A pillar[5]arene-based side-chain pseudorotaxanes and polypseudorotaxanes as novel fluorescent sensors for the selective detection of halogen ions

A pseudorotaxane and its polypseudorotaxanes formed between pillar[5]arene moieties and noctylpyrazinium cations as novel fluorescent sensors for the selective detection of halogen ions were reported. A collapse of these pillar[5]arene-based pseudorotaxanes and polypseudorotaxanes occurred upon the addition of Cl-, Br-, and I- (tetrabutylammonium salts), respectively, leading to their fluorescence recovery. The fluorescence enhancement of the pseudorotaxane and the polypseudorotaxanes increases in the order of I- < Br- < Cl-, and the differences in fluorescence intensity could be easily distinguished by naked eyes under UV light illumination. (C) 2013 Xiao-Yu Hu and Le-Yong Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.