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A tetrafunctional glycidyl ether cyclic siloxane epoxy resin (TGTS) has been synthesized, characterized and cured with four aromatic amine hardeners: 1,3‐phenylenediamine (PDA), diethyltoluenediamine (DETDA), 4,4‐diaminodiphenylmethane (DDM) and 1,3‐bis(4‐aminophenoxy)benzene (APB). Each of the cured networks produces transparent and homogeneous networks, although when TGTS is cured with DETDA, reduced compatibility led to lower epoxide consumption, a more heterogenous microstructure and deleterious effects upon properties. Reduced miscibility of DETDA significantly impacts the chemical structure and microstructure of the network, resulting in significant reductions in thermal and mechanical properties but higher UV‐A transmission. The PDA‐, APB‐ and DDM‐cured networks conversely were more miscible and display properties typical of organic–inorganic hybrid networks, such as good mechanical properties at ambient and sub‐ambient temperatures, comparatively high glass transition temperatures, improved resistance to oxidation and lower UV‐A transmission. © 2024 The Author(s). Polymer International published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Reported herein is the first viable copper-free bimetallic catalyst for one pot multicomponent synthesis of 1,4-disubstituted 1,2,3-triazoles. A simple thermal procedure followed by two separate solution-phase synthesis methods have been designed to develop a series of Ag-based NPs (namely Ag and Ag2O) supported on the nanorod architecture of ZnO. Utilizing the as-synthesized NPs as the catalyst, we present the first one-step synthesis of 1,4-disubstituted 1,2,3-triazoles at room temperature, in which both benzyl bromides and aryl amines afford their respective benzyl azides and phenyl azides in situ under mild reaction conditions. The catalytic role of the as-synthesized nanoheterostructures was compared with their individual counterparts, revealing that the distinct structural features and oxidation state of Ag in Ag–ZnO and Ag2O–ZnO NPs play a crucial role in the unprecedented catalytic behaviour. Among all, Ag2O–ZnO emerges as the dominant catalyst for the regioselective AAC reaction. Our catalytic protocol eliminates the usage of any external additives, harsh reaction conditions and time-consuming catalyst synthesis. High recoverability of the catalyst (for at least eight catalytic cycles) made the process more useful. The 100% regioselectivity is strongly validated by a single crystal X-ray structure of one of the desired products. It also covers a broad substrate range with extensibility to some medicinally important drug molecules. Because of its gram-level scalability, the protocol can also be designed for industrial use. [ABSTRACT FROM AUTHOR]

Two different one‐pot synthetic protocols have been developed for obtaining 2,3‐disubstituted quinazolin‐4(3H)‐ones using pyridinium p‐toluenesulfonate (PPTS) as catalyst. The two‐component reaction involves isatoic anhydride and N‐acetyl amine whereas the three‐component reaction use isatoic anhydride, aryl amine and β‐diketone in Toluene under classical heating at 80–100 °C to afford 2,3‐disubstituted quinazolin‐4(3H)‐ones in good yields. The two‐component reactions are compatible with various substituted aryl/alkyl amines. [ABSTRACT FROM AUTHOR]

Electrosynthesis represents a dynamic field in organic chemistry for the development of important and selective reactions. Among the most interesting electrosynthetic transformations is the non‐directed arene C−H amination. Despite increasing reports, the quest for a non‐directed electrochemical arene C−H amination capable of accommodating a wide range of arenes and amines with high site‐selectivity remains ongoing. Non‐directed electrochemical C−H amination presents a metal‐free, mild approach for synthesizing complex aminated compounds of interest in pharmaceuticals and natural products. This concept aims to introduce the concept of non‐directed electrochemical C−H amination and provide an overview of the recent advances in the field as well as the current limitations and potential directions. [ABSTRACT FROM AUTHOR]

The synthesis and isolation of [Ru(Cp)(PCy2NPh2)(=C=CHPh]PF6 and [Ru(Cp*)(PCy2NCy2)(=C=CHPh)]PF6 was successfully accomplished. Use of these ruthenium vinylidene complexes for stoichiometric reactions with a variety of amines was performed. Upon reaction with alkyl amines, deprotonation of the Cβ hydrogen resulted in formation of acetylide complex [Ru(Cp*)(PCy2NPh2)(−C≡CPh)], and the species was confirmed through independent synthesis. In contrast, reaction of the less basic aryl amine aniline with [Ru(Cp)(PCy2NCy2)(=C=CHPh)]PF6 resulted in outer sphere addition to give a Fischer carbene product. [ABSTRACT FROM AUTHOR]

Density functional theory calculations have been conducted to investigate the palladium‐catalyzed allylic C−H amination of 1,4‐dienes with commonly available amines. The computations indicate that the reaction begins with the allylic C−H bond cleavage through the concerted proton and two‐electron transfer process to forge the η3‐allyl Pd(II) species. The ensuing C−N bond formation was found to be highly dependent on the basicity of the nucleophile, enabling the regioselectivity switch upon change of the nucleophile. With the weakly basic aromatic amine, the reaction occurs through the hydrogen‐bonding enabled inner‐sphere nucleophilic attack pathway. The distance between the reacting carbon atom and the terminal carbon atom is responsible for the Z/E‐selectivity. The regioselectivity is primarily due to steric repulsion between the allyl group and the ligand. On the other hand, the outer‐sphere nucleophilic attack pathway is favored for the reaction with the more basic aliphatic cyclic amine. The change of the coordinating mode of the allylic moiety was found to play a crucial role in determining the regioselectivity. [ABSTRACT FROM AUTHOR]

The significant synthetic potential and reactivity of tetracyanoethylene (TCNE) have captured the interest of numerous chemical communities. One of the most promising, readily achievable, yet least explored pathways for the reactivity of TCNE involves its interaction with arylamines. Typically, the reaction proceeds via tricyanovinylation (TCV); however, deviations from the standard chemical process have been observed in some instances. These include the formation of heterocyclic structures through tricyanovinyl intermediates, aliphatic dicarbonitriles through the cleavage of the C–C bond of a tetracyanoethyl substituent, complexation, and various pericyclic reactions. Therefore, the objective of this study is to review the diverse modes of interaction of TCNE with aromatic nitrogen-containing compounds and to focus the attention of the chemical community on the synthetic capabilities of this reagent, as well as the various biological and optical activities of the structures synthesized based on TCNE. [ABSTRACT FROM AUTHOR]

A novel CVO/TiO2 heterojunction material has been prepared and used to catalyze the oxidative aromatization of amines and cyclohexenones under visible light irradiation, avoiding the use of noble metal catalysts and providing an environmentally friendly alternative for the synthesis of aromatic amines. The catalytic reaction uses oxygen as the final oxidant and provides good yields over a wide range of substrates. Notably, the recyclable heterogeneous semiconductor photocatalyst can be readily recovered and reused for at least four cycles. In addition, several biologically active molecules were successfully synthesized using the photocatalytic method. [ABSTRACT FROM AUTHOR]

Thermal treatment of food can lead to the formation of potentially harmful chemicals, known as process contaminants. These are adventitious contaminants that are formed in food during processing and preparation. Various food processing techniques, such as heating, drying, grilling, and fermentation, can generate hazardous chemicals such as acrylamide (AA), advanced glycation end products (AGEs), heterocyclic aromatic amines (HAAs), furan, polycyclic aromatic hydrocarbons (PAHs), N-nitroso compounds (NOCs), monochloropropane diols (MCPD) and their esters (MCPDE) which can be detrimental to human health. Despite efforts to prevent the formation of these compounds during processing, eliminating them is often challenging due to their unknown formation mechanisms. It is critical to identify the potential harm to human health in processed food and understand the mechanisms by which harmful compounds form during processing, as prolonged exposure to these toxic compounds can lead to health problems. Various mitigation strategies, such as the use of diverse pre- and post-processing treatments, product reformulation, additives, variable process conditions, and novel integrated processing techniques, have been proposed to control these food hazards. In this review, we summarize the formation and occurrence, the potential for harm to human health produced by process contaminants in food, and potential mitigation strategies to minimize their impact. [ABSTRACT FROM AUTHOR]

This review summarises and discusses aryl amine and azide syntheses from aryl halides employing azides. The majority of the reported reactions proceed with copper catalysis or mediation. Often, an aryl azide is formed in the first step, which is then reduced in situ to an aryl amine in a second step. The occurrence of the second step, the reduction, depends on the chosen reaction conditions and the substrates. The formation of only aryl azides through Cu‐mediated C−N bond formations is discussed, followed by mediated and catalytic aryl azide reduction employing different catalytic systems, and azidation with in situ azide reduction to amines, viz. azidation‐amination strategies. The azidation‐amination allows for the synthesis of complex heterocycles in multi‐step one‐pot procedures, of which several are summarised here. Examples of the application of azidation‐amination for synthesising important aryl amines employed in or as biologically active compounds, catalysis and materials science are also summarised. Finally, conducted control reactions have been collected and discussed in combination with mechanistic proposals. This literature survey allows us to pinpoint design criteria for the azide reduction to valuable amines, which includes the choice of reaction conditions such as solvent system and additives, involved metal and promising substrates. [ABSTRACT FROM AUTHOR]

We report the synthesis of alkyl 1,2,6‐triaryl‐4‐arylaminopiperidine‐3‐ene‐3‐carboxylates in acceptable yields (42%–71%) and high trans‐diastereoselectivity (69:31 to 100:0) through a one‐pot multicomponent reaction of aromatic aldehydes, aromatic amines, and β‐ketoesters catalyzed by phosphomolybdic acid in methanol at room temperature. The structure and stereochemistry of tetrahydropyridines were confirmed by X‐ray crystallography. This protocol stands out for its operational simplicity, the use of an inexpensive and commercially available heteropolyacid catalyst, low catalyst loading, and purification via simple filtration, resulting in acceptable yields and high diastereoselectivity. [ABSTRACT FROM AUTHOR]

An efficient one‐step reagent‐free synthesis of 4‐Aryl/alkylamino‐1,2‐naphthoquinones in water and iPrOH (1 : 1) mixture was carried out at room temperature (RT) using 4‐amino‐3‐hydroxynaphthalene‐1‐sulfonic acid and various primary and secondary aryl and alkyl amines. The reaction did not proceed in the absence of air or oxygen. In all cases, good yields (isolated yield: ≥65 %) were observed. The compounds exhibited fluorescence emission bands (400–470 nm) in the visible region upon excitation at their respective λmax values (330–350 nm). We evaluated in vitro cytotoxicity of some of the derivatives against two human breast cancer cell lines (MCF‐7, and MDA‐MB‐231) using the WST‐1 assay. The naphthoquinone derivatives did not show any cytotoxic effects at concentration levels relevant to cellular fluorescence imaging. The imaging experiments revealed that a few of the derivatives hold the potential to be used as cellular fluorescent imaging probes. [ABSTRACT FROM AUTHOR]

Phenylhydroxylamine and its derivates (PHAs) are important chemical intermediates. Phenylhydroxylamines are mainly produced via the catalytic reduction of aromatic nitro compounds. However, this catalytic reduction method prefers to generate thermodynamically stable aromatic amine. Thus, designing suitable catalytic systems, especially catalysts to selectively convert aromatic nitro compounds to PHAs, has received increasing attention but remains challenging. In this review, we initially provide a brief overview of the various strategies employed for the synthesis of PHAs, focusing on reducing aromatic nitro compounds. Subsequently, an in-depth analysis is presented on the catalytic reduction process, encompassing discussions on catalysts, reductants, hydrogen sources, and a comprehensive assessment of the merits and drawbacks of various catalytic systems. Furthermore, a concise overview is provided regarding the progress made in comprehending the mechanisms involved in this process of catalytic reduction of aromatic nitro compounds. Finally, the main challenges and prospects in PHAs' production via catalytic reduction are outlined. [ABSTRACT FROM AUTHOR]

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 response to the challenge of antibiotic-resistant microorganisms, oxazolone analogs are frequently used for bacterial, antiviral, and anti-inflammatory treatments. However, few studies have shown bis-oxazolone analogs possess antibacterial activities. In this study, we modified bis-oxazolone molecules with various aromatic amines to create new bis-benzamide and bis-imidazolone derivatives. These derivatives were analyzed using FTIR, 1H-NMR, and 1,3C-NMR spectroscopy. Molecular docking revealed favorable interactions with DNA gyrase, with compounds 3, 4a, and 5e showing higher binding affinities than penicillin G and ampicillin. These findings suggest their potential as future antimicrobial agents. The tested compounds demonstrated efficacy against bacterial strains, particularly E. coli and S. aureus, with significant activity observed in compounds 4a, 4e, 5d, and 5e. Antioxidant activity, assessed using the DPPH method, showed bis-compounds with excellent results comparable to ascorbic acid. This encourages further studies to explore their potential. Overall, the synthesized bis-oxazolone derivatives demonstrated increased medicinal activity and high potential as future antimicrobial and antioxidant agents. [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]

We report the reticular synthesis and structural investigations through the spectroscopic analysis of a novel polyhedral oligomeric silsesquioxane (POSS)-modified framework, hereby ascribed as a catalyst for the selective reduction of aryl nitriles to amines. The integration of the unique features of the polyhedral oligomeric silsesquioxane with 2,2′-Bipyridine-4,4′-dicarboxaldehyde and subsequently coordination to cobalt acetate manifests a distinctive feature, which is a stable covalent bond between Co and the functionalized POSS, effectively preventing catalyst leaching. The cobalt acetate-modified POSS–COF, synthesized with this approach, underwent a comprehensive characterization employing various analytical techniques including FTIR, XRD, SEM, XPS, TGA, and 29Si NMR. This thorough characterization provides a detailed insight into the structural and chemical attributes of the catalyst. Our catalyst, with its exceptional catalytic efficiency in catalyzing reduction reactions compared to its homogeneous counterparts, and its distinctive three-dimensional metalated POSS system, shows outstanding catalytic performance attributed to its diverse coordination interactions with ligands. Moreover, this catalyst presents additional merits, such as facile recovery and recyclability, making it a promising candidate for sustainable and efficient catalytic processes and thus instilling hope for a greener future. [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]

In the present work, inexpensive and commercially available diethyltriamine pentaacetic acid (DTPA) was used as an initiator to catalyze the N-formylation reaction of CO2 with amines via the construction of C-N bonds in the presence of xanthone as the photosensitizer and PhSiH3 as the reducing agent. After a systematic study of various factors, the optimal conditions for the photocatalytic reaction were obtained: 2.5 mmol of amine, 2.5 mmol of PhSiH3, 10 mol% of DTPA, 20 mol% of xanthone, 1 mL of dimethylsulfoxide (DMSO), atmospheric pressure, and 35 W UV lamp irradiation for 48 h. Under the optimal conditions, the catalyst system afforded high performance for the N-formylation of amines (primary and secondary amines) and CO2, and the yields of the N-formylated products of dialkylamines were above 70%. Further studies exhibit that the catalytic system has a wide scope of substrate applications. For various alicyclic secondary amines, heterocyclic secondary amines, aliphatic primary amines, and aromatic primary amines, the corresponding N-formylation products can be obtained efficiently. In addition, the catalyst can be recycled by simple precipitation and filtration. After five cycles of recycling, there was no significant change in the catalytic and structural properties of DTPA. Finally, a possible reaction mechanism is proposed. [ABSTRACT FROM AUTHOR]

With rising consumer awareness of health and wellness, the demand for enhanced food safety is rapidly increasing. The generation of chemical contaminants during the thermal processing of food materials, including polycyclic aromatic hydrocarbons, heterocyclic aromatic amines, and acrylamide happens every day in every kitchen all around the world. Unlike extraneous chemical contaminants (e.g., pesticides, herbicides, and chemical fertilizers), these endogenic chemical contaminants occur during the cooking process and cannot be removed before consumption. Therefore, much effort has been invested in searching for ways to reduce such thermally induced chemical contaminants. Recently, the addition of bioactive compounds has been found to be effective and promising. However, no systematic review of this practical science has been made yet. This review aims to summarize the latest applications of bioactive compounds for the control of chemical contaminants during food thermal processing. The underlying generation mechanisms and the toxic effects of these chemical contaminants are discussed in depth to reveal how and why they are suppressed by the addition of certain bioactive ingredients. Examples of specific bioactive compounds, such as phenolic compounds and organic acids, as well as their application scenarios, are outlined. In the end, outlooks and expectations for future development are provided based on a comprehensive summary and reflection of references. [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]

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]

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]

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]

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]

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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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

In the context of ongoing research, an efficient single-step multicomponent reaction synthesis for new tetrazole scaffolds has been developed. The Ugi multicomponent process is one of the most promising approaches for the connection of four separate components in a single phase and finds immense application in drug discovery. In this study, tetrazoles were synthesized using the Ugi-Multi Component technique, which involved the condensation of isocyanides, TMS-N3, different aryl amines, aromatic aldehydes with active pharmacophores. Final products were characterized by various spectroscopic techniques viz. IR, NMR, and Mass spectrometry. Tetrazole derivatives were screened for their anticancer activity against the NCI-60 cell lines grouped in 9 different subpanels among which compounds 5b and 5e have been found to be more potent against different cell lines. In order to get mechanistic insights into this antitumor activity, molecular docking analysis against critical target CDK2 was performed. The results of binding affinity were in harmony with the anticancer activity and could provide valuable insights into the various thermodynamic interactions governing the binding affinity. [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]

In this research, the preparation of lipoamide through direct amidation of fatty acid and via amidation of fatty acid methyl ester (FAME) was compared. The reactivity of aromatic amines and cyclohexylamine for the synthesis of lipoamide was investigated in this research. The performance of saturated and unsaturated fatty acids was also compared. The synthesis of lipoamides via direct amidation was conducted under reflux using a Dean-Stark trap and silica gel as the catalyst. On the other hand, the amidation of FAME was carried out without catalysts and solvent. Both reactions were run simultaneously for 18 hours at the same temperature. The reaction was monitored using TLC, and then the product was purified using column chromatography and characterized using FTIR and ¹H NMR. The TLC data, FTIR, and ¹H NMR spectra confirmed that both reaction pathways produced the same lipoamide as the product. Both reaction pathways were compatible with aromatic and nonaromatic amines and saturated and unsaturated fatty acids. The reaction yield of lipoamide from direct amidation was around 70-80% and two-fold higher than lipoamide synthesis via amidation of FAME. Therefore, direct amidation of fatty acid was preferred for the synthesis of lipoamides compared to via amidation of FAME. [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]

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]