{"title":"Synthesis and photophysical properties of 3-aryl-2-cyanoacrylamides: Design of a turn-on fluorescent probe for cyanide ion detection","authors":"","doi":"10.1016/j.molstruc.2024.139926","DOIUrl":null,"url":null,"abstract":"<div><p>Three 3-aryl-2-cyanoacrylamide derivatives were synthesised in 71−79 % yields from cheap reagents and mild reaction conditions using the Et<sub>3</sub>N-mediated Knoevenagel condensation of fluorescent arylaldehydes (<em>e.g.</em>, triphenylamine and anthracene) with cyanoacetamide. These dyes' photophysical properties and anions-recognizing behaviour were studied, revealing that the 9-anthracenyl derivative can \"turn on\" fluorescence in cyanide presence, with high selectivity and a detection limit (LOD) of 710 nM. Initially, there is fluorescence quenching by the energy transfer (ET) from the anthracene ring to the 2-cyanoacrylamide moiety due to the non-coplanarity of these fragments and, upon the cyanide addition to Cβ of the receptor unit, the intrinsic fluorescence of anthracene is restored. HRMS and NMR experiments and TD-DFT calculations were performed to confirm the detection mechanism and fluorescence properties of the design chemodosimeter; fluorescent test paper was also used to detect cyanide in an aqueous medium.</p></div>","PeriodicalId":16414,"journal":{"name":"Journal of Molecular Structure","volume":null,"pages":null},"PeriodicalIF":4.0000,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Molecular Structure","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022286024024359","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
Three 3-aryl-2-cyanoacrylamide derivatives were synthesised in 71−79 % yields from cheap reagents and mild reaction conditions using the Et3N-mediated Knoevenagel condensation of fluorescent arylaldehydes (e.g., triphenylamine and anthracene) with cyanoacetamide. These dyes' photophysical properties and anions-recognizing behaviour were studied, revealing that the 9-anthracenyl derivative can "turn on" fluorescence in cyanide presence, with high selectivity and a detection limit (LOD) of 710 nM. Initially, there is fluorescence quenching by the energy transfer (ET) from the anthracene ring to the 2-cyanoacrylamide moiety due to the non-coplanarity of these fragments and, upon the cyanide addition to Cβ of the receptor unit, the intrinsic fluorescence of anthracene is restored. HRMS and NMR experiments and TD-DFT calculations were performed to confirm the detection mechanism and fluorescence properties of the design chemodosimeter; fluorescent test paper was also used to detect cyanide in an aqueous medium.
期刊介绍:
The Journal of Molecular Structure is dedicated to the publication of full-length articles and review papers, providing important new structural information on all types of chemical species including:
• Stable and unstable molecules in all types of environments (vapour, molecular beam, liquid, solution, liquid crystal, solid state, matrix-isolated, surface-absorbed etc.)
• Chemical intermediates
• Molecules in excited states
• Biological molecules
• Polymers.
The methods used may include any combination of spectroscopic and non-spectroscopic techniques, for example:
• Infrared spectroscopy (mid, far, near)
• Raman spectroscopy and non-linear Raman methods (CARS, etc.)
• Electronic absorption spectroscopy
• Optical rotatory dispersion and circular dichroism
• Fluorescence and phosphorescence techniques
• Electron spectroscopies (PES, XPS), EXAFS, etc.
• Microwave spectroscopy
• Electron diffraction
• NMR and ESR spectroscopies
• Mössbauer spectroscopy
• X-ray crystallography
• Charge Density Analyses
• Computational Studies (supplementing experimental methods)
We encourage publications combining theoretical and experimental approaches. The structural insights gained by the studies should be correlated with the properties, activity and/ or reactivity of the molecule under investigation and the relevance of this molecule and its implications should be discussed.