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In this study, the reaction between 2-(3,5-dimethylpyrazolylmethyl)-5-(dimethylaminomethyl)pyrrole and thiophenol under heating conditions afforded the new ligand 2-(3,5-dimethylpyrazolylmethyl)-5-(phenylthiomethyl)pyrrole 2. The reaction of 2 with meta-chloroperbenzoic acid provided sulfoxide 3 and sulfone 4 group-containing ligands. The reaction of 2 with copper(I) halides provided the binuclear complexes [Cu(μ-X){μ-C4H3N-2-(CH2Me2pz)-5-(CH2SPh)-κ2-S,N}]2 (X = Cl, Br and I, 5–7) in high yields. Conversely, the analogous reaction of 4 with copper(I) halides yielded two types of complexes, three coordinate bi- and mononuclear of the type [Cu(μ-Cl){C4H3N-2-(CH2Me2pz)-5-(CH2SO2Ph)-κ1-N}]28 and [CuX{C4H3N-2-(CH2Me2pz)-5-(CH2SO2Ph)-κ1-N}2], X = Br, 9 and I, 10. When the reaction was carried out in the presence of KPF6, the two-coordinate complex [Cu{C4H3N-2-(CH2Me2pz)-5-(CH2SO2Ph)-κ1-N}2]PF6−11a was isolated, whereas its BF4− analogue 11b was synthesized by the reaction of 8 with AgBF4. The structures of these complexes were determined using single-crystal X-ray crystallography. These copper complexes catalyzed the hydroamination–alkynylation reaction between several secondary amines and alkyl and aryl terminal alkynes. Using 1 mol% of complexes 5–10 as catalysts, both tri- and tetra-substituted propargylamines were isolated. Alternatively, phenylacetylene and different secondary amines afforded the corresponding trisubstituted propargylamines as the major products and alkyl terminal alkynes gave the tetrasubstituted products in excellent yields. In addition, the role of counter anions such as TfO−, PF6−, BF4−, PO43− and Ph4B− on the product selectivity was studied. When fluorinated anions such as TfO−, PF6−, and BF4− were present with the copper complexes, the hydroamination–hydrovinylation product 1-aminodiene 23 was observed, which was not formed with PO43−, Ph4B− or halide ions. Specifically, TfO− and PF6− favored the formation of 23, while BF4− favored the tetrasubstituted product as the major product. This was further supported by the isolated copper(I) complexes containing PF6− and BF4− and by other specific reactions. The peaks for enamines and [LCu]+ species in the HRMS spectra of the reaction mixtures and the isolation of the morpholinium copper(I) salt support the proposed mechanism. [ABSTRACT FROM AUTHOR]

In order to specifically demonstrate the improvement of photocatalytic activity attributed to the donor‐acceptor (D‐A) structure rather than other contributing factors, two highly comparable COFs incorporating porphyrin and thiophene species are synthesized in this work. The first COF, named BTDA‐Por, is composed of porphyrin (Por) as the donor unit and 2,2′‐bithiophene (BTDA) as the acceptor moiety. The second COF, referred to as TT‐Por, is constructed using Por and thieno[3,2‐b]thiophene (TT) units while lacking a D‐A structure. These synthesized COFs serve as effective models for investigating the role of D‐A structures in improving photocatalytic activity. Photoelectronic property studies and density function theory calculations indicate that the D‐A configuration can significantly enhance the efficiency of charge carrier generation, separation, and migration. Consequently, the D‐A type BTDA‐Por exhibits superior performance in photochemical reactions such as oxidative homocoupling of aromatic amine and reversible complexation‐mediated radical polymerization when compared to the non‐D‐A type TT‐Por. [ABSTRACT FROM AUTHOR]

Primary aromatic amines (PAAs) may be found in food contact materials and can potentially migrate from packaging material into the packed foodstuffs. Certain members of this substance class are of particular concern due to their toxicological properties. Legislators and authorities require a risk assessment regarding the transfer of PAAs into food. The evaluation of PAAs' migration into food relies on migration or extraction tests using aqueous and acidic food simulants or solvents. However, PAAs exhibit stability issues in acidic media, which could lead to an underestimation of migration. Therefore, a systematic stability study was conducted for 28 PAAs in 3% acetic acid and water at different storage conditions. Standard solutions of 2 and 10 ng/ml of the amines in these media were prepared and stored under the following conditions: 2 h at 40 °C, 70 °C, and 100 °C, and 10 days at − 20 °C, 4 °C, 20 °C, 40° C, and 60 °C. The test solutions were analyzed using liquid chromatography coupled to mass spectrometry, and recovery was calculated against freshly prepared standard solutions. It was found that several PAAs undergo a loss of recovery under the investigated conditions; 7 of the substances were identified to be the most unstable: 3,3ʹ-dimethoxybenzidine, 3,3ʹ-dimethylbenzidine, 6-methoxy-m-toluidine, 4-methoxy-m-phenylendiamine, 2,6-toluenediamine, benzidine and 2,4-toluenediamine. It was concluded that both time and storage temperature play a pivotal role in the stability of PAAs. The experiments also demonstrated that PAAs exhibit greater stability in water than in 3% acetic acid. [ABSTRACT FROM AUTHOR]

The utilization of two‐component systems comprising camphorquinone (CQ) and aromatic amines has become prevalent in the photopolymerization. However, there are still concerns about the safety of this CQ/amine system, mainly because of the toxicity associated with the leaching of aromatic amines. In light of these concerns, this study aims to develop novel coinitiator combinations featuring CQ and amines which cannot be leached out of materials, enabling free radical polymerization of representative dentalmethacrylate resins under blue light irradiation. This approach involves the initial design and analysis of hydrogen donors with low C─H bond dissociation energy through molecular modeling. Subsequently, copolymerizable methacrylate functional groups are incorporated via chemical modification, allowing it to act as both coinitiator and copolymerization monomer to achieve low migrationand leachability properties. This work presents, for the first time, the synthesis of the innovative coinitiator and compares its performance with the benchmark CQ/ethyl‐4‐dimethylaminobenzoate (EDB)‐based photoinitiation system (PIS). The results demonstrate the effectiveness of the newly proposed PIS. Finally, an in‐depth investigation is conducted into the reaction mechanism associated with this PIS through molecular orbital calculations and electron spin resonance studies. [ABSTRACT FROM AUTHOR]

Intercalation chemistry is pivotal in discovering the dimension-dependent properties of 2D materials and expanding their applications. Layered bismuth oxide with composition Bi 0.775 Ln 0.225 O 1.5 (Ln = La, Pr, Nd, Sm, and Eu) has been demonstrated to intercalate both aliphatic and aromatic amines, resulting in the unit cell expansion along the c -axis. Aliphatic amines were present in a vertical orientation, whereas aromatic amines preferred a horizontal orientation. The intercalated amine concentrations ranged from 0.15 to 0.54 mole per mole of the host. Among the chosen amines, ethylenediamine intercalation enhanced the c -axis of Bi 0.775 Pr 0.225 O 1.5 by 20 Å, justified by the high amounts of intercalant and intermolecular hydrogen bonding between them, resulting in a bilayer arrangement. The lamellar-plate-like morphology filled with intercalants and twinning collapse was noticed in the FESEM and SAED patterns after the intercalation process. The ethylenediamine intercalated Bi 0.775 Pr 0.225 O 1.5 was further evaluated for iodine adsorption from non-aqueous solutions through chemisorption following pseudo-second-order kinetics. The X-ray diffraction peaks after adsorption suggested bilayer to monolayer transformation aided by chemical alterations within the host's van der Waals gaps. The N–I vibration mode, observed in the FTIR spectrum of the iodine-adsorbed sample, further augmented the interaction between the two during adsorption. [ABSTRACT FROM AUTHOR]

Aromatic amines are important commercial chemicals, but their carcinogenicity poses a threat to humans and other organisms, making their rapid quantitative detection increasingly urgent. Here, amorphous MoO3 (a‐MoO3) monolayers with localized surface plasmon resonance (LSPR) effect in the visible region are designed for the trace detection of carcinogenic aromatic amine molecules. The hot‐electron fast decay component of a‐MoO3 decreases from 301 fs to 150 fs after absorption with methyl orange (MO) molecules, indicating the plasmon‐induced hot‐electron transfer (PIHET) process from a‐MoO3 to MO. Therefore, a‐MoO3 monolayers present high SERS performance due to the synergistic effect of electromagnetic enhancement (EM) and PIHET, proposing the EM‐PIHET synergistic mechanism in a‐MoO3. In addition, a‐MoO3 possesses higher electron delocalization and electronic state density than crystal MoO3 (c‐MoO3), which is conducive to the PIHET. The limit of detection (LOD) for o‐aminoazotoluene (o‐AAT) is 10−9 M with good uniformity, acid resistance, and thermal stability. In this work, trace detection and identification of various carcinogenic aromatic amines based on a‐MoO3 monolayers is realized, which is of great significance for reducing cancer infection rates. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Chemical Communications" published in 2024. It includes various articles on topics such as bioinspired catalysts, nanoparticle exsolution, metal-organic frameworks, and more. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document provides a brief overview of the articles included in the issue, allowing library patrons to quickly identify relevant research topics. [Extracted from the article]

Photoelectrochemical (PEC) cell is an ideal platform for organic transformation because of its green benefits and minimal energy consumption. As an emerging methodology, the reaction types of photoelectrocatalytic organic synthesis (PECOS) are limited to simple oxidation and C–H activation at current stage. Metal catalysis for the construction of C(sp2)–N bonds has not been touched yet in PECOS. We introduce here a PEC method that successfully engages Ni catalysis for the mild production of aniline derivatives. Experimental and computational investigations elucidate that the addition of photoanode-generated amine radical to Ni catalyst avoids the sluggish nucleophilic attack, enabling the reaction to proceed at an ultra-low potential (–0.4 V vs. Ag/AgNO3) and preventing the overoxidation of products in conventional electrochemical synthesis. This synergistic catalysis strategy exhibits good functional group tolerance and wide substrate scope on both aryl halides and amines, by which some important natural products and pharmaceutical chemicals have been successfully modified. The reaction types of photoelectrocatalytic organic synthesis (PECOS) are limited to simple oxidation and C–H activation at current stage while metal catalysis for the construction of C(sp2)–N bonds remains unexplored. Here, the authors introduce a PEC method that successfully engages Ni catalysis for the mild production of aniline derivatives. [ABSTRACT FROM AUTHOR]

Palladium catalyzed tandem reaction represents a one-pot synthetic approach to efficiently synthesize complex functionalized molecules while reducing synthetic steps, aligning with the principles of green chemistry. However, achieving a direct cascade of the aza-Wacker and Povarov reactions in one-pot synthesis presents a challenge due to substrate compatibility issues between the two reactions. In this work, we describe an aza-Wacker/Povarov reaction employing a highly electrophilic palladium catalyst, which effectively converts anilines and 1,6-dienes into hexahydro-cyclopenta[b]quinolines. The optimized conditions yield up to 79%, with a diastereoselectivity > 20:1. Substrate range testing reveals compatibility with various sensitive functional groups, and successful late-stage modifications are performed on several natural products and drug molecules, demonstrating the versatility and practicality of the method. Additionally, a preliminary investigation into the reaction mechanism suggests an aza-Wacker process followed by a Povarov process. Achieving a direct cascade of the aza-Wacker and Povarov reactions in one-pot synthesis presents a challenge due to substrate compatibility issues between the two reactions. Here, the authors report an aza-Wacker/Povarov reaction of anilines with 1,6-dienes to obtain the hexahydro-cyclopenta[b]quinolines. [ABSTRACT FROM AUTHOR]

Singlet oxygen is a powerful oxidant used in various applications, such as organic synthesis, medicine, and environmental remediation. Organic and inorganic photosensitizers are commonly used to generate this reactive species through energy transfer with the triplet ground state of oxygen. We describe here a series of novel benzophenazine derivatives as a promising class of photosensitizers for singlet oxygen photosensitization. In this study, we investigated the structure‐activity relationship of these benzophenazine derivatives. Akin to a molecular compass, the southern fragment was first functionalized with either aromatic tertiary amines, alkyl tertiary amines, aromatic sulfur groups, alkyl sulfur groups, or cyclic ethers. Enhanced photophysical properties (in terms of triplet excited‐state lifetime, absorption wavelength, triplet state energy, and O2 quenching capabilities) were obtained with cyclic ether and sulfur groups. Conversely, the presence of an amine moiety was detrimental to the photocatalysts. The western and northern fragments were also investigated and slightly undesirable to negligible changes in photophysical properties were observed. The most promising candidate was then immobilized on silica nanoparticles and its photoactivity was evaluated in the citronellol photooxidation reaction. A high NMR yield of 97 % in desired product was obtained, with only a slight decrease over several recycling runs (85 % in the fourth run). These results provide insights into the design of efficient photosensitizers for singlet oxygen generation and the development of heterogeneous systems. [ABSTRACT FROM AUTHOR]

A method for the synthesis of furans bearing indoline skeletons was developed via an intramolecular palladium-catalyzed 5-exo-dig cyclization/etherification cascade of N-propargyl arylamines containing a 1,3-dicarbonyl side chain. This method realized the first capture of vinyl carbopalladiums by ketones as O-nucleophiles and showed a wide range of substrate tolerability affording trisubstituted furans in various yields. The enantioselective version for this domino process and diverse derivatizations of the reaction products were also studied. [ABSTRACT FROM AUTHOR]

Ebselen (EbSe), a therapeutically significant molecule, is shown to exhibit chalcogen bonding interaction with nitrite anion (ONO−). This report suggests that the σ-holes of EbSe are powerful for offering weak but influential interactions towards biologically relevant ONO−, thereby assisting oxidative transformations like N-nitrosation of aromatic amines. [ABSTRACT FROM AUTHOR]

We have developed a one-pot, four-component synthetic approach utilizing 5-sulfosalicylic acid dihydrate (5-SSA.2H2O) as an organocatalyst, enabling the synthesis of polyfunctional 3-pyrrolin-2-one molecules by employing dialkylacetylenedicarboxylate, amines, and either formaldehyde or aromatic aldehydes at room temperature. This approach presents numerous notable benefits such as shorter reaction time, simple and eco-friendly procedure, excellent yield, broad applicability across various substrates, and the use of a cost-effective, easily accessible and biodegradable catalyst. The structures of the 3-pyrrolin-2-one molecules were confirmed using techniques such as FTIR, 1HNMR, 13CNMR and HRMS. Overall, this study demonstrates a promising method for producing environmentally friendly polyfunctional 3-pyrrolin-2-one efficiently and smoothly at ambient temperature. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Herein, we present a method for the homogeneous hydrogenation of nitroarenes to produce anilines using low catalyst loading (1 mo%) of copper N‐heterocyclic carbene complexes as the catalyst and ammonia borane as the source of hydrogen. A wide range of nitroarenes, featuring diverse functional groups, were selectively transformed into their corresponding primary aromatic amines with high yields. This process can be readily scaled up and exhibits compatibility with various sensitive functional groups, including halogen, trifluoromethyl, aminomethyl, alkenyl, cyano, ester, amide, and hydroxyl. Notably, this catalytic methodology finds application in the synthesis of essential drug compounds. Mechanistic investigations suggest that the in‐situ‐generated Cu‐H species may serve as active intermediates, with reduction pathways involving species such as azobenzene, 1,2‐diphenylhydrazine, nitrosobenzene, and N‐phenylhydroxylamine. [ABSTRACT FROM AUTHOR]

This article presents a comprehensive organic chemistry experiment in which salicylaldehyde, phenylboronic acid, and aromatic amines are employed as the substrates. The selective synthesis of diarylmethyl aniline and triarylmethane could be achieved through the control of substituents. The structure of the product is characterized by ¹H NMR and 13C NMR. This experiment combines theoretical knowledge to inspire students to think about mechanisms, helps them broaden their knowledge horizons, and establishes the concept of "green chemistry" and environmental awareness. [ABSTRACT FROM AUTHOR]

BACKGROUND: The present research was conducted to investigate the impact of reishi mushroom extract (RME) on the formation of heterocyclic aromatic amines (HAAs) in meatballs. Sample preparations involved applying RME using either the spreading or addition method, with varying concentrations (0%, 0.25%, 0.5%, and 1% of RME), followed by deep‐frying at temperatures of 150 and 190 °C for 3 min. RESULTS: The types and levels of HAAs varied based on the frying temperature, method of extract application, and the extract concentration. Notably, total HAA contents increased with rising the frying temperature (P < 0.01) and varied from undetectable levels to 4.91 ng g−1 across all analyzed meatballs. The addition method was more effective than the spreading method (P < 0.01), and among the concentrations tested 0.25% RME exhibited the highest efficacy in reducing total HAAs (P < 0.05). Furthermore, the addition method inhibited lipid oxidation more efficiently compared to the surface spreading method (P < 0.05). CONCLUSION: This study demonstrated that RME had mitigating effects on HAAs depending on the concentration and frying conditions in deep‐fried meatball samples. © 2024 The Author(s). Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The reduction of CO2 is an important method to produce chemicals such as methanol, formic acid, formaldehyde, etc. In general, the reduction of CO2 is carried out at high temperatures and pressures with precious metals as catalysts, which is not favorable for industrial procedures. Thus, it will be very useful if researchers can find cost-effective catalysts for industrial application in CO2 reduction. In this work, commercially available ethylenediaminetetraacetic acid (EDTA) was tested as a cheap, non-toxic, and recyclable catalyst to initiate the N-carbonylation reaction of CO2 with amines. After screening various reaction parameters, including temperature, pressure, time, solvent, and reducing agent, the optimal reaction conditions were obtained: 80 °C, 2 MPa, 6 h, 50 mmol% catalyst dosage, 1 mL DMSO, and 1:1 molar ratio of amine to reducing agent. Notably, further studies confirmed that EDTA could also be effective for N-formylation even under ambient conditions (0.1 MPa and room temperature). The suitability of the catalyst for 26 kinds of substrates (including aliphatic amines, aromatic amines, and alicyclic amines) and its reusability were also investigated, with satisfactory results. Scale-up research has been performed effectively with a high conversion of amine (83%) to obtain the mono-formylated product selectively. Finally, the mechanism of the reaction between amine and CO2 has been proposed via control experiments and compared with results in the literature. [ABSTRACT FROM AUTHOR]

Atropisomers hold significant fascination, not only for their prevalence in natural compounds but also for their biological importance and wide‐ranging applications as chiral materials, ligands, and organocatalysts. While biaryl and heterobiaryl atropisomers are commonly studied, the enantioselective synthesis of less abundant heteroatom‐linked non‐biaryl atropisomers presents a formidable challenge in modern organic synthesis. Unlike classical atropisomers, these molecules allow rotation around two bonds, resulting in low barriers to enantiomerization through concerted bond rotations. In recent years the discovery of new configurationally stable rare non‐biaryl scaffolds such as aryl amines, aryl ethers and aryl sulfones as well as innovative methodologies to control their configuration have been disclosed in the literature and constitute the topic of this minireview. [ABSTRACT FROM AUTHOR]

Biocatalysis provides an attractive approach to facilitate synthetic reactions in aqueous media. Motivated by the discovery of promiscuous aminolysis activity of esterases, we exploited the esterase from Pyrobaculum calidifontis VA1 (PestE) for the synthesis of carbamates from different aliphatic, aromatic, and arylaliphatic amines and a set of carbonates such as dimethyl‐, dibenzyl‐, or diallyl carbonate. Thus, aniline and benzylamine derivatives, aliphatic and even secondary amines could be efficiently converted into the corresponding benzyloxycarbonyl (Cbz)‐ or allyloxycarbonyl (Alloc)‐protected products in bulk water, with (isolated) yields of up to 99 %. [ABSTRACT FROM AUTHOR]

As the global production of polymers exceeded 400 million tons in 2022, it is imperative that recycling rates are increased to prevent the predominant end-of-life handling through landfilling and incineration processes. With an increasing reliance on polyurethane (PU), the 2022 global production of PU reached almost 26 million tons. As PU is mainly utilised as a thermoset material, the extensive cross-linked networks render melting and remolding processes known from thermoplastic materials incompatible. As such, the majority of PU that is recycled is processed through mechanical shredding and gluing processes or chemical recycling via glycolysis and acidolysis processes for polyol recovery, all providing a secondary material with properties different from the parent material. Here, we show that the well-established acidolysis process can be used to both depolymerise PU and separate the polyol and dianiline adducts with a specific focus on analysing and valorising the dianiline component arising from the hard segment of PU. By evaluation of the reaction outcome from acidolysis of flexible PU foam with succinic acid, adipic acid or phthalic acid under neat conditions, succinic acid was found to form the corresponding succinimide of toluene diamines that is readily separable from the polyol. The toluene diamine could in turn be reformed through ruthenium-catalysed hydrogenation or simple hydrolysis. Ultimately, the combined acidolysis/hydrolysis of a flexible PU foam yields the polyol and dianiline in a combined 83 wt% recovery. A similar recovery rate was achieved for a commercial rebonded flexible foam. As current PU recycling methods only target the polyol fraction often obtained in a low quality, this advancement shows that current industrially applied acidolysis could be altered so that both the diamines and polyol can be obtained from flexible PU foam. Preliminary results show that the process is applicable to rigid PU foams, a PU fraction that is difficult to recycle due to its molecular complexity. Finally, a mechanistic pathway is suggested to account for the observed product distributions. [ABSTRACT FROM AUTHOR]

A copper‐catalyzed one‐pot three‐component aminophosphinoylation reaction of 1,4‐naphthoquinone with disubstituted phosphine oxides and arylamines has been developed. Various disubstituted phosphine oxides and arylamines with diverse structures and electronic properties can work smoothly with 1,4‐naphthoquinone, afforded a series of corresponding aminophosphinoylated 1,4‐naphthoquinones with up to 96 % isolated yield. The present method features easily available reagents, operational simplicity, broad substrate scope, high atom and step economy. The potential practicality of this protocol was further demonstrated by gram‐scale synthesis. [ABSTRACT FROM AUTHOR]

This work describes a novel iron‐catalysed approach for the synthesis of aryl‐substituted benzimidazoles and benzoxazoles. The methodology employs reductive carbonylation using readily available aryl iodides and aryl amines as precursors, with carbon monoxide serving as the efficient carbonyl source. The reaction proceeds under mild conditions with the addition of hydrosilanes and bases. Notably, aryl aldehydes are generated in situ from the aryl iodides, which subsequently react with o‐phenylenediamine or 2‐aminophenol to afford the desired products in high yields. The structures of the synthesized benzimidazoles and benzoxazoles were confirmed using 1H and 13C NMR spectroscopy and mass spectrometry. [ABSTRACT FROM AUTHOR]

A novel process using N-benzylhydroxylamine hydrochloride as a "C1N1 synthon" in [2+2+1] cyclization for the construction of 1,2,5-trisubstituted imidazoles has been described for the first time. The key to realizing this process lies in capturing arylamines by in situ generated novel acyl ketonitrone intermediates. Subsequent tautomerization activates the α-C(sp3)–H of N-benzylhydroxylamines, and thus breaks through its inherent reaction mode and achieves N, α-C site-selective cyclization. Furthermore, this method enables scale-up synthesis and late-stage modification of complex molecules. [ABSTRACT FROM AUTHOR]

Candida albicans is one of the most dangerous pathogenic fungi in the world, according to the classification of the World Health Organization, due to the continued development of its resistance to currently available anticandidal agents. To overcome this problem, the current work provided a simple, one-step, cost-effective, and safe technique for the biosynthesis of new functionalized anticandidal selenium nanoparticles (Se NPs) against C. albicans ATCC10231 using the cell-free supernatant of Limosilactobacillus fermentum (OR553490) strain. The bacterial strain was isolated from yogurt samples available in supermarkets, in Damietta, Egypt. The mixing ratio of 1:9 v/v% between cell-free bacterial metabolites and sodium selenite (5 mM) for 72 h at 37 °C were the optimum conditions for Se NPs biosynthesis. Ultraviolet–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), Zeta analyses, and elemental analysis system (EDS) were used to evaluate the optimized Se NPs. The Se NPs absorption peak appeared at 254 nm. Physicochemical analysis of Se NPs revealed the crystalline-shaped and well-dispersed formation of NPs with an average particle size of 17–30 nm. Se NPs have − 11.8 mV, as seen by the zeta potential graph. FT-IR spectrum displayed bands of symmetric and asymmetric amines at 3279.36 cm−1 and 2928.38 cm−1, aromatic and aliphatic (C–N) at 1393.32 cm−1 and 1237.11.37 cm−1 confirming the presence of proteins as stabilizing and capping agents. Se NPs acted as a superior inhibitor of C. albicans with an inhibition zone of 26 ± 0.03 mm and MIC value of 15 µg/mL compared to one of the traditional anticandidal agent, miconazole, which revealed 18 ± 0.14 mm and 75 µg/mL. The cytotoxicity test shows that Se NPs have a low toxic effect on the normal keratinocyte (IC50 ≈ 41.5 μg/mL). The results indicate that this green synthesis of Se NPs may have a promising potential to provide a new strategy for drug therapy. [ABSTRACT FROM AUTHOR]

An efficient heterogeneous catalytic system for the oxidative aminocarbonylation of alkynes and amines in the presence of CO/O2 to afford substituted propiolamides has been developed. The active nanocatalyst, [Pd/Mg3Al‐LDH]‐300(D), is composed by Pd nanoaggregates (2–3 nm average particle size) stabilized over a partially dehydrated [Mg3Al‐LDH] matrix. The methodology has resulted widely applicable, being the first catalytic system, either homogeneous or heterogeneous, able to activate not only aliphatic amines but also poorly‐nucleophilic aromatic amines. In fact, >60 substituted propiolamides have been synthesized in good to excellent isolated yields through this methodology, being 27 novel compounds. An important characterization effort (XRD, 27Al MAS NMR, TGA, TPD‐CO2, BET area, XPS, HAADF‐HRSTEM and HRTEM) and optimization of the synthesis conditions of the optimal catalyst has been performed. This study, together with a series of kinetic and mechanistic essays, indicates that the optimal catalyst is composed by Pd(0) species stabilized in a partially dehydrated/dehydroxylated LDH material with a Mg/Al molar ratio of 3 and a small crystallite size. All the experimental data indicates that the in situ formation of [PdI2] active species in the material surface together with the presence of a matrix with the optimal acid/base properties are key aspects of this process. [ABSTRACT FROM AUTHOR]

In recent times, the research on the synthesis of highly functionalized piperidines has become a challenge and an attractive research field among synthetic chemists because these compounds have many biological, pharmaceutical and industrial applications. In this regard, in this paper we would like to report a green, rapid and efficient method for the synthesis of highly functionalized piperidines based on the use of zinc (II) chloride supported on Fe3O4 NPs modified with Dopamine and 5H-Cyclopenta[2,1-b:3,4-b′]dipyridin-5-one [Fe3O4@Dop/CP-diPy-ZnCl2 as a novel magnetically reusable catalyst. The structure of Fe3O4@Dop/CP-diPy-ZnCl2 nanocatalyst was well identified by several spectroscopic techniques including: FT-IR, TEM, SEM, EDX, ICP-OES, TGA, XRD, VSM and Elemental mapping technique. One-pot three-component reactions of aromatic amines with different aryl aldehydes and β-ketoesters were performed in water and all desired highly functionalized piperidines were synthesized with high to excellent yields, which indicates the high efficiency of this catalytic system. The reusability tests shown that that Fe3O4@Dop/CP-diPy-ZnCl2 catalyst is a reusable and stable catalyst. [ABSTRACT FROM AUTHOR]

Waterpipe smoking is increasingly popular and understanding how chemicals found in hookah smoke may be harmful to human bronchial epithelial cells is of great importance. 4,4'-Oxydianiline (ODA), is an aromatic amine which is present at comparatively high levels in hookah smoke. The metabolism and the subsequent toxicity of ODA in human bronchial epithelial cells remains unknown. Given that ODA is an aromatic amine, we hypothesized that ODA is N -acetylated and induces DNA damage following exposure to immortalized human bronchial epithelial cells (BEP2D cells). We measured the N -acetylation of ODA to mono-acetyl-ODA and the N -acetylation of mono-acetyl-ODA to diacetyl-ODA by BEP2D cells following separation and quantitation by high performance liquid chromatography. For ODA, the apparent K M in cells was 12.4 ± 3.7 µM with a V max of 0.69 ± 0.03 nmol/min/106 cells, while for mono-acetyl-ODA, the apparent K M was 111.2 ± 48.3 µM with a V max of 17.8 ± 5.7 nmol/min/106 cells ODA exposure for 24 h resulted in DNA damage to BEP2D cells following concentrations as low as 0.1 µM as measured by yH2Ax protein expression These results demonstrate that ODA, the most prevalent aromatic amine identified in hookah smoke, is N -acetylated and induces DNA damage in human bronchial epithelial cells. • 4,4'-Oxydianiline (ODA) is present at comparatively high levels in hookah smoke. • N -acetylation of ODA was determined in human bronchial epithelial cells. • ODA exposure resulted in DNA damage to human bronchial epithelial cells. [ABSTRACT FROM AUTHOR]

One hundred and twenty samples of meat products represented by grilled kofta, grilled meat, charcoal grilled kofta, and charcoal grilled meat (30 pieces each) were randomly collected from different markets in Kalyobia Governorate, Egypt. Each sample was individually packed in a plastic bag and taken directly to the laboratory. Collected samples were analyzed for heterocyclic aromatic hydrocarbons (HAAs). This study aimed to reduce the amount of carbonization and fat pyrolysis by reducing the amount of meat droplets using antioxidants such as butylhydroxytoluene (0.02%) and carvacrol (1%). The observed findings showed that the average levels of HAAs (pg/kg) in charcoal-grilled meat samples, left untreated (n = 30), were as follows: BhIP, MelQx, 4,8-DiMelQx and Norharman were Norharman while IQ was beyond the undetected limit (UDL). Meanwhile, the treated samples with (BHT 0.0% and carvacrol 1%) showed that individuals; BhIP, MelQx, 4,8-DiMelQx, and Norharman were 3.8±0.3, 0.5±0.1, 1.2±0.1 and 1.8±0.1 with reduction percentage 41.5%, 28.6%, 36.8% and 47.1%, respectively for BHT concentration 0.02%. While for carvacrol concentration 1% individuals; BhIP, MelQx, 4,8-DiMelQx, and Norharman were 3.1±0.2, 0.4±0.2, 1.0±0.1 and 1.5±0.1 with reduction percentages 52.3%, 42.9%, 47.4%, and 55.9%, respectively. In conclusion, this study recommends the treatment of charcoal grilled meat with antioxidants, such as BHT 0.0% and carvacrol 1%, to reduce HAAS concentrations in the examined samples. [ABSTRACT FROM AUTHOR]

This document provides information on the synthesis and characterization of various compounds, including β-aminonitriles, β-amino sulfones, and dimethyl aspartates. The compounds were synthesized using lanthanoid triflates Yb(OTf)3 and Tb(OTf)3 as catalysts and the reactions were optimized for yield. The document also includes spectroscopic data, such as melting points and NMR spectra, for the compounds. The data presented in the document match those previously reported in the literature. The document acknowledges the facilities used for the research and dedicates the work to the late Prof. Ibrahim Ibnusaud. [Extracted from the article]

BACKGROUND: Faced with the need to develop new herbicides with modes of action different to those observed for existing agrochemicals, one of the most promising strategies employed by synthetic chemists involves the structural modification of molecules found in natural products. Molecules containing amides, imides, and epoxides as functional groups are prevalent in nature and find extensive application in synthesizing more intricate compounds due to their biological properties. In this context, this paper delineates the synthesis of N‐phenylnorbornenesuccinimide derivatives, conducts biological assays, and carries out in silico investigation of the protein target associated with the most potent compound in plant organisms. The phytotoxic effects of the synthesized compounds (2–29) were evaluated on Allium cepa, Bidens pilosa, Cucumis sativus, Sorghum bicolor, and Solanum lycopersicum. RESULTS: Reaction of endo‐bicyclo[2.2.1]hept‐5‐ene‐3a,7a‐dicarboxylic anhydride (1) with aromatic amines led to the N‐phenylnorbornenesuccinic acids (2–11) with yields ranging from 75% to 90%. Cyclization of compounds (2–11) in the presence of acetic anhydride and sodium acetate afforded N‐phenylnorbornenesuccinimides (12–20) with yields varying from 65% to 89%. Those imides were then subjected to epoxidation reaction to afford N‐phenylepoxynorbornanesuccimides (21–29) with yields from 60% to 90%. All compounds inhibited the growth of seedlings of the plants evaluated. Substance 23 was the most active against the plants tested, inhibiting 100% the growth of all species in all concentrations. Cyclophilin was found to be the enzymatic target of compound 23. CONCLUSION: These findings suggest that derivatives of N‐phenylnorbornenesuccinimide are promising compounds in the quest for more selective and stable agrochemicals. This perspective reinforces the significance of these derivatives as potential innovative herbicides and emphasizes the importance of further exploring their biological activity on weeds. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Thiocyanates form an important class of organic compounds commonly found in natural products that exhibit excellent antimicrobial activity. The electrophilic thiocyanation is one of the most effective methods of introducing a -SCN functional group to the parent organic molecule. In this work, we explored an eco-friendly and highly efficient method for thiocyanation of anilines and 1-(substituted benzylidene)-2-phenylhydrazines using commercially available N-bromoscuccinimide (NBS) and potassium thiocyanate (KSCN). The optimized protocol afforded thiocyanates with good regioselectivity and excellent yields in comparison to the available methods.

Polysubstituted acrylamides are ubiquitous in bioactive molecules and natural products. However, synthetic methods for the assembly of these important motifs remain underdeveloped. Herein, we report the expedient synthesis of structurally diverse and synthetically challenging polysubstituted acrylamides from readily available aromatic amines, cyclopropenones (CpOs), and aryl halides via the synergistic merging of nucleophilic phosphine-mediated amidation and palladium-catalyzed C–H arylation. The reaction is scalable, and some obtained acrylamides proved to be solid state luminogens with obvious aggregation-induced emission (AIE) properties, demonstrating the synthetic potential in drug discovery and material development. [ABSTRACT FROM AUTHOR]

The covalent organic frameworks/polymers configurated with metal‐N4 conjugated structures offer an exceptional platform for efficient electrochemical CO2 reduction reaction (eCO2RR). However, understanding the impact of the structure‐mediated local microenvironment and integrating CO2 electroreduction with follow‐up utilization toward extending chemical valorization of CO2 are still far from sufficient. Herein, a set of covalent phenanthroline‐porphyrin polymers are designed to decode the microenvironment modulation originating from built‐in structures, and the optimized one delivered an extraordinary performance for eCO2RR with ≈100% Faradaic efficiency of CO under stabilized CO2‐electrolysis of 70 h. The experimental and theoretical analyses suggest that the regulation of the Co‐N4 electronic structures and microenvironment convoys the stabilized formation of key reaction intermediate *COOH. Furthermore, through CO‐mediated electro/thermocatalytic tandem processes, the aminocarbonylation of aryl iodides and amines with high yields has been convincingly implemented over the coordinated Pd sites, which is remarkably helpful to propel extending chemical valorization of CO2. [ABSTRACT FROM AUTHOR]

Despite the importance of difluoromethylene fragments in medicine, agrochemistry, and materials science, the precise and sustainable C–H difluoromethylation of aryl rings remains a challenge. Studies of metal-free difluoromethylation at room temperature would be advanced if methods were as reliable and modular as metal catalysis. Herein, we present a green and environmentally friendly modular platform for the sustainable para-difluoromethylation of readily available aromatic amines via a metal-free photocatalytic system. The reaction, for the first time, exhibits excellent functional group tolerance and broad substrate scope with a radical–radical coupling C–H functionalization strategy, rapidly delivering a variety of valuable difluoromethylated products. Furthermore, the derivatization of various complex molecules with high atom economy further demonstrates the synthetic utility and practicality of this protocol. A series of experimental studies and DFT calculations corroborate the plausible reaction mechanism. [ABSTRACT FROM AUTHOR]

This article explores the challenges and strategies involved in selectively adding carbon-based units to nonactivated alkenes. The authors focus on the use of directing groups, specifically a quinolinamide directing group, in a nickel-catalyzed reaction. This method allows for the efficient synthesis of branched molecules and demonstrates a high level of selectivity. The authors provide experimental results and optimization of reaction conditions to support their findings. Additionally, the article discusses the broad functional-group tolerance of the reaction and its potential applications in pharmaceutical modifications and large-scale reactions. [Extracted from the article]

The covalent organic frameworks/polymers configurated with metal‐N4 conjugated structures offer an exceptional platform for efficient electrochemical CO2 reduction reaction (eCO2RR). However, understanding the impact of the structure‐mediated local microenvironment and integrating CO2 electroreduction with follow‐up utilization toward extending chemical valorization of CO2 are still far from sufficient. Herein, a set of covalent phenanthroline‐porphyrin polymers are designed to decode the microenvironment modulation originating from built‐in structures, and the optimized one delivered an extraordinary performance for eCO2RR with ≈100% Faradaic efficiency of CO under stabilized CO2‐electrolysis of 70 h. The experimental and theoretical analyses suggest that the regulation of the Co‐N4 electronic structures and microenvironment convoys the stabilized formation of key reaction intermediate *COOH. Furthermore, through CO‐mediated electro/thermocatalytic tandem processes, the aminocarbonylation of aryl iodides and amines with high yields has been convincingly implemented over the coordinated Pd sites, which is remarkably helpful to propel extending chemical valorization of CO2. [ABSTRACT FROM AUTHOR]

Reductive N‐11C‐methylation using [11C]formaldehyde and amines has been used to prepare N‐11C‐methylated compounds. However, the yields of the N‐11C‐methylated compounds are often insufficient. In this study, we developed an efficient method for base‐free reductive N‐11C‐methylation that is applicable to a wide variety of substrates, including arylamines bearing electron‐withdrawing and electron‐donating substituents. A 2‐picoline borane complex, which is a stable and mild reductant, was used. Dimethyl sulfoxide was used as the primary reaction solvent, and glacial acetic acid or aqueous acetic acid was used as a cosolvent. While reductive N‐11C‐methylation efficiently proceeded under anhydrous conditions in most cases, the addition of water to the reductive N‐11C‐methylation generally increased the yield of the N‐11C‐methylated compounds. Substrates with hydroxy, carboxyl, nitrile, nitro, ester, amide, and phenone moieties and amine salts were applicable to the reaction. This proposed method for reductive N‐11C‐methylation should be applicable to a wide variety of substrates, including thermo‐labile and base‐sensitive compounds because the reaction was performed under relatively mild conditions (70°C) without the need for a base. [ABSTRACT FROM AUTHOR]

The development of the textile industry has negative effects on the natural environment. Cotton cultivation, dyeing fabrics, washing, and finishing require a lot of water and energy and use many chemicals. One of the most dangerous pollutants generated by the textile industry is dyes. Most of them are characterized by a complex chemical structure and an unfavorable impact on the environment. Especially azo dyes, whose decomposition by bacteria may lead to the formation of carcinogenic aromatic amines and raise a lot of concern. Using the metabolic potential of microorganisms that biodegrade dyes seems to be a promising solution for their elimination from contaminated environments. The development of omics sciences such as genomics, transcriptomics, proteomics, and metabolomics has allowed for a comprehensive approach to the processes occurring in cells. Especially multi-omics, which combines data from different biomolecular levels, providing an integrative understanding of the whole biodegradation process. Thanks to this, it is possible to elucidate the molecular basis of the mechanisms of dye biodegradation and to develop effective methods of bioremediation of dye-contaminated environments. [ABSTRACT FROM AUTHOR]

Oxygen vacancies are one of the prominent types of defects in metal oxides. In addition to their role in modifying the electronic properties in solids, these sites have been shown to activate chemical bonds. As a result, the use of defect‐rich metal oxides in the organic transformations is promising. The article gives an overview of various chemical processes that are in use for the chemical reduction of aromatic nitro compounds to amines. Recently, application of oxygen vacancies in transition metal oxide for the selective reduction of aromatic nitro compounds to the corresponding amines has emerged as a new method of synthesis of amines. Oxygen vacancies in reducible oxide such as CuO have been shown to decompose hydrazine hydrate to H2 and in situ cause the reduction of nitro arenes to corresponding amines. This concept article discusses the literature pertaining to the synthesis of nitro reduction reaction, various strategies employed thus far and the place the defect‐mediated synthesis holds. The article also discusses the perspectives and challenges that remain to be addressed to gain more insights into the mechanistic understanding of the role of oxygen vacancies in nitro reduction and beyond. [ABSTRACT FROM AUTHOR]

Assembling graphene sheets into macroscopic fibers with graphitic layers uniaxially aligned along the fiber axis is of both fundamental and technological importance. However, the optimal performance of graphene-based fibers has been far lower than what is expected based on the properties of individual graphene. Here we show that both mechanical properties and electrical conductivity of graphene-based fibers can be significantly improved if bridges are created between graphene edges through covalent conjugating aromatic amide bonds. The improved electrical conductivity is likely due to extended electron conjugation over the aromatic amide bridged graphene sheets. The larger sheets also result in improved π-π stacking, which, along with the robust aromatic amide linkage, provides high mechanical strength. In our experiments, graphene edges were bridged using the established wet-spinning technique in the presence of an aromatic amine linker, which selectively reacts to carboxyl groups at the graphene edge sites. This technique is already industrial and can be easily upscaled. Our methodology thus paves the way to the fabrication of high-performance macroscopic graphene fibers under optimal techno-economic and ecological conditions. The performance of macroscopic graphene fibers is hampered by lower bonding strength between individual graphene sheets. Authors mitigate this by creating covalent conjugating linkages at sheet edges, improving mechanical and electrical properties. [ABSTRACT FROM AUTHOR]

This article discusses the use of aromatic amine catalysts in a specific chemical reaction. The researchers conducted experiments using different catalysts and found that aryl amines were more effective than alkyl amines. They also discovered that a commercially available proton sponge showed promise as a catalyst. The article explores the catalytic activity of a specific catalyst called cat14 and compares it to other catalysts. While cat14 showed promising results, the study concludes that another scaffold called phenotellurazine performed better in the reactions. Further research is being done to improve the phenotellurazine scaffold and other catalysts. [Extracted from the article]

A series of novel oxo-5-(trifluoromethyl)quinazolinyl amide derivatives were prepared starting from 2-aminobenzoic acid, reacted with 4-chlorobenzoyl chloride and obtained 2-(4-chlorophenyl)-5-(trifluoromethyl)-4H-benzo[d][1,3]oxazin-4-one, further on reaction with hydroxyl amine and obtained 2-(4-chlorophenyl)-3-(4-hydroxyphenyl)-5-(trifluoromethyl)-quinazolin-4(3H)-one, this compound on further react with ethyl bromoacetate to get ethyl 2-{4-[2-(4-chlorophenyl)-4-oxo-5-(trifluoromethyl)quinazolin-3(4H)-yl]phenoxy}acetate, further treated with aliphatic and aryl amine to obtain amide functionalized quinazoline derivatives. All the final compounds evaluated for anticancer activity against four human cancer cell lines such as HeLa – cervical cancer (CCL-2), COLO 205 – colon cancer (CCL-222), HepG2 – liver cancer (HB-8065), MCF7 – breast cancer (HTB-22) and promising compounds have been identified, and evaluated for docking interactions. [ABSTRACT FROM AUTHOR]

The synthesis of novel thiazolidinones 6-8A, diazetidenes 9-11A, and ethers 13- 18A was described using 2-aminobenzathiazole and 4-bromophenacyl bromide as starting materials. The reaction of 2-aminobenzathiazole with 4-bromophenacyl bromide afforded the product A1 in 80% yield. Position 5 at the product A1 5-(4- bromophenyl)imidazo(2,1-b)benzothiazole used to form carbaldehyede group A2 under Vilsmeier-Huck conditions. Schiff bases 3-5A were then produced via condensation of A1 various aromatic amines. The products 3-5A were reacted with naphthyl isocyanate and thioacetic acid to give the compounds 6-8A (77-90% yields) and 9-11A (92-97% yields), respectively. The product 2A was reduced with NaBH4 to provide the corresponding alcohol 12A in an excellent yield (97%). This was followed by the reaction with aryl halides via the Williamson reaction to afford the desired ethers 13-18A in yields ranging from 50 to 96%. All of the prepared compounds were characterized by FT-IR spectroscopy, and some of them were characterized by ¹H NMR and 13C NMR spectroscopy. A few products were evaluated for their antifungal, antibacterial, and antioxidant activities. [ABSTRACT FROM AUTHOR]

Thiocyanates form an important class of organic compounds commonly found in natural products that exhibit excellent antimicrobial activity. The electrophilic thiocyanation is one of the most effective methods of introducing a -SCN functional group to the parent organic molecule. In this work, we explored an eco-friendly and highly efficient method for thiocyanation of anilines and 1-(substituted benzylidene)-2-phenylhydrazines using commercially available N-bromoscuccinimide (NBS) and potassium thiocyanate (KSCN). The optimized protocol afforded thiocyanates with good regioselectivity and excellent yields in comparison to the available methods. [ABSTRACT FROM AUTHOR]

The abilities of Chinese quince free proanthocyanidins (FP) and bound proanthocyanidins (BP) at different levels (0.1%, 0.15%, and 0.3%) to mitigate heterocyclic aromatic amine (HAA) formation in fried chicken patties were investigated for the first time and compared with vitamin C (Vc). FP and BP reduced HAAs in a dose‐dependent manner. Significantly, high concentrations of FP (0.3%) resulted in a reduction of PhIP, harman, and norharman levels by 59.84%, 22.91%, and 38.21%, respectively, in chicken patties. The addition of proanthocyanidins significantly (p < 0.05) reduced the weight loss of fried chicken patties. Furthermore, a positive correlation was observed among pH, weight loss, and total HAA formation in all three groups (FP, BP, and Vc). Multivariate analysis showed that FP had a more pronounced effect than BP from the perspective of enhancing the quality of fried chicken patties and reducing the formation of HAAs. These results indicate that proanthocyanidins, both BP and FP, but especially FP, from Chinese quince can inhibit the formation of carcinogenic HAAs when added to protein‐rich foods that are subsequently fried. [ABSTRACT FROM AUTHOR]

[Display omitted] • The WO 3 decorated with Cu was developed to efficiently regulate O 2 active species. • Under irradiation of wavelength < 475 nm, O 2 tends to produce 1O 2 and •O. • Under irradiation with a long wavelength source (>475 nm), 1O 2 is mainly ROS. • Cu@CuO x /WO 3 with photo-regulated ROS generation exhibits excellent performance. Photocatalysts can absorb light and activate molecular O 2 under mild conditions, but the generation of unsuitable reactive oxygen species often limits their use in synthesizing fine chemicals. To address this issue, we disperse 1 wt% copper on tungsten trioxide (WO 3) support to create an efficient catalyst for selective oxidative coupling of aromatic amines to imines under sunlight irradiation at room temperature. Copper consists of a metallic copper core and an oxide shell. Experimental and density functional theory calculations have confirmed that Cu 2 O is the primary activation site. Under λ < 475 nm, the light excites electrons of the valence bands in Cu 2 O and WO 3 , which activate O 2 to superoxide radical •O 2 −. Then rapidly transforms into oxygen adatoms (•O) and oxygen anion radicals (•O−) species on the surface of Cu 2 O. Simultaneously, it is captured by holes in the WO 3 valence band to generate singlet oxygen (1O 2). •O bind to 1O 2 promoting the coupling reaction of amines. When λ > 475 nm, intense light absorption due to the localized surface plasmon resonance excites numerous electrons in Cu to promote the oxidative coupling with the adsorbed O 2. This study presents a promising approach towards the design of high-performance photocatalysts for solar energy conversion and environmentally-friendly oxidative organic synthesis. [ABSTRACT FROM AUTHOR]

The purpose of the present research was to study the impact of bitter melon extract (BME) on the generation of heterocyclic aromatic amines (HAAs) in chicken thigh meat. Raw chicken samples were marinated overnight with various levels (0%, 0.5%, and 1%) of BME, and pan‐fried at 150, 200, and 250°C for a total of 10 min. IQx, IQ, MeIQx, MeIQ, 7,8‐DiMeIQx, 4,8‐DiMeIQx, PhIP, AαC, and MeAαC were detected in quantities that varied according to the cooking temperature and the concentration of BME. Notably, IQx, MeIQx, MeIQ, 7,8‐DiMeIQx, 4,8‐DiMeIQx, and AαC levels were reduced through the application of the marinade. Cooking at higher temperatures led to elevated levels of total HAAs. Total HAA levels were 0.98 ± 1.12 ng/g, 3.82 ± 2.12 ng/g, and 6.25 ± 3.35 ng/g in samples cooked at 150, 200, and 250°C, respectively (p <.01). BME demonstrated its effectiveness in mitigating total HAA levels, showing reductions ranging from 25.9% to 69.9%. The most effective concentration of BME in reducing total HAAs was 1% for all cooking temperatures, which might be attributed to its antioxidant activity. These results carry substantial implications for potentially incorporating natural extracts such as BME into chicken products as a viable strategy to reduce HAAs, thus enhancing the safety and quality of meat products. [ABSTRACT FROM AUTHOR]

We report a one-step synthesis of trifluoromethyl-substituted di(pyridin-2-yl)amine-based ligands. N-(hetero)aryl-substituted bis(5-(trifluoromethyl)pyridin-2-yl)amines were obtained from 2-bromo-5-(trifluoromethyl)pyridine and corresponding aromatic amines via Pd-catalyzed amination reaction in the presence of a Pd(dba)2/BINAP catalytic system. Four new ligands were prepared in good to high yields and characterized by NMR, IR spectroscopies and mass spectrometry. The structure of one of the products was additionally supported by X-ray analysis. [ABSTRACT FROM AUTHOR]

Four cellulose derivatives bearing benzothienyl or carbazolyl fluorophore pendants were successfully synthesized through carbamoylation followed by Steglich esterification or only esterification process, respectively. The enantioselective fluorescent sensing properties of the obtained derivatives were then evaluated using eight chiral substrates, including chiral aromatic amines and chiral amino alcohol-based drug intermediates. The four bulky host macromolecules exhibited good enantioselective fluorescence response to most of the tested guests with high enantioselectivity and sensitivity. Especially, a high enantiomeric fluorescence difference ratio (ef = 37.16) was achieved on cellulose tris(2-benzothienylformate) (Cel-3) for the α-methylbenzylamine (Q2), an important chiral agricultural drug intermediate. Worthy to be mentioned, an interesting opposite fluorescence response and a dual fluorescence enhancement pattern were also observed on the benzothienyl derivative Cel-3 for the enantiomer pairs of 1-(4-methoxyphenyl) ethylamine (Q3) and phenylglycinol (Q6), a critical intermediate for chiral drug as an antilipemic agent in high demand, respectively. It indicated that the bulky Cel-3 possessed excellent enantioselective fluorescent sensing properties to the chiral aromatic amine and amino alcohols, revealing good potential as efficient chiral fluorescent sensors. It was speculated that a beneficial chiral domain may be constructed by the appropriate arrangement of bulky conjugated benzothienyl or carbazolyl pendants on the phenylcarbamates or esters surrounding the helical backbone of cellulose, which was crucial for the efficient chiral fluorescent sensing performance. The introduction of bulky fluorophore pendants on the cellulose phenylcarbamates or esters presents an efficient strategy to produce effective chiral fluorescent recognition materials. [ABSTRACT FROM AUTHOR]