal properties to a supporting polymer; the delivery of penicillin from polymers has been reported. 30 Even if such discrete one-to-one binding of carboxylate with spiropyrans did not occur, nonspeci¯c binding resulting from the change in surface polarity from the presence of a spiropyran might have been expected to lead to a similar outcome.…”

“…has been reported (but also see ESI for relevant data) 9,14,34 Reaction of this modi¯ed polymer with the known iodides 5a,b 28,35 then gave the spirocyanine materials 6a,b. The presence of the spiropyran unit on the surface was con¯rmed from the presence of nitro groups in the ATR-IR spectrum of 6a (1510 cm À1 ), and bromo groups in the combustion analysis and XPS spectrum of 6b (see ESI); estimation of the surface loading data from the combustion analysis gave densities of 6:7 Â 10 12 , 5:0 Â 10 12 , 2:7 Â 10 12 and 2:6 Â 10 12 molecules.…”