New Heteropolycyclic Structures for Fluoride Anion Sensing by Naked‐Eye Visualization

Abstract

Fluoride anion (F−) plays an important and fundamental role in chemical, biological, pathological, and environmental processes. It is highly desired to develop new methods for facial and efficient F− detection. Herein we present the synthesis and characterization of two effective fluoride ion probes and their selective F− sensing by naked‐eye visualization. A N‐heteroannelated anthraquinone derivative, compound I, was prepared by a cyclocondensation reaction of 1,2‐diaminoanthraquinone with 1,6‐bis(triisopropylsilyl)‐hexa‐l,5‐diyne‐3,4‐dione. Compound I was treated with malononitrile in the presence of Lehnert reagent to afford an HCl adduct, compound II, and an aza‐polycyclic aromatic compound III. All three compounds were characterized crystallographically and were studied photochemically. Similarly, 2,3‐diamino‐1,4‐anthraquinone reacted with 1,6‐bis(triisopropylsilyl)‐hexa‐l,5‐diyne‐3,4‐dione to afford compound IV, which reacted with malononitrile in the presence of Lehnert reagent to yield compound V. Compounds III and V are sensitive and selective probes for the detection of F− with significant color changes. The detection by naked eye visualization is rapid and facile, showing both compounds are potential probes for fluoride ion sensing.

Crystal structure of 3-[(triisopropylsilanyl)-ethynyl]-6a,12a-dihydro-1H-1,4-diaza-benzo[α]anthracene-2,7,12-trione, C27H28N2O3Si

“…This is probably due to steric effects from the bulky triisopropylsilyl group. Angles and bond lengths fall in their normal ranges compared with previously studies [9,10].…”

Clean Preparation of Quinolin-2-yl Substituted Ureas in Water

“…According to previous reports, the C2 position of quinoline N -oxides may be functionalized via a number of reaction processes, which include the C–H bond alkylation, − arylation, alkenylation, − acetoxylation, , sulfonylation, − amidation, − amination, − hydroxylation, , phosphonation, , and thiolation of quinoline N -oxides. However, to the best of our knowledge, the preparation of quinolin-2-yl substituted ureas from readily available quinoline N -oxides has never been reported.…”

A π‐Conjugated Chromophore Dye and Its Functional Paper Strips for Visually On‐Site Sensing F− and Its Reaction Mechanism

“…Accordingly, colorimetric chromophore with special receptor is routinely applied for quantitative or qualitative determination of different analytes in practice. For fluoride ion (F − ), the smallest size and highest charge density, any chronic deficiency of F − will lead to gastric and kidney disorder or osteoporosis, while excess F − would induce dental and skeletal fluorosis and other serious diseases including collagen breakdown, bone disorders and immune system disruption . Great efforts have been devoted for F − detection, such as chromatography, electrochemistry, photoluminescence, mass spectrometry,, fluorescent spectrophotometry and colorimetric spectrophotometry .…”