Coumarin-Spiropyran Dyad with a Hydrogenated Pyran Moiety for Rapid, Selective, and Sensitive Fluorometric Detection of Cyanide Anion.
We synthesized a coumarin-spiropyran dyad with a hydrogenated pyran moiety (2), behaving as an off-on type fluorescent receptor for rapid, selective, and sensitive detection of cyanide anion (CN(-)) in aqueous media. The receptor itself shows almost no fluorescence with a quantum yield < 0.01, due to the delocalization of π-electrons over the molecule. Selective nucleophilic addition of CN(-) to the spirocarbon of the molecule rapidly promotes spirocycle opening within only 3 min. This leads to localization of π-electrons on the coumarin moiety and exhibits strong light-blue fluorescence at 459 nm with very high quantum yield (0.52). As a result of this, the receptor facilitates rapid, selective, and sensitive fluorometric detection of CN(-) as low as 1.0 μM.
Research Center for Solar Energy Chemistry, and Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , Toyonaka 560-8531, Japan.|PRESTO, JST, Saitama 332-0012, Japan.
Yasuhiro
Y
Shiraishi
Research Center for Solar Energy Chemistry, and Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , Toyonaka 560-8531, Japan.
Masaya
M
Nakamura
Research Center for Solar Energy Chemistry, and Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , Toyonaka 560-8531, Japan.
Naoto
N
Hayashi
Research Center for Solar Energy Chemistry, and Division of Chemical Engineering, Graduate School of Engineering Science, Osaka University , Toyonaka 560-8531, Japan.
Takayuki
T
Hirai