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Neonicotinoid insecticides are among the most used insecticides and their residues are frequently found in surface water due to their persistence and mobility. Neonicotinoid insecticides exhibit toxicity to a wide range of aquatic invertebrates at environmentally relevant levels, and therefore their contamination in surface water is of significant concern. In this study, we investigated the spatiotemporal distribution of six neonicotinoids in a large wetland system, the Prado Wetlands, in Southern California, and further evaluated the wetlands' efficiency at removing these insecticides. Total neonicotinoid concentrations in water ranged from 3.17 to 46.9 ng L-1 at different locations within the wetlands, with imidacloprid and dinotefuran among the most detected. Removal was calculated based on concentrations as well as mass flux. The concentration-based removal values for a shallow pond (vegetation-free), moderately vegetated cells, densely vegetated cells, and the entire wetland train were 16.9%, 34.2%, 90.2%, and 61.3%, respectively. Principal component analysis revealed that pH and temperature were the primary factors affecting neonicotinoids removal. Results from this study demonstrated the ubiquitous presence of neonicotinoids in surface water impacted by urban runoff and wastewater effluent and highlighted the efficiency of wetlands in removing these trace contaminants due to concerted effects of uptake by wetland plants, photolysis, and microbial degradation.

Chemoselective reduction of nitroarenes to corresponding arylamines is a significant reaction in the chemical industry. However, in the presence of other reducible groups, including halogenated nitrobenzene, nitrobiphenyl, and nitroquinoline in the same molecule of nitroaromatics, the control of chemoselectivity remains challenging. Here, a facile fabrication of a heterogeneous iron‐based catalyst is reported as a potential alternative to precious metal catalysts for the chemoselective reduction of nitroarenes. The pyrolysis of iron acetate/polyacrylonitrile (PAN) template under an inert atmosphere furnishes active Fe3O4 nanoparticles (NPs) encapsulated in nitrogen‐doped (N‐doped) carbon layers, which can provide more catalytic active sites (Fe3O4/PAN@800). Notably, non‐precious iron oxide NPs supported on N‐doped carbon support prevent aggregation, thereby enhancing the catalytic activity. The sustainable and reusable Fe3O4/PAN@800 catalyst, having only 0.8% metal content as demonstrated by x‐ray photoelectron spectroscopy, delivers excellent yields of corresponding amines from differently functionalized nitroarenes. Hydrogenation of a series of structurally functionalized nitroarenes produced excellent yields of anilines, which serve as building blocks and intermediates for fine and bulk chemicals. Hydrogenation of 2‐chloro‐3‐nitropyridine, 2‐nitro‐1,1′‐biphenyl, ortho‐nitroaniline, and 4‐aminophenyl acrylonitrile yielded respective anilines up to 99%. The active sites of Fe3O4 have magnetic performance, hence, the catalyst can be easily recovered using a magnet and reused for at least five cycles without significant loss of catalytic activity. Therefore, the easily prepared, cost‐effective, and reusable Fe3O4/PAN@800 catalyst presented in this study shows potential for applications in the selective reduction of aromatic nitro compounds. Consequently, this study potentially establishes a guideline for the facile preparation of abundant transition‐non‐noble metal‐based reusable supported catalysts for various applications in the chemical industry. [ABSTRACT FROM AUTHOR]

The present article provides an overview of our work related to cyclization reactions of nitro-substituted electrophilic building blocks with various nucleophiles. As electrophiles, we used nitro-substituted benzoylacetones, 3-ethoxy-2-nitro-2-en-1-ones, 2-nitrobenzoyl chlorides, 4-chloro-3-nitrocoumarin, 2-nitromalonic aldehyde, 3-nitrochromone and 1-(2-chloro-5-nitrophenyl)prop-2-yn-1-ones. As nucleophiles, 1,3-dicarbonyl compounds, 1,3-bis(silyloxy)-1,3-butadienes, (heterocyclic) enamines, hydroxylamine, hydrazines, amines and amino esters were employed. The products include a variety of nitro-substituted carbo- and heterocycles that are not readily available by other methods. The electron-withdrawing nitro group can be easily transformed into an electron-donating amino group which is not only pharmacologically relevant, but can also act as a nucleophile in inter- and intramolecular reactions with electrophiles, such as aldehydes, and can be converted into other functional groups. The nitro group has the capacity to activate compounds for regioselective palladium-catalyzed CH-arylation reactions. Inter- and intramolecular CH arylations of nitro-substituted heterocyclic building blocks, such as 4-nitropyrazoles, 4-nitroimidazoles, 2-nitroindole and nitro-substituted purine analogues, allow for a convenient diversity-oriented approach to the corresponding arylated products. In addition, the nitro group can act as a leaving group in SN Ar reactions. Various fused benzofuro[3,2- b ]pyridines were prepared by intramolecular SN Ar reactions of 2-(hydroxyphenyl)-3-nitropyridines. 1 Introduction 2 Cyclizations of 1,3-Bis(silyloxy)-1,3-butadienes 3 Cyclizations of Heterocyclic Enamines 4 Reactions of Simple Nitro-Substituted Heterocycles 5 Hydroamination Reactions of Alkynes 6 Miscellaneous 7 Conclusions [ABSTRACT FROM AUTHOR]

Textile dyeing releases over 80% of industrial effluents without proper treatment. Dye discharged into effluents typically needs degradation before release into aquatic environments. In this regard, the present paper reports the nanocomposite copper oxide/polyaniline (CuO/PANI) is successfully synthesized by in situ chemical oxidative polymerization method and investigates their catalytic activity against organic dyes and nitro compounds. CuO is synthesized by colloidal sol–gel method using oxalic acid as capping agent to obtained desired morphology. The elemental composition, unit cell and lattice parameters of nanocomposite are characterized by using XRD. The XRD revealed that nanoparticles are extremely crystalline, but nanocomposite is amorphous because of the presence of polymer. The structural and elemental analysis of CuO and CuO/PANI is confirmed by SEM and EDX analysis. FTIR spectra of CuO showed bending vibration, while CuO/PANI showed the presence of benzenoid and quinoid rings. Catalytic productivity of the CuO and CuO/PANI as catalysts in degradation of dyes and reduction of nitro compounds is also studied. The degradation and reduction processes are monitored through the utilization of UV–Vis spectrophotometer. The catalytic activity of both catalysts is evaluated by several parameters including kapp, degradation/reduction time, % degradation/reduction, degraded/reduced concentration and half-life. Among all substrates, highest kapp is 0.0653 min−1 for CV by CuO, while 0.0502 min−1 for EBT by CuO/PANI due to large surface area. On degradation and reduction rate of substrates, the impact of functional group type and orientation, bond type and steric hindrance is also investigated. [ABSTRACT FROM AUTHOR]

In this work, we designed and synthesized a series of novel triazolopyridine fused-ring compounds with alternating nitro and amine groups. Three compounds showed remarkable thermal stability at 256, 310, and 294 °C, respectively, and a low mechanical sensitivity [impact sensitivity (IS) = 40 J, friction sensitivity (FS) = 324 N; IS = 35 J, FS = 240 N; and IS > 40 J, FS = 324 N, respectively]. Significantly, two of these compounds exhibited a better detonation performance [detonation velocity (D) = 8200 and 8335 m s–1 , Detonation pressure (P) = 25.6 and 27.2 GPa, respectively] than the widely used heat-resistant explosive hexanitrostilbene (HNS; D = 7612 m s–1 , P = 24.3 GPa). Additionally, a nitramine derivative displayed a detonation performance (D = 8569 m s–1 , P = 31.3 GPa) similar to that of the high-energy explosive RDX. The superior properties of the materials were further confirmed by X-ray diffraction analysis and by several theoretical calculations (ESP, LOL–π, Hirshfeld surfaces, RDG, and NCI analyses). These results indicated that the three compounds might be potential candidates for use as heat-resistant energetic materials. [ABSTRACT FROM AUTHOR]

N‐heterocyclic compounds have a broad range of applications and their selective synthesis is very appealing for the pharmaceutical and agrochemical industries. Herein we report the usage of the flavin‐dependent nitroreductase BaNTR1 for the photoenzymatic synthesis of various anthranils and quinolines from retro‐synthetically designed o‐nitrophenyl‐substituted carbonyl substrates, achieving high conversions (up to >99 %) and good product yields (up to 96 %). Whereas the effective production of anthranils required the inclusion of H2O2 in the reaction mixtures to accumulate the needed hydroxylamine intermediates, the formation of quinolines required the use of anaerobic or reducing conditions to efficiently generate the essential amine intermediates. Critical to our success was the high chemoselectivity of BaNTR1, performing selective reduction of the nitro group without reduction of the carbonyl moiety or the activated carbon‐carbon double bond. The results highlight the usefulness of an innocuous chlorophyll‐ and nitroreductase‐based photoenzymatic system for the tailored synthesis of diverse N‐heterocycles from simple nitro compounds. [ABSTRACT FROM AUTHOR]

The detection of explosive materials, particularly nitroaromatic compounds such as 2,4,6‐trinitrotoluene (TNT), is critical for public safety and national security. Existing detection methods often require complex instrumentation, limiting their applicability for real‐time or in‐field use. Fluorescent sensors, which offer rapid and sensitive detection through fluorescence quenching, present a promising alternative. This study evaluates the performance of two pentiptycene‐based polymers, P‐1 and P‐2, in detecting explosive vapors, with a specific focus on their behavior under high‐humidity conditions. P‐2, modified with triethylene glycol groups, demonstrated significantly increased hydrophilicity compared to the commonly studied P‐1, as confirmed by contact angle measurements. Spectroscopic analysis revealed a blue shift in P‐2's UV–Vis absorption and photoluminescence spectra, indicating electronic property changes due to structural modifications. The enhanced hydrophilicity of P‐2 enabled it to maintain stable sensing performance under moist conditions, showing less than a 10% reduction in sensitivity, compared to the 20% decrease observed in P‐1. This superior moisture resistance suggests that P‐2 is a more robust and practical sensor for explosive detection in environments with variable humidity levels. [ABSTRACT FROM AUTHOR]

The compact, nitrogen‐rich structure of 2,4,6,8,10,12‐hexaazaisowurtzitanes calls attention among researchers worldwide. These compounds have found the greatest utility as substrates for nitration to obtain the caged polynitramine, 2,4,6,8,10,12‐hexanitro‐2,4,6,8,10,12‐hexaazaisowurtzitane, which possesses a high‐energy performance. All new derivatives of hexaazaisowurtzitane are nitratable. The present study examined the nitration process of 2,6,8,12‐tetraacetyl‐2,4,6,8,10,12‐hexaazaisowurtzitane derivatives obtained through the condensation reaction with aldehydes under various conditions to yield CL‐20. The yield of CL‐20, a well‐known nitration product of hexaazaisowurtzitane compounds, was found to depend on the substrate structure and the nitrating mixture composition. The revealed dependence of the synthesis of various nitrated compounds on the holding time enables the synthesis of products with different physicochemical properties in a single process. [ABSTRACT FROM AUTHOR]

A rapid practical new synthesis of multi-substituted pyrrole derivatives with high yields through a novel four-component reaction of sulfonyl azides, terminal alkynes, nitro compounds, and trichloroacetonitril is a remarkable achievement in organic chemistry. This strategy offers a direct and efficient route to access complex molecular structures from readily available starting materials. To expand the work, the reaction of the final product with sulfinate salt under simple conditions and room temperature, poly-substituted pyrroles with sulfone functional group are formed. The combination of available starting materials, catalytic systems, mild reaction conditions, and ease of purification procedures contributes to the attractiveness of this method for the synthesis of diverse multi-substituted pyrrole derivatives. [ABSTRACT FROM AUTHOR]

Two o-carborane-hybridized macrocyclic arenes have been synthesized via Friedel–Crafts alkylation of carborane diaryl derivatives. The single-crystal X-ray diffraction analysis clearly revealed their cavity structure and intermolecular interaction force. These novel macrocycles exhibited aggregation-induced luminescence and intramolecular charge transfer properties and also significant selectivity towards nitro explosive compounds. This work provided a method for the synthesis of hybridized macrocyclic arenes. [ABSTRACT FROM AUTHOR]

The nitrogen-and oxygen-rich azole-based high energetic compound 3,3′-(2-(trinitromethyl)-2H-1,2,3-triazole-4,5-diyl)-bis(1,2,4-oxadiazole) (5) was synthesized from a readily accessible bis-cyano-substituted-azole in three steps with an overall good yield. The reaction sequence was even successful on the gram scale. The five-membered azole backbone with a –C(NO2)3 group contributes to boosting energetic properties of the molecule. The synthesized compounds were fully characterized using NMR, IR, HRMS, and TGA–DSC studies. X-ray diffraction analysis established the molecular topology of the desired compound. The molecule showed promising energetic performance with a good oxygen balance (−31.6%), high positive heat of formation (+679.8 kJ mol−1), and high detonation pressure (P = 29.6 GPa) and velocity (Dv = 8356 m s−1), which are close to those of PETN, superior to those of HNS, and surpass those of TNT. Hirshfeld surface analysis gives insights into the molecule's sensitivity. [ABSTRACT FROM AUTHOR]

The design of novel energetic compounds constitutes a pivotal research direction within the field of energetic materials. However, exploring the intricate relationship between their molecular structure and properties, in order to uncover their potential applications, remains a challenging endeavor. Therefore, employing multi-molecule assembly techniques to modulate the structure and performance of energetic materials holds immense significance. This approach enables the creation of a new generation of energetic materials, fueling research and development efforts in this field. In this study, a series of coordination compounds are synthesized by utilizing tetranitroethide (TNE) as an anion, which possesses a high nitrogen and oxygen content. The synthesis involves the synergistic modification between metal ions and small molecule ligands. Characterization of the obtained compounds is carried out using various techniques, including single crystal X-ray diffraction, IR spectroscopy, elemental analysis, and simultaneous TG–DSC analysis. Additionally, the energy of formation for these compounds is calculated using bomb calorimetry, based on the heat of combustion. The detonation performances of the compounds are determined through calculations using the EXPLO 5 software, and their sensitivities to external stimuli are evaluated. [ABSTRACT FROM AUTHOR]

Developing environmentally benevolent and sustainable approaches is a vital objective of research in any field. By upholding these parameters and strategizing the methodology, herein we report the development of a new heterogeneous nanocatalyst based on Schiff base functionalized Pd(II) complex onto titania-coated magnetic nanoparticles [Pd@SB/Fe3O4–TiO2]. The developed catalytic system is well characterized with various techniques such as FE-SEM, TEM, XPS, XRD, TGA, BET, FTIR, VSM, CHN, EDX, and ICP-AES analysis. The catalytic activity of [Pd@SB/Fe3O4–TiO2] for the Suzuki coupling reaction to synthesize biaryls and for the hydrogenation reaction of aromatic nitro compounds to synthesize aromatic amines under sustainable reaction conditions was tested which revealed excellent results. Pd@SB/Fe3O4–TiO2 showed remarkably higher activity than the homogeneous PdCl2 and Pd(OAc)2, which might be due to the presence of electronic synergism between support and Pd. Schiff base functionalization provides excellent support to the palladium as leaching of the metal was not observed. The magnetic core of the catalyst ascertains its easy recoverability, thereby maintaining the sustainability of the reaction. The magnetic catalyst was easily separable with the help of an external magnet and showed very good recyclability for up to six cycles with no appreciable loss in catalytic efficiency. Furthermore, the reported catalyst remains unchanged even after six consecutive runs as established by the FTIR, XPS, and XRD analysis of the recovered catalyst. [ABSTRACT FROM AUTHOR]

The diverse applications of azo compounds as reagents to bring about chemical synthesis is one of the fastest-growing areas of research. It is well known that the position of the substituents has an important role in the effect of the medicinal, dye industry, thermal, and optical properties of the compounds. In this work, we limit our studies to synthesizing two new diazo dye vanillin derivatives starting from aniline. Nitro aniline compounds 10 and 12 were prepared starting from aniline, and new nitro diazo vanillin derivatives were obtained 4 and 5. Through coupling reactions with vanillin 15 via diazonium salts, 4- hydroxy-3-methoxy-5-((2,4-dinitrophenyl)diazenyl)benzaldehyde 4 was obtained from 2,4-dinitroaniline 10, while 4-hydroxy-3-methoxy-5-((2,4- 6,trinitrophenyl)diazenyl)benzaldehyde 5 resulted from 2,4,6- trinitroaniline 12. The synthesized compounds were characterized by spectroscopic methods; UV-Vis., FTIR, MS, and 1HNMR and melting point determination. The results of the reactions gave good yields of all products. [ABSTRACT FROM AUTHOR]

[Display omitted] • FeO x can optimize the catalyst structure and stabilize the catalyst performance. • FeO x more conducive to the adsorption of nitro and the desorption of the product. • FeO x can effectively mask some acid sites, inhibit the hydrolysis of CHO. • The Cu+ interface carries out the adsorption and desorption of the reactants. • CuFeAl catalyst showes best performance for converting NCH to CHO (yield: > 93 %). Nitrocyclohexane (NCH) hydrogenation to cyclohexanone oxime (CHO) is of great significance in the production of caprolactam. In this work, CuFeAl-Layered Double Hydroxide (CuFeAl-LDH) catalysts with lamellar structure were prepared by co-precipitation method and applied for NCH hydrogenation, and the promoting role of FeO x was discussed. It was found that FeO x species promote the reduction of Cu2+ and control the ratio of Cu+ to Cu0. In situ DRIFT and density-functional theory (DFT) calculation results confirm that the presence of FeO x species can act as lewis base site to reduce the acid sites and facilitate the isomerization of nitrosocyclohexane to CHO, and promotes the adsorption of NCH and the desorption of the formed CHO to prevent its further reaction to form byproducts. CuFe 0.05 Al shows the best catalytic performance of 100 % NCH conversion and 93.35 % selectivity to CHO under mild conditions. This work provides a new idea for the design of non-noble metal-based catalysts with high activity for the selective hydrogenation of nitro compounds. [ABSTRACT FROM AUTHOR]

Cleaner synthesis of amines remains a key challenge in organic chemistry because of their prevalence in pharmaceuticals, agrochemicals and synthetic building blocks. Here, we report a different paradigm for chemoselective hydrogenation of nitro compounds to amines, under mild, aqueous conditions. The hydrogenase enzyme releases electrons from H2 to a carbon black support which facilitates nitro-group reduction. For 30 nitroarenes we demonstrate full conversion (isolated yields 78 – 96%), with products including pharmaceuticals benzocaine, procainamide and mesalazine, and 4-aminophenol – precursor to paracetamol (acetaminophen). We also showcase gram-scale synthesis of procainamide with 90% isolated yield. We demonstrate potential for extension to aliphatic substrates. The catalyst is highly selective for reduction of the nitro group over other unsaturated bonds, tolerant to a wide range of functional groups, and exhibits excellent stability in reactions lasting up to 72 hours and full reusability over 5 cycles with a total turnover number over 1 million, indicating scope for direct translation to fine chemical manufacturing. The reduction of nitro-groups is a common synthetic route to amines, but biocatalytic strategies for such reactions are still being developed. In this study, the authors repurposed the hydrogenase enzyme by immobilisation on carbon black to yield a heterogeneous chemobiocatalyst for selective production of amines. [ABSTRACT FROM AUTHOR]

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The nanoconfinement approach for constructing ultra‐small nanoparticles has been effectively utilized in the development of non‐precious metal catalysts. Herein, the catalyst precursor was prepared by host‐guest assembly method, using PCN‐222 as the host and 1,1′‐bis(diphenylphosphino) ferrocene (DPPF) as the guest. After calcination, the sub‐2 nm iron oxide nanoparticles within a phosphorus‐nitrogen co‐doped carbon matrix (Fe3O4@P/N‐CDCM) was obtained. Benefiting from the nanoconfinement effect, the sub‐2 nm Fe3O4 nanoparticles were uniformly dispersed on the P/N‐CDCM matrix. As a representative application, Fe3O4@P/N‐CDCM‐600 showed remarkable catalytic activity in the reduction of various nitroaromatic compounds. Under ambient conditions, the efficient reduction of nitro compounds in aqueous solution led to excellent conversion rates (96–99 %) and selectivity (99 %) within 45 minutes. Additionally, the catalyst maintained high efficiency over 5 cycles without experiencing a noticeable decrease in activity. This work provides an innovative and cost‐effective strategy for fabricating highly dispersed non‐precious metal nanoparticles. [ABSTRACT FROM AUTHOR]

Aromatic nitro compounds are important intermediates in synthetic organic chemistry. In this work, catechol was used as raw materials, and nitro‐catechol derivatives with different alkylation substitutions were synthesized using two different synthetic routes. More than 15 new previously undescribed compounds were obtained. Each compound was meticulously characterized using a suite of physicochemical techniques, with selective compounds further analyzed via X‐Ray diffraction to ascertain their structure. These newly synthesized compounds hold significant promise as candidates for further chemical modification, which underlines their potential usefulness in the field of the fine synthesis of organic compounds. [ABSTRACT FROM AUTHOR]

A comprehensive chemical experiment was designed based on scientific research achievements to investigate the controllable preparation of LDHs (highly dispersed layer double hydroxides)-based catalysts and the catalytic reduction of nitro compounds. The experiment involves the synthesis of inorganic functional materials and catalytic materials, characterization of crystal structure, morphology, and chemical bonds of the catalytic materials, evaluation of catalytic reaction performance, and kinetic studies. By conducting this experiment, students are enabled to grasp scientific research methods, enhance their ability to think independently and explore innovative ideas, and develop skills in practical problem-solving using their knowledge of chemistry. This experiment plays a significant role in fostering the cultivation of high-quality and innovative composite talents in the new era. [ABSTRACT FROM AUTHOR]

Despite immense interest for years in Heusler alloys as magnetoelastic materials, their application in heterogeneous catalysis has only recently been explored. We report the development of highly active, robust and magnetically separable Ni2MnAl Heusler alloy nanoparticles as a heterogeneous catalyst for hydrogenation of aliphatic and aromatic nitro compounds to the corresponding amines. The easily synthesizable Ni2MnAl nanoparticles are thermally and chemically robust and exhibited excellent chemoselectivity in the hydrogenation of a range of aliphatic and aromatic nitroarenes, including those bearing functional groups sensitive to reduction, such as alkene, bromo, iodo, carbonyl and cyano, yielding the respective functionalized amines in good yields. Moreover, this solid catalyst is magnetically separable from the reaction mixture and could be recycled and reused at least 10 times without any loss in catalytic activity. The mechanism of the Ni2MnAl Heusler alloy nanoparticles catalyzed nitro reduction was studied by various spectroscopy, control experiments and kinetics. Our work opens a new avenue of developing heterogeneous earth‐abundant metal catalysis for economic and environment‐friendly synthesis of fine chemicals owing to straightforward synthesis and tunable composition of Heusler alloy nanoparticles from base‐metal precursors and their diverse structure and properties in conjunction with their thermal and chemical stability, excellent chemoselectivity, magnetic separability and recyclability. [ABSTRACT FROM AUTHOR]

Synthesis of a highly fluorescent binuclear ZnII-metallacycle (1) based on a novel Schiff base (H2L) viz. 2,7-dimethylacridine-3,6-diyl-bis(azaneylylidene)-bis(methaneylylidene)-bis(3-diethylaminophenol) is described and characterized through various spectral (FT-IR, 1H-NMR and HRMS) methods followed by structural authentication of 1 by single crystal X-ray diffraction analysis. The ZnII-metallacycle 1 is strategically incorporated with four –N(C2H5)2 groups, which enables it to exhibit excellent selectivity towards picric acid (PA) among other nitro aromatic compounds (NACs) in the form of fluorescence quenching (71%). The vital role of –N(C2H5)2 is substantiated by performing UV-vis, fluorescence, and 1H-NMR spectral and DFT studies on 1 with all NACs and comparing it with a model complex 2, which lacks the –N(C2H5)2 group. Studies revealed that the quenching involved a static and dynamic mechanism with a quenching constant (KSV) of 3.44 × 104 M and LOD of 7.62 × 10−8 M. The static pathway involved the formation of a H-bonded ground state ion pair complex of 1 and PA [1-(C2H5)2N–H+⋯O−–picrate] and the dynamic quenching is attributed to energy transfer from the excited state of 1 to the ground state of PA facilitating polar–polar resonance between them. Conclusively, 1 has been demonstrated as a significant probe, which can be employed for naked eye detection of PA in solid and liquid phases. [ABSTRACT FROM AUTHOR]

CoFe2O4@3D-Network polymers-K22.Pd was synthesized by grafting Kryptofix-22 moieties onto the surface of magnetic 3D-network polymers, followed by a reaction of the nanocomposite with Palladium (II) nitrate. The cavities of the Kryptofix-22 host material can effectively stabilize the Pd nanoparticles and prevent their aggregation and separation from the surface. Using advanced characterization techniques, such as FT-IR, BET, TGA, FE-SEM, TEM, XRD, EDX, and VSM, thorough understanding of the catalyst structure and morphology was facilitated and confirmed, its expected properties. The catalyst has been efficiently applied to Suzuki reactions and reduction of nitro compound derivatives. Its primary advantages include mild reaction conditions, high efficiency, and shorter reaction times than traditional methods. One of the greatest benefits of this catalyst is its reusability. It can be easily separated from the reaction mixture using a magnetic force and reused for up to five cycles without significant activity loss. This is important for sustainable chemistry, as it reduces waste and potentially lowers costs. [ABSTRACT FROM AUTHOR]

As a new structural motif, an interesting 3D energetic metal – framework of silver ions and 3,4-diaminofurazan, [Ag+(daf)NO3−]n, is successfully synthesized and the structure is determined by single-crystal X-ray diffraction. The effects of hydrogen bond, coordination bond, adsorption and filling interactions make this compound have a high density (2.694 g·cm−3 at 293 K). The calculated detonation velocity and the sensitivities are all comparable with trinitrotoluene (TNT). The onset decomposition temperature is equal to hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), state-of-the-art explosive. This framework provides a potential superiority of E-MOFs for energetic materials. [ABSTRACT FROM AUTHOR]

2-Pyrazoline containing benzothiazole ring 2-[1-(1,3-benzothiazol-2-yl)-5-(4-methoxyphenyl)-4,5-dihydro-1H-pyrazol-3-yl]phenol (BP) have been synthesized for the effective identification of picric acid over other competing nitro compounds using fluorescence technique. The pyrazoline BP showed quenching efficiency as high as 82% comparative to other nitro aromatics. The limit of detection and limit of quantification were found to be 1.1 μM and 3.3 μM. The possible mechanism with the quenched PA detection efficiency was based on fluorescence energy transfer and photoinduced electron transfer. Moreover, the observed results were supported by the optimized structures of the compounds using the DFT/B3LYP/6-311G/LanL2DZ method. Eventually, the pyrazoline derivative BP was further utilized for natural water samples, showing recoveries in the 87.62–101.09% and RSD was less than 3%. [ABSTRACT FROM AUTHOR]

A novel smart catalyst was developed with amino‐modified thermo‐responsive poly(N‐isopropyl acrylamide) (PNIPAM) grafts on silica‐coated magnetic nanoparticles using the conventional free radical polymerization process. By this methodology, the polymer was successfully grafted mainly onto silica‐modified iron oxide nanoparticles (Fe3O4@Si). The PNIPAM‐grafted Fe3O4@Si was then subjected to ethylenediamine treatment to produce the amino‐functionalized support (Fe3O4@Si@PNIPAM‐NH2), which was subsequently modified with carboxyl functional groups by using EDTA (ethylenediaminetetraacetic acid) to create Fe3O4@Si@PNIPAM‐NH2‐EDTA. Au nanoparticles were then decorated on this support through its two amines and four carboxylates. Different methods were used to study this novel catalyst, including inductively coupled plasma, Fourier transport infrared spectroscopy, TGA, dynamic light scattering, SEM, energy‐dispersive X‐ray analysis, vibrating sample magnetometry, XRD and elemental CHN analysis. The reduction of several aryl‐nitro derivatives demonstrated a significant catalytic activity for the as‐synthesized gold catalyst (Fe3O4@Si@PNIPAM‐NH2‐EDTA‐Au). The Au catalyst can be successfully removed from the reaction components using a magnetic field and used again in eight successive reduction reactions without significant gold leaching and loss of catalytic activity. © 2024 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Reductive amination of carbonyl compounds and nitro compounds represents a straightforward way to attain imines or secondary amines, but it is difficult to control the product selectivity. Herein, we report the selective formation of C−N or C=N bond readily manipulated through a solvent‐induced hydrogen bond bridge, facilitating the swift photocatalytic reductive coupling process. The reductive‐coupling of nitro compounds with carbonyl compounds using formic acid and sodium formate as the hydrogen donors over CdS nanosheets selectively generates imines with C=N bonds in acetonitrile solvent; while taking methanol as solvent, the C=N bonds are readily hydrogenated to the C−N bonds via hydrogen‐bonding activation. Experimental and theoretical study reveals that the building of the hydrogen‐bond bridge between the hydroxyl groups in methanol and the N atoms of the C=N motifs in imines facilitates the transfer of hydrogen atoms from CdS surface to the N atoms in imines upon illumination, resulting in the rapid hydrogenation of the C=N bonds to give rise to the secondary amines with C−N bonds. Our method provides a simple way to control product selectivity by altering the solvents in photocatalytic organic transformations. [ABSTRACT FROM AUTHOR]

The solvothermal reaction of Ln(NO3)3•6H2O (Ln = Nd, Sm, Eu, Tb, and Dy) with 9,10-bis(4-carboxylatopyridinium-1-methylene)anthracene dibromide (H2L)Br2 resulted in the formation of an isostructural series of lanthanide-based metal organic frameworks (Ln-MOFs), {[Nd(L)3/2(H2O)2]·(NO3)3·(S)}n (1), {[Sm(L)3/2(H2O)2]·(NO3)3·(S)}n (2), {[Eu(L)3/2(H2O)2]·(NO3)3·(S)}n (3), {[Tb(L)3/2(H2O)2]·(NO3)3·(S)}n (4) and {[Dy(L)3/2(H2O)2]·(NO3)3·(S)}n (5), where S denotes squeezed disordered solvent molecules and out of three nitrate ions in the voids, one nitrate is squeezed due to the high disorder. These MOFs were characterized with various techniques and single crystal X-ray analysis revealed a three dimensional (3D) (4,4,6)-connected metal organic framework with mononuclear metallic nodes in bicapped trigonal prismatic geometry. From the present series, we selected {[Sm(L)3/2(H2O)2]·(NO3)3·(S)}n (2) as a representative example for structural description and gas adsorption study whereas {[Dy(L)3/2(H2O)2]·(NO3)3·(S)}n (5) was used for the sensing of nitro compounds. All MOFs showed stability up to 200 °C. 2 demonstrates a higher CO2 uptake, despite exhibiting a low specific surface area (SABET) in N2 sorption studies. The sensing result shows that 5 act as selective sensors towards TNP with quenching efficiency greater than 99%. [ABSTRACT FROM AUTHOR]

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

Reductive amination with hydrogen is a green and atom‐efficient method to construct amines from accessible aldehydes and ketones. Flow reactors, with superior mass and heat transfer rate because of higher specific surface area, have emerged as a powerful tool to conduct reductive amination with high efficiency and selectivity. This article discusses the influence of catalysts, solvents, temperatures, additives, and substrate properties on reductive amination. Following this, a summary of research on reductive amination with hydrogen in flow reactors is provided. The investigations were classified based on distinct nitrogen sources, encompassing the use of ammonia, amines, and nitro compounds. Based on the influencing factors and reaction cases, the article analyzes the enhancement effects of temperature control, mass transfer intensification, and residence time distribution in flow reactors on the reductive amination. Finally, the article gives a conclusion by addressing challenges and prospects for further developments in this field. [ABSTRACT FROM AUTHOR]

Four coordination polymers were synthesized by two fluorescently active metal Zn/Cd(II) via pyrazinamide-based ligand [N,N′-bis[(3-pyridyl)arylphenolone]piperazine (L) and mono-/di-carboxylic acids under hydrothermal conditions, namely, [Zn(L)(HPTA)2(H2O)], [Cd(L)(HPTA)2(H2O)]∙2H2O, [Zn(L)0.5(1,4-H2BDC)(H2O)]∙H2O, [Cd(L)0.5(1,4-H2BDC)(H2O)]∙H2O and characterized by IR, PXRD and single crystal X-ray diffraction. The title complexes are from 1D "W"-shaped chains to 6-connected layers based on carboxylates and L ligands mixed linkers. The effect of metal and carboxylate on the structures of the title complexes were investigated. As fluorescent sensors for nitroaniline (NA) and nitrophenol (NOP), the title complexes show good recoverability, low LOD and high sensitivity. The applicability of [Cd(L)0.5(1,4-H2BDC)(H2O)]∙H2O was demonstrated by testing NOP and NA in three different aqueous environments (tap water, river water and wastewater). The corresponding modified detection paper and cloth were prepared and used for the recognition of NOP and NA. [ABSTRACT FROM AUTHOR]

A novel magnetic nanocomposite modified with a new branched polymer containing nitrogen-rich ligand moieties was synthesized and used to stabilize Pd nanoparticles. The resulting catalyst was characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, vibrating sample magnetometry, thermogravimetric analysis and energy-dispersive X-ray. The synthesized catalyst has been applied as an efficient catalyst in the reduction of nitro compounds to corresponding amines and reductive degradation of organic dyes such as methyl orange and methyl red. The catalyst showed high stability and reusability for 10 runs without significant loss in catalytic activity. [ABSTRACT FROM AUTHOR]

The essential oil of Aniba canelilla (Kunth) Mez (EOAC), an Amazon plant composed of a rare nitro compound, has shown scientific evidence of antifungal activity but is still unexplored against dermatophytes. The antifungal susceptibility of EOAC and its main compound, 1-nitro-2-phenylethane (NP), was evaluated against dermatophytes (Trichophyton rubrum, T. mentagrophytes and Microsporum canis), evidencing antifungal activity with an inhibitory concentration lower than 256 μg/mL. The mechanism of action was also evaluated, and it is suggested that EOAC and NP have fungicidal action in the fungal membrane, since the antifungal activity occurs through a modification of the shape of the conidial structures of the fungus, showing the permeability of the intracellular content due to the visually observed plasmolysis and cytosolic extravasation through an osmotic process. These results suggest the essential oil and its main compound are promising plant-derived alternatives for treating ungual dermatophytosis. [ABSTRACT FROM AUTHOR]

Carbon-supported single-atom catalysts were found to suffer reversible deactivation in catalytic hydrogenation, but the mechanism is still unclear. Herein, nitro compounds hydrogenation catalyzed by N-doped carbon-supported Co single atom (Co1/NC) was taken as a model to uncover the mechanism of the reversible deactivation phenomenon. Co1/NC exhibited moderate adsorption towards the substrate molecules (i.e., nitro compounds or related intermediates), which could be strengthened by the confinement effect from the porous structure. Consequently, substrate molecules tend to accumulate within the pore channel, especially micropores that host Co1, making it difficult for the reactants to access the active sites and finally leading to their deactivation. The situation could be even worse when the substrate molecules possess a large size. Nevertheless, the catalytic activity of Co1/NC could be restored via a simple thermal treatment, which could remove the adsorbates within the pore channel, hence releasing active sites that were originally inaccessible to reactants. [ABSTRACT FROM AUTHOR]

[Display omitted] 2 ' -Hydroxychalcones of 2-cinnamoyl-4-nitro-1-naphthol series were obtained by the condensation between 2-acetyl- 4-nitro-1-naphthol and benzaldehydes. The presence of the 4-positioned nitro group in the 1-hydroxy-2-naphthyl fragment contributes to the excited state intramolecular proton transfer (ESIPT) fluorescence of these 2 ' -hydroxy- chalcones in the solid state. Compound with dimethyl- amino substituent, 2-(4-dimethylaminocinnamoyl)-4-nitro- 1-naphthol, also demonstrates ESIPT in solution. [ABSTRACT FROM AUTHOR]

Carbon-supported non-precious metal catalysts with highly exposed active sites have great potential for applications in the hydrogenation reduction of nitro compounds. Herein, a strategy for the preparation of carbon-supported Mo-based catalysts (Mo@C/MC) is proposed. Protein–Mo ion networks are first coated on the surface of microsphere carbons (MC). The coated MC employed as a precursor is then pyrolyzed to produce carbon-supported Mo-based catalysts. Notably, neither pore-forming agents nor post-treatment is required in the preparation of the catalyst. The active sites tend to disperse uniformly on the surface of the carbon matrix, facilitating the exposure of the active sites of the catalyst. The as-prepared catalyst Mo@C/MC shows high conversion (>99%) and selectivity (>98%) for the hydrogenation of nitro compounds under mild reaction conditions (100 °C, 5 bar H2). [ABSTRACT FROM AUTHOR]

A general strategy for developing nitro compounds hydrogenation catalysts, involving constructing interfaces of transition-metal compounds with nitrogen-doped carbon, is proposed. The interfacial bonds in the developed catalysts can modulate the electronic structure of active sites, and hence significantly expose the active sites and enhance mass transport. Specifically, optimal Cr2O3/NC, Mo2C/NC, V2O3/NC and WOx/NC catalysts provide impressive performances with a conversion rate of 99% and a nearly 100% selectivity for hydrogenating nitro compounds. [ABSTRACT FROM AUTHOR]

Waste calcium carbide slags (CS), which are widely applied to desulfurisation, are not typically used in denitration. Herein, to well achieve waste control by waste, a facile and high-efficiency denitration strategy is developed using KOH to modify the calcium carbide slags (KCS). Various KCS samples were investigated using a series of physical and chemical characterisations. The performance test results showed that the KOH concentration and reaction temperature are the main factors affecting the denitration efficiency of KCS, and CS modified with 1.5 mol/L KOH (KCS-1.5) can achieve 100% denitration efficiency at 300°C. Such excellent removal efficiency is due to the catalytic oxidation of the oxygen-containing functional groups derived from the KCS. Further studies showed that KOH treatment significantly increased the concentration of oxygen vacancies, nitro compounds, and basic sites of CS. This study provides a novel strategy for the resource utilisation of waste CS in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

With the demand of develop outstanding‐performance energetic materials, 1‐(dinitromethyl)‐4,4',5,5'‐tetranitro‐1H,1'H‐2,2'‐biimidazole (DNM–TNBI) emerged as a great contender (D: 9102 m ⋅ s−1; P: 37.6 GPa). However, the relatively poor thermal stability (Td: 142 °C) limits its practical application. In this study, DNM–TNBI as a host molecule to synthesize two new energetic open–framework materials by effectively coordinated with different cations. Their supramolecular structures were investigated and indicated that [DNM–TNBI2−][2NH4+] and [DNM–TNBI2−][2K+] can be classified as a new energetic hydrogen–bonded ammonium framework (EHAF) and an energetic metal organic framework (EMOF). Meanwhile, their thermal stabilities are higher than that of DNM–TNBI and have satisfactory detonation performance ([DNM–TNBI2−][2NH4+], D: 8050 m ⋅ s−1, P: 26.4 GPa; [DNM–TNBI2−][2K+], D: 8301 m ⋅ s−1, P: 30.8 GPa). [ABSTRACT FROM AUTHOR]

Poly‐stoichiometry of hydrated phases is relatively uncommon for organic materials and extended libraries of such species adopting different aqua‐to‐substrate ratios are still rare. The kinetically controlled higher hydrates could be particularly interesting for their structural relationships, which presumably may imprint some features of the substrate/substrate and aqua/substrate bonding in solutions, and provide insights into the nucleation stage. Two metastable high hydrates are prepared by crash crystallization. The crystal structures of 3,3′,5,5′‐tetranitro‐4,4′‐bipyrazole tetrahydrate, C6H2N8O8·4H2O, (1), and 3,3′,5,5′‐tetranitro‐4,4′‐bipyrazole pentahydrate, C6H2N8O8·5H2O, (2), are intrinsically related to the previously reported anhydrate and monohydrate, while displaying natural evolution of the patterns upon progressive watering. The accumulation of the water molecules causes their clustering, with the generation of one‐dimensional tapes and two‐dimensional layers in the genuine channel hydrates (1) and (2), respectively, versus the pocket hydrate structure of C6H2N8O8·H2O. The hydration primarily affects the pyrazole sites. It conditions the emergence of N—H...O and O—H...N hydrogen bonds, which is a destructive factor for pyrazole/pyrazole N—H...N hydrogen bonding. At the same time, extensive noncovalent interactions of the organic molecules, namely, lone pair–π‐hole O...N interactions of the NO2/NO2 and NO2/pyrazole types, are more competitive to the hydrogen bonding and the motifs of mutual organic/organic stacks remain intact with the increase in hydration. These trends agree with the results of Hirshfeld surface analysis. The contributions of the contacts involving H atoms are increased in line with the growing number of water molecules, while the fraction of O...N/N...O (NO2) contacts is nearly invariant. One may postulate the significance of the lone pair–π‐hole interactions to the aggregation of nitro species in solutions and their relevance for the sebsequent development of the solid‐state patterns through nucleation. [ABSTRACT FROM AUTHOR]

The review is devoted to the key achievements of the Laboratory of Chemistry of Nitro Compounds at the Zelinsky Institute of Organic Chemistry of the Russian Academy of Sciences since its founding by Academician of the Russian Academy of Sciences V. A. Tartakovsky in 1971. The main attention is paid to the structural factors affecting the stability of polynitrogen-oxygen systems (PNO systems), design rules for new stabilized PNO systems, and new synthetic methods towards such systems. The synthesis of dinitramide salts, 1,2,3,4-tetrazine 1,3-dioxides, nitro-NNO-azoxy compounds, and other new classes of PNO systems is considered in detail. The advances in synthesis of new types of N-nitroamines are also considered. [ABSTRACT FROM AUTHOR]

Based on the explosive nature and harmful effects of nitro-based explosive materials on living beings and the environment, it is extremely important to develop luminescence-based probe molecules for their detection with excellent selectivity and sensitivity. Two AIPE (aggregation-induced phosphorescence emission)-active iridium(III) complexes (M1 and M2) were developed for the sensitive detection of TNT in both contact and non-contact modes. The aggregate solutions of both complexes (M1 and M2 in THF/H2O, 1/9 by volume) detected TNT at the pico-molar (pM) level. These complexes showed greatly enhanced emission intensity while embedded in a PMMA(polymethyl methacrylate) matrix film. The amplified quantum efficiency, improved phosphorescence lifetime, and enhanced porous network of M2-PMMA composite helps to improve the sesitivity of TNT vapor detection. Interestingly, the sensitivity of the detection of TNT by the M2 complex was significantly improved (5-fold) in a PMMA-incorporated complex (CP) with an observed limit of detection (LOD) of 12.8 ppb. From the BET analysis of CP, it was observed that the mesoporous network of CP has an average pore diameter of 8.52 nm and a surface area of 2.03 m2 g−1. The porous network of CP assists in trapping TNT vapor in a polymeric network containing an electron-rich probe (iridium(III) complex, M2), which helps to effectively trap TNT, thus enhancing electronic communication. As a result, significant emission quenching was observed. [ABSTRACT FROM AUTHOR]

This study introduces a novel catalyst designated as 2.6% Co/MXene, comprising cobalt (Co) nanoparticles supported by MXene. The synthesis of the 2.6% Co/MXene catalyst involved direct pyrolysis of a composite material, composed of a Co/Zn bimetal metal–organic framework and MXene. Catalytic transfer hydrogenation of functionalized nitro compounds into the corresponding formamides employed formic acid as both the hydrogen donor and formylation agent, demonstrating remarkable activity and selectivity. Control experiments validated that Co nanoparticles served as the active sites for reductive transformation. Systematic characterization and comprehensive experiments have confirmed that the superior catalytic performance of the 2.6% Co/MXene catalyst can be attributed to the uniform distribution of Co nanoparticles, a high density of basic sites, and the 3D porous architecture of the MXene support. Furthermore, the 2.6% Co/MXene catalyst exhibited excellent recyclability, preserving its catalytic activity and selectivity across four consecutive cycles. [ABSTRACT FROM AUTHOR]

Reducing nitro compounds to amines is a fundamental reaction in producing valuable chemicals in industry. Herein, the synthesis and characterization of a zirconium metal‐organic framework‐supported salicylaldimine‐cobalt(II) chloride (salim‐UiO‐CoCl) and its application in catalytic reduction of nitro compounds are reported. Salim‐UiO‐Co displayed excellent catalytic activity in chemoselective reduction of aromatic and aliphatic nitro compounds to the corresponding amines in the presence of phenylsilane as a reducing agent under mild reaction conditions. Salim‐UiO‐Co catalyzed nitro reduction had a broad substrate scope with excellent tolerance to diverse functional groups, including easily reducible ones such as aldehyde, keto, nitrile, and alkene. Salim‐UiO‐Co MOF catalyst could be recycled and reused at least 14 times without noticeable losing activity and selectivity. Density functional theory (DFT) studies along with spectroscopic analysis were employed to get into a comprehensive investigation of the reaction mechanism. This work underscores the significance of MOF‐supported single‐site base‐metal catalysts for the sustainable and cost‐effective synthesis of chemical feedstocks and fine chemicals. [ABSTRACT FROM AUTHOR]

Organic peroxides are explosive compounds that are applied as disinfectants, bleaching agents, and as initiators for polymer synthesis because of their high reactivity. Traditional homogeneous processes with H2SO4 catalyst produce salts, either in the neturalization step after reaction or due to the foramtion of tert‐butyl hydrogen sulphate, that must be disposed of, which introduces cost and represents an environmental burden. Here, we devised a flow chemistry approach to oxidize tert‐butyl alcohol (TBA) to tert‐butyl hydroperoxide (TBHP) over various heterogeneous catalysts. Under acidic conditions, TBHP is the main product and di‐tert‐butyl peroxide (DTBP) and peroxy‐ketal are by‐products. The most active catalyst was Amberlyst‐15, while yield of Nafion, activated carbon, and heteropoly acids (HPA) on carbon and silica matrices was less than 1% at 70°C. In in the range of 30 to 50°C, a first order kinetic expression characterizes the tert‐butyl alcohol conversion well (R2=0.99). The reaction rate is slow and the rate constant, k40∘C, was 0.003 min−1. Above 50°C, by‐products reacted further to acetone, methane, ethane, and other compounds. [ABSTRACT FROM AUTHOR]

Dialkyl carbonates are green and versatile reagents that can be used in alkylation and alkoxycarbonylation reactions. Herein, we disclosed a reductive methoxycarbonylation of aromatic nitro compounds with dimethyl carbonate for the construction of diverse carbamates and N-methyl carbamates. Using Mo(CO)6 as a multiple promoter, different nitroarenes were smoothly transformed into the corresponding carbamates in yields between 27 and 94% using DMC as both solvent and reagent. It is worth noting that the choice of different bases allowed the desired products to be controlled: K3PO4 favoured the formation of carbamates as the primary product, whereas DBU facilitated the formation of N-methyl carbamates as the main product. [ABSTRACT FROM AUTHOR]

Catalytic transfer hydrogenation is a practical approach for reduction of various unsaturated compounds and an alternative to pressurised hydrogenation and traditional metal hydride reagents. Among the various hydrogen donors, biomass such as glycerol and carbohydrates received considerable attention for the reduction reactions due to their non‐toxic, eco‐friendly and renewable nature. The present review addresses the development of homogeneous and heterogeneous catalysts for the transfer hydrogenation of carbonyl compounds, alkenes, alkynes, nitro compounds, CO2 etc. using glycerol and carbohydrates as potential hydrogen donors. [ABSTRACT FROM AUTHOR]

Synthesis and manufacturing of metal–organic framework derived carbon/metal oxide nanomaterials with an advisable porous structure and composition are essential as catalysts in various organic transformation processes for the preparation of environmentally friendly catalysts. In this work, we report a scalable synthesis of sulfur-doped porous carbon-containing copper oxide nanoparticles (marked CuxO@CS-400) via direct pyrolysis of a mixture of metal–organic framework precursor called HKUST-1 and diphenyl disulfide for aromatic nitro compounds reduction. X-ray diffraction, surface area analysis (BET), X-ray energy diffraction (EDX) spectroscopy, thermal gravimetric analysis, elemental mapping, infrared spectroscopy (FT-IR), transmission electron microscope, and scanning electron microscope (FE-SEM) analysis were accomplished to acknowledge and investigate the effect of S and CuxO as active sites in heterogeneous catalyst to perform the reduction-nitro aromatic compounds reaction in the presence of CuxO@CS-400 as an effective heterogeneous catalyst. The studies showed that doping sulfur in the resulting carbon/metal oxide substrate increased the catalytic activity compared to the material without sulfur doping. [ABSTRACT FROM AUTHOR]

Herein, a novel composite of g‐C3N4 and silver nanoparticles(g‐C3N4@Ag) with enhanced bifunctional catalytic activity through chemical etching is reported. A kind of g‐C3N4@Ag composite by one‐pot route, then treated the product with sodium borohydride (NaBH4) solution for a certain time is first synthesized. The property and morphology of the g‐C3N4@Ag composite changed greatly after the treatment. Compared with the pristine g‐C3N4@Ag composite, the NaBH4‐etching endowed g‐C3N4@Ag composite (RACN) with smoother two‐dimensional plane structure, as well as an extension of the conjugate system which originating from the stronger chemical connection between the Ag nanoparticles and g‐C3N4. Furthermore, research results indicated that the RACN showed superior broad‐spectrum catalytic performance for the reduction of aromatic nitro compounds, and the catalytic efficiency of the RACN is enhanced dozens of times by the treatment. Moreover, the photocatalytic activity of the RACN is also greatly improved. This discovery provides an efficient and facile method toward the enhancement of catalytic activity of semiconductor and metal nanoparticle composites by chemical etching. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of amines using highly efficient nickel phosphide NP supported on activated carbon catalyst under environmentally benign conditions. • Transfer hydrogenation of nitroarenes were conducted in mild conditions i.e., 70 °C for 2 h to get 93 % yield. • Developed reaction protocol is applicable to wide range of aromatic substrates resulting in high yields. • Structural activity relationship and mechanistic studies were performed for transfer hydrogenation of nitroarenes. Metal phosphides are promising catalysts for hydrogenation reactions due to their unique ability to generate active hydrogen species which are essential for desired reactions. In this work, the hydrogenation potential of nickel phosphide (Ni 2 P) is explored for the transfer hydrogenation of aromatic nitro compounds using hydrazine hydrate as hydrogen source. The Ni 2 P was supported on activated carbon (AC) to facilitate highly exposed active reaction sites. The as-synthesized Ni 2 P-AC catalyst showed excellent catalytic potential for the hydrogenation of nitro compounds to corresponding amines with 100% conversion efficiency and resulted in excellent yields. The reaction conditions were optimized by varying different reaction parameters, such as time, temperature, solvents, catalyst amount and hydrogen sources. The developed reaction protocol is highly selective for nitro compounds having reduction susceptible functional groups like -Cl, -Br, –CHO, etc. The structure–activity relationship of the Ni 2 P-AC was also examined which suggested that both acidic and basic sites present in Ni 2 P-AC catalyst plays crucial role in hydrogenation reaction. Besides, an in-depth insight into the reaction mechanism illustrates that the reaction proceeds via N -phenyl hydroxylamine as the reaction intermediate. In addition, decent recyclability and stability of Ni 2 P-AC catalyst demonstrates its highly versatile nature for potential large-scale applications. The use of highly efficient Ni 2 P-AC catalyst for hydrogenation reactions can lead the way towards sustainable and effective industrial organic catalysis. [ABSTRACT FROM AUTHOR]