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A colorimetric probe N,N’-bis(2-methoxy-ethyl)-2,3,3-trimethyl-3H-squaraine (MOESQ) with H2O solubility was synthesized to detect Cu2+. MOESQ exhibits good selectivity, high sensitivity and fast UV-Vis response toward Cu2+ over other competing ions in CH3CN. The detection limit of MOESQ for Cu2+ in CH3CN can reach 1.88 × 10−7 molL−1. By adsorbing MOESQ on the chromatography paper, a colorimetric test paper for Cu2+ was prepared, which could detect Cu2+ with the color change from blue to faint yellow even in the limit of detection concentration of 10−6 molL−1.

Excess tosyl chloride used in the tosylation of alcohols is quickly and easily removed by reacting it with cellulosic materials, e.g., filter paper, and filtering.

An efficient AcO− sensor L which contains 1,10-phenanthroline-based and nitrophenylhydrazine-based groups, and its water-soluble Ru(II) complex were synthesized, characterized and studied in this Letter. Via UV–vis experiments and 1H NMR titration in DMSO solution, it was found that there were potential hydrogen bonds between the N CH and AcO− after the deprotanation of two –NH during the reaction of L or its Ru complex with anions. Furthermore, an easy-to-prepare test paper was developed to detect AcO− at 10 mg/L in pure aqueous solution.

Irradiation of tetrahydrofuran solutions of quinone methide 1 at 350 nm resulted in the formation of yellow oligomeric products and guaiacol. The rate constants determined for the disappearance of the starting compound and those of guaiacol formation show that the primary reaction involves homolysis of the C-O bond between the allylic carbon atom and the oxygen of the phenolic group. (C) 2002 Elsevier Science Ltd. All rights reserved.

Nematodes are parasitic organisms that cause significant damage to crops. Tioxazafen (Nemastrike®), is a proprietary seed treatment being developed by Bayer AG as a broad-spectrum nematicide. Thiophene-2-carbonyl chloride (TCC) is the key raw material in the manufacture of tioxazafen. Current manufacturing routes to TCC suffer from byproduct formation and significant waste generation, which leads to high manufacturing cost. A potentially more cost-effective process for preparing TCC from commercial thiophene has been developed. The advantages of this new chemical approach are illustrated in the processing details described in this Letter.

All claims in the paper cited (Tetrahedron Lett. 3249 (1979)) should be accepted as fact after, but not before, verification by independent experiment.

This Letter aimed to develop an efficient method for the determination of cyanide ion (CN − ). A novel colorimetric chemosensor 4-[(1 E )-2-(4-hydroxyphenyl)ethenyl]-1-allylpyridinium bromide (HPEAPB) was synthesized. HPEAPB displayed good selectivity toward CN − over other competing anions in ethanol. A color change from yellow to red was immediately observed upon the addition of CN − and the limit of detection (LOD) was 3.4 × 10 −6 mol L −1 . The sensing mechanism was discussed by UV–vis, 1 H NMR titration, and a comparison study. Colorimetric test paper for CN − was prepared by attaching HPEAPB to a chromatography paper, which could be used to detect CN − in environmental samples as simply as a pH-indicator paper for pH value. The LOD of the test paper for CN − was 2.0 × 10 −4 mol L −1 . This detection method for CN − has potential applications in cyanide ion containing fields by combination of rapid and real-time advantages.

A new chemosensor based on pyrylium salt has been developed. The sensor can selectively fulfill the detection of lysine among 20 common amino acids in aqueous environment and exhibit a distinct color change and ‘turn-on’ fluorescence. Besides, simple test paper based on this sensor was also presented, which elucidated the feasibility of lysine detection in real samples.

For the first time, we have successfully performed the Henry reaction in neat ‘ Natural Feedstock Extract ’ at room temperature. Herein, we used two most abundant natural feedstock extracts such as ‘ Water Extract of Banana ’ (WEB) and ‘ Water Extract of Rice Straw Ash ’ (WERSA). This protocol is highly advantageous owing to the employment of natural feedstock as green reaction media resulting in significant novelty and advancement with respect to green and sustainable chemistry.

Rhodamine hydrazide-based chemosensors that can detect volatile acidic gases in solid state have been developed. The rhodamine hydrazide probes adsorbed on filter paper respond fluorescently and colorimetrically only to volatile acidic gases but not to organic bases nor to other volatile organic compounds (VOCs). Diethyl chlorophosphate (DCP), one of model compounds used for the studies of Chemical Warfare Agent (CWA), could also be detected by using this method.

In order to establish the tosylated positions of α- and β-cyclodextrins, 13 C-nmr spectra for the monotosyl-derivatives prepared in an alkaline aqueous solution were examined and determined to be in the 6-position of one glucose unit for β-cyclodextrin and to be in the C-2 position for α-cyclodextrin.

As one of the important industrial chemicals, hydrazine (N 2 H 4 ) can be inhaled through the skin, leading to many serious health issues. In this paper, we constructed a novel turn-on fluorescent probe HBTM for N 2 H 4 detection based on ESIPT and ICT mechanism by incorporating the methyl dicyanvinyl group to 2-(2′-hydroxylphenyl) benzothiazole (HBT) fluorophore. The probe showed the following advantages: high sensitivity with detection limit of 2.9 × 10 −7 M, high selectivity over other related interfering species, wide linear range of 0–140 μM and pH value adaptation. Moreover, the probe could detect N 2 H 4 on paper strips and image N 2 H 4 in living cells.