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Wastewater pollution is a pressing environmental issue, necessitating effective remediation strategies to mitigate its impact. This study investigates the use of an efficient catalyst for degrading nitrophenols by converting them into useful aromatic amines, which are crucial building blocks for many pharma industries, and photodegradation of various dyes in their unitary solution as well as in mixture. The Cu-Co-Mn ferrite was synthesized using the sol-gel process and sintered at different temperatures. Structural analysis using XRD and Rietveld refinement revealed a crystal structure corresponding to the Fd 3 ‾ m space group having high purity in all the samples. Additionally, the impact of sintering temperature on the magnetic features of the phases were also studied and the findings suggest that all the phases exhibit ferromagnetic behaviour, which means they can be easily separated from reaction mixtures using an external magnetic field. It was also found that higher sintering temperatures lead to a rise in saturation magnetization and magnetic moment with decrease in coercivity (H c). Further, it was observed that Curie temperature (T c) increases with increase in sintering temperature with the exception of CFM400. The catalytic performance of all the catalysts, including CFM400, CFM500, CFM600, CFM800, and CFM1000, was evaluated and the results indicate that CFM400 exhibits the highest catalytic activity for nitrophenols reduction and photodegradation of dyes, which could be accredited to its larger BET surface area and lower PL intensity. Overall, the structural and magnetic features of the catalyst's sheds light on the underlying mechanisms governing their catalytic activity. These insights offer valuable guidance in the designing and development of effective catalysts for sustainable wastewater treatment practices, emphasizing the importance of considering both structural and magnetic features in catalyst design. [ABSTRACT FROM AUTHOR]

Drawing on prior reports highlighting the redox mediator properties of powdered activated carbon (PAC), this study was designed to evaluate these properties to enhance the decolorization of azo dye by Klebsiella quasipneumoniae GT7. It was found that the presence of 0.5 % PAC in the medium increased the biodecolorization rate early in incubation. Chemical analysis revealed that dye conversion into aromatic amines occurred in microbial systems both with and without PAC. However, at initial dye concentrations (C id) of 2 mM or higher, some dye remained on the PAC surface and in the medium. In contrast, the PAC-free system achieved nearly 100 % biodecolorization at all initial dye concentrations. The negative impact of PAC on decolorization efficiency in microbial systems with high initial dye concentrations cannot be solely explained by its redox mediator function. This study used the amphoteric-Donnan model for PAC's electrical double layer (EDL) and Mitchell's chemiosmotic model for bacterial proton motive force (PMF) to explore this. It found that charge storage in PAC's EDL regulates electron transfer fluxes, and proton species enhance the proton motive force across the bacterial membrane. These observations improve the understanding of PAC's role in microbial decolorization and its potential future applications. [Display omitted] • Dye biodegradation occurs mainly on activated carbon's porous surface in the medium. • Activated carbon enhances biodecolorization at low initial dye concentrations. • At high initial dye levels, activated carbon reduces final biodecolorization yield. • Charge storage in carbon's electrical double layer controls electron transfer flux. • Proton storage on carbon boosts proton motive force across the bacterial membrane. [ABSTRACT FROM AUTHOR]

ABSTRACT A series of N,N‐chelate half‐sandwich ruthenium complexes based on N‐phenylpicolinamide ligands has been prepared with good yields through a facile route. These air and moisture stable N,N‐chelate half‐sandwich ruthenium complexes showed good catalytic efficiency in transamidation reactions between aromatic amines and amides under mild reaction conditions. A variety of secondary amides was obtained in high yields under open flask condition with broad substrates and good group tolerance. The excellent catalytic activity, broad substrate range, and mild reaction conditions make this catalytic system a potential candidate for industrial production. In addition, the structure of the prepared ruthenium complex has been confirmed by single crystal X‐ray diffraction. [ABSTRACT FROM AUTHOR]

AbstractThe aza-Michael addition reaction of primary and secondary amines to α,β-unsaturated olefins viz; acrylonitrile, phenyl vinyl sulfone and dimethyl maleate has been carried out using 5–10 mol% Co(NO3)2.6H2O as a catalyst in t-BuOMe at 80–100 °C, giving rise to the desired β-aminocarbonyl compounds or sulfones in moderate to good yields. A wide range of aromatic amines, even those bearing electron withdrawing groups could be added to activated olefins via this strategy. Addition of (hetero)aromatic amines were also feasible, while in case of 2-aminopyridine the reaction was found to be effective only when AgOTf was added along with the catalyst. The aliphatic amines; benzylamine, dibenzylamine, di-n-butylamine were also smoothly added to acrylonitrile and phenyl vinyl sulfone. The methodology describes cobalt(II) nitrate as an eco-friendly, cheap and shelf available catalyst suitable for performing the Michael-type hydroamination reactions. [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]

AbstractA metal–organic framework (MOF-199) nanocomposite was coated on magnetic graphene oxide (MGO) as a sorbent (MGO/MOF-199) and used for the isolation of aromatic amines by magnetic solid-phase extraction (MSPE). The analytes subsequently determined using gas chromatography with a flame ionization detector (GC-FID). The sorbent mass, desorption solvent, extraction time, desorption time, and pH were optimized. The calibration plots demonstrate linear ranges from 0.1 to 500 ng mL−1 with correlation coefficients from 0.9908 to 0.9939. The limits of detection (LOD) were between 0.03 and 0.1 ng mL−1. To evaluate the repeatability, relative standard deviations (RSD) were evaluated for 0.1, 10, and 100 ng mL−1 of the aromatic amines, yielding values from 3.2% to 4.5%. The developed method was employed to extract aromatic amines from tap water, seawater, and spring water. The relative recoveries were from 97.2% to 99.9%. [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]

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]

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]

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]

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]

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]

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]

The reactivity of dimethylamine borane (DMAB) towards amines and nitroarenes was investigated in the presence of the CO2 and Pd/PVP (PVP=polyvinylpyrrolidone) nanocatalyst. The formation of borane formate, Me2NH.BH2(OCHO), by the insertion of CO2 into the B−H bond was evidenced by NMR. The reaction of DMAB with CO2 also produced a second product, DMF, formed via self‐formylation. In the presence of aromatic or aliphatic amines corresponding N‐formamides were formed efficiently. Under the same conditions nitroarenes were hydrogenated to anilines or to azoxyarenes in the absence of CO2. In both reactions very high TOF values, up to 30 min−1, were obtained. Applying a higher excess of DMAB enabled the transformation of nitroarenes to N‐formamides. The Pd/PVP catalyst was used in 7 consecutive cycles of N‐methylaniline formylation with excellent selectivity and a total TON equal to 4700. [ABSTRACT FROM AUTHOR]

Due to their unique semiconducting properties, conjugated porous organic polymers (CPOPs) have garnered significant interest in various photocatalysis applications. In this study, we synthesize three thiazolo[5,4‐d]thiazole (TzTz)‐linked CPOPs with three polyaryl rigid cores of benzene (CPOP1), pyrene (CPOP2), and triazine (CPOP3). We investigated their efficacy in catalyzing visible light‐driven C−N bond formation reactions, including C−N cross‐couplings between aryl bromides and amines and amination reactions from aryl bromides and sodium azides. Among the three, only CPOP2, combined with NiCl2 or Ni(dtbbpy)Cl2, effectively facilitated these transformations. Notably, CPOP2 exhibited photocatalytic activities approximately six times higher than its small molecular counterpart C1 in both reactions. The CPOP catalyst was easily recovered through centrifugal separation and reused for five catalytic cycles with minimal loss of activity. Theoretical calculations revealed that the deliberate structural design of polyaryl moieties could effectively tune the energy gap, which is crucial for the photocatalytic activity in organic reactions. This study, therefore, demonstrates a novel application of TzTz‐linked CPOPs for heterogeneous photocatalytic organic transformations. [ABSTRACT FROM AUTHOR]

Herein, a microwave promoted tandem reaction of free primary arylamines with diazo compounds in water for clean synthesis of 2,2‐disubstituted 3‐oxindoles is present. Water plays important roles in the whole cascade process: O−H insertion to diazo, air oxidation, ortho C−H functionalization, cyclization and 1,2‐ester migration. In particular, water plays a mediation role in the site selective ortho‐C−H addition. [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]

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]

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]

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]

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]

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]

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]

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]