Two indole chalcone derivatives as chemosensor for cyanide anions

• Published in: Materials chemistry and physics 2017-01, Vol.186, p.295-300
• Main Authors: Shan, Yanyan, Wu, Qianqian, Sun, Ning, Sun, Yunhui, Cao, Duxia, Liu, Zhiqiang, Guan, Ruifang, Xu, Yongxiao, Yu, Xueying
• Format: Article
• Language: English
• Subjects: Absorption spectra; Acetophenone; Anions; Bromine; Chalcone derivative; Chemical bonds; Chemical reactions; Chemical synthesis; Chemosensor; Color; Condensation; Cyanide anion; Cyanides; Derivatives; Doppler effect; Fluorescence; Hydrogen bonding; Hydrogen bonds; Michael reaction; Reaction mechanisms; Red shift
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2016.10.056

Two bromine substituted indole chalcone derivatives were synthesized via typical condensation reaction between 2-(hydroxyl)-4-bromine acetophenone and 3-indolealdehyde (1) or N-ethyl-3-indolealdehyde (2) in good yields. Their recognition properties for cyanide anions were investigated. The results indicate that the compounds exhibit quick and obvious color and fluorescence turn-on changes to cyanide anions with color changes from yellow to red (1) or from light yellow to deep yellow (2). Mechanism studies suggest that hydrogen bonding reaction between cyanide anions and NH moiety of compound 1 occurs, which leads to the red shift of absorption spectra and the deepening of color. To compound 2, bonding mechanism is typical Michael reaction mechanism. [Display omitted] •Two bromine substituted indole chalcone derivatives were synthesized.•The compounds exhibit fluorescence turn-on response to cyanide anions.•Bonding mechanism of indole compound hydrogen bonding reaction between CN− and NH.•Bonding mechanism of the corresponding N-ethylindole compound is Michael reaction.