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As a result of its high reactivity, furan-2(3H)-one derivative 2 can be selected as a versatile and suitable candidate for building of novel nitrogen heterocyclic compounds. Consequently, furan-2(3H)-one derivative 2 and some nitrogen nucleophiles were utilized as starting materials for the formation of new pyridazinone and pyrrolone derivatives bearing naphthalene moiety. The continuous buildup of insecticide resistance is the main obstacle facing pest control measures. Pyrrole-based insecticides are a favourable choice due to their unique mode of action and no cross-resistance with traditional neurotoxic insecticides. The larvicidal activities of pyrrolone derivatives were assessed against field and laboratory strains of Culex pipiens larvae in comparison with chlorfenapyr (pyrrole insecticide). Compounds 17 (21.05 µg/mL) > 9 (22.81 µg/mL) > 15 (24.39 µg/mL) > 10 (26.76 µg/mL) > 16 (32.09 µg/mL) were most effective against lab strain of C. pipiens larvae relative to chlorfenapyr (25.43 µg/mL). While in field strain, 17 and 15 were the most toxic compounds followed by 9 > 10 > 16 > 2 with LC50 of 9.87, 10.76, 11.52, 12.68, 15.32 and 18.37 µg/mL, respectively, compared with chlorfenapyr with 14.03 µg/mL. The cytochrome P-450 monooxygenase activities were significantly increased in treated larvae of lab and field strains relative to untreated. The great variations in toxicity of the synthesized compounds were interpreted by structure-activity relationship study. The pyrrolone derivatives are effective against field and insecticide-resistant strains. Therefore, they are considered promising compounds to be integrated into pest management programs. [ABSTRACT FROM AUTHOR]

AbstractNaphthalene and its derivatives are often determined as markers of environmental pollution, although they are also recognized as crucial building blocks in many beneficial compounds. In the course of this study, a range of 1,2-disubstituted naphthalenes bearing nitro, amine, sulfonate, chlorine, and hydroxyl substituents were synthesized and characterized using several spectroscopic techniques, including FT-IR,1H NMR,13C NMR, DEPT-90, DEPT-135, DEPTq, elemental analysis, and high-resolution mass (HRMs). The NMR analysis of the aromatic hydrocarbon moiety in these compounds emphasized the impact of substituent variations on the appearance of 1H and 13C NMR signals. To resolve the issue of overlapping one-dimensional (1D) 1H NMR signals and determine the connectivity of hydrogen and carbon atoms from the aromatic naphtayl ring, we employed a “two-dimensional” experiment, using homonuclear correlation spectroscopy (2D 1H-1H COSY) and heteronuclear single quantum correlation (2D 1H - 13C HSQC) and heteronuclear multiple‐bond correlation spectroscopy (2D 1H - 13C HMBC). This work also investigated the correlation between 1H NMR signals and thin-layer chromatography (TLC) data. X-ray crystallography data validates that the presence of a specific group, not aligned coplanarly with the naphthyl ring, exerts a spatial influence on the manifestation of 1H NMR signals, alongside other electronic effects. This study will offer NMR data, providing insights into the potential applications and analyses of naphthalene derivatives across various theoretical and practical domains. [ABSTRACT FROM AUTHOR]

We report a liquid material based on an L -valine-appended pyromellitic diimide framework. This liquid adopts a room-temperature liquid with Tg at −50 °C and can dissolve naphthalene derivatives to show various photoluminescent colors. Furthermore, the on/off photoluminescence of these solutions can be controlled by heating. [ABSTRACT FROM AUTHOR]

Allyl ether naphthol resin (ANPF) was synthesized by introducing 1,5‐dihydroxynaphthalene and 2,7‐dihydroxynaphthalene into phenolic resin and was copolymerized with 4,4′‐bismaleimidodiphenylmethane resin (BDM) to obtain allyl ether naphthol‐modified bismaleimide resins (15‐ANPF‐BDM and 27‐ANPF‐BDM). The resulting thermal stability and glass transition temperature (Tg) were explored by thermogravimetric and dynamic mechanical analyses. The char yield of 15‐ANPF‐BDM at a temperature of 800°C was 46.0%. Additionally, the Tg of 15‐ANPF‐BDM was measured as 311°C, which is an increase of 44°C compared to that of c. The mechanical properties of the ANPF‐BDM/quartz fiber (Qf) composites were also investigated. The results reveal that ANPF‐BDM/Qf composites exhibit similar mechanical strength to APF‐BDM/Qf composites at room temperature. In addition, the mechanical properties of the ANPF‐BDM/ Qf composites demonstrated significant improvement in mechanical properties retained significantly improved at 200°C, with a 68% flexural strength retention and a 96% interlaminar shear retention of 15‐ANPF‐BDM/Qf composites. Thus, ANPF‐BDM/Qf composites exhibit outstanding mechanical properties at 200°C. [ABSTRACT FROM AUTHOR]

The unusual reactivity of key enamine intermediates led to the formation of 3-methylamino-2-(2-nitrobenzoyl)-4H-naphthalen-1-one as an unexpected product in an attempted synthesis of the P. aeruginosa metabolite 2-benzyl-4(1H)-quinolone. Although the synthesis of the natural product has not been successful, this methodology allows for the easy preparation of novel derivatives carrying a carboxamide moiety at the C3 position. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive overview of various methods for the synthesis of substituted naphthalene derivatives. Naphthalene is a versatile organic compound with applications in materials chemistry, electronics, and medicine. The synthesis of naphthalene involves metal-catalyzed reactions, such as palladium-catalyzed carboannulation, and yields derivatives with diverse substituents. These derivatives have medicinal importance and exhibit a wide range of therapeutic activities. The article discusses different metal-catalyzed reactions, their mechanisms, and examples of reactions. It also highlights the need for more environmentally friendly approaches to naphthalene synthesis. [Extracted from the article]

4,16‐para‐substituted [2.2]paracylophanes with naphthalene (PCP‐NAP), anthracene (PCP‐ANTH), and tetraphenylethylene (PCP‐TPE), as new through‐space conjugated dimers, were prepared by the Suzuki‐Miyaura cross‐coupling reaction of 4,16‐diboryl[2.2]paracyclophane and the corresponding bromo derivative using Pd(PPh3)4 as a catalyst and KOH as a base. The synthesized compounds were fully characterized by NMR and HR‐MS, and their photophysical and electrochemical properties were studied. The photoluminescence quantum yield of PCP‐NAP, PCP‐ANTH were determined to be 0.21, 0.50, and for PCP‐TPE in aggregated state 0.31, respectively. PCP‐TPE exhibited aggregation‐induced emission characteristics when the water fraction was greater than 50 % in THF/water mixtures. PCP‐ANTH and PCP‐TPE were also characterized by X‐ray crystallography, PCP‐ANTH crystallizes in centrosymmetric monoclinic space group C2/c and PCP‐TPE crystallizes in the centrosymmetric triclinic space group P‐1 with one molecule residing at the inversion center. The observed properties of these π‐stacked dimers were compared with respect to through‐space conjugation and conjugation length in the structure. [ABSTRACT FROM AUTHOR]

Using palladium-catalyzed arylation of (S)-2,2′-diamino-1,1′-binaphthalene (BINAM) with the halogen derivatives of naphthalene, anthracene, and anthraquinone, the corresponding N,N′-diaryl derivatives were synthesized. The dependence of the yields of the compounds on the structure of the initial halogen derivatives was shown. The synthesized compounds were studied in fluorescent enantioselective detection of amino alcohols. The synthesized derivatives demonstrate a response in the case of complex formation with some amino alcohols, but the response is most pronounced for the derivative with anthraquinone substituents. This detector can recognize enantiomers of leucinol, 2-phenylglycinol, and prolinol by different changes in the fluorescence enhancement in the presence of opposite optical isomers. In the case of 2-amino-1-propanol, fluorescence enhancement is observed only in the presence of the (S)-isomer. [ABSTRACT FROM AUTHOR]

A novel 3D nitrogen-doped porous carbon supported Fe-Cu bimetallic nanoparticles composite (Fe-Cu-N-PC) was prepared via direct pyrolysis by employing black liquor lignin as a main precursor, and it was utilized as a novel catalyst for PMS activation in degrading naphthalene. Under the optimum experimental conditions, the naphthalene degradation rate was up to 93.2% within 60 min in the Fe-Cu-N-PC/PMS system. The porous carbon framework of Fe-Cu-N-PC could facilitate the quick molecule diffusion of reactants towards the inner bimetallic nanoparticles and enriched naphthalene molecules from the solution by a specific adsorption, which increased the odds of contact between naphthalene and reactive oxygen species and improved the reaction efficiency. The quenching reaction proved that the non-free radical pathway dominated by 1O2 was the main way in naphthalene degradation, while the free radical pathway involving SO4·− and ·OH only played a secondary role. Moreover, owing to its high magnetization performance, Fe-Cu-N-PC could be magnetically recovered and maintained excellent naphthalene degradation rate after four degradation cycles. This research will offer a theoretical basis for the construction of facile, efficient, and green technologies to remediate persistent organic pollutants in the environment. [ABSTRACT FROM AUTHOR]

Aliphatic polycarbonates have been explored as environmentally benign alternatives to aromatic polycarbonates. Improvements to the glass transition temperature (Tg) of aliphatic polycarbonates have been pursued by several groups. We recently showed that attaching a pendant aromatic group to poly(TMC) can enhance the Tg. Also, we have shown that para substituents on the pendant group have an impact on the Tg. Here, we have explored the role of bulky pendant groups and the effect of substituent position on the pendant aromatic ring. We prepared novel naphthalene‐derived poly(TMC)s as well as 2‐Br‐substituted poly(PhTMC). The 2‐bromophenyl derivative showed a Tg of 69.5 °C which represents a nominal increase in comparison to the 4‐bromo derivative that we reported earlier. This suggests that the position of the substituent does not have a critical impact on Tg. With naphthalene derivatives, the increase in steric bulk led to an increase in Tg. Increase of chain length beyond fifty monomer units had a minimal impact on Tg. Finally, when 4‐bromonaphthyl moiety was the pendant group, we observed a Tg of 97 °C. This demonstrates that Tg can be varied significantly by modifying the pendant groups. We have also shown that the 1,3‐diols used in our polymer are non‐cytotoxic. [ABSTRACT FROM AUTHOR]

A molecular belt incorporating naphthalene moieties, featuring an ellipsoidal cavity, was precisely engineered through bottom–up synthesis. Its pre-arranged geometry exhibits excellent complementarity to fullerene C70, resulting in remarkable selective binding ability (K = 1.3 × 106 M−1) for C70 compared to C60 (K = 176 M−1), forming a 1 : 1 complex. This superiority was unequivocally demonstrated by the single crystal structure of the complex, which revealed outstanding concave–convex shape complementarity between the two components. This highlights the potential application of molecular belts in the purification and separation of fullerenes. [ABSTRACT FROM AUTHOR]

A molecular belt incorporating naphthalene moieties, featuring an ellipsoidal cavity, was precisely engineered through bottom–up synthesis. Its pre-arranged geometry exhibits excellent complementarity to fullerene C70, resulting in remarkable selective binding ability (K = 1.3 × 106 M−1) for C70 compared to C60 (K = 176 M−1), forming a 1 : 1 complex. This superiority was unequivocally demonstrated by the single crystal structure of the complex, which revealed outstanding concave–convex shape complementarity between the two components. This highlights the potential application of molecular belts in the purification and separation of fullerenes. [ABSTRACT FROM AUTHOR]

Naphthalene (Nap) and its derivatives, including 1-methylnaphthalene (1-MN) and 2-methylnaphthalene (2-MN), serve as prominent intermediate volatile organic compounds (IVOCs) and contribute to the formation of secondary organic aerosol (SOA). In this study, the Community Multiscale Air Quality (CMAQ) model coupled with detailed emissions and reactions of these compounds was utilized to examine their roles in the formation of SOA and other secondary pollutants in the Yangtze River Delta (YRD) region during summer. Significant underestimations of Nap and MN concentrations (by 79 % and 85 %) were observed at the Taizhou site based on the model results using the default emissions. Constrained by the observations, anthropogenic emissions of Nap and MN in the entire region were multiplied by 5 and 7, respectively, to better capture the evolution of pollutants. The average concentration of Nap reached 25 ppt (parts per trillion) in the YRD, with Nap contributing 4.1 % and 8.1 % (up to 12.6 %) of total aromatic emissions and aromatic-derived secondary organic carbon (SOC), respectively. The concentrations of 1-MN and 2-MN were relatively low, averaging 2 and 5 ppt, respectively. Together, they accounted for only 2.4 % of the aromatic-derived SOC. The impacts of Nap and MN oxidation on ozone and radicals were insignificant at regional scales but were not negligible when considering daily fluctuations in locations with high emissions of Nap and MN. This study highlights the significant roles of Nap and MN in the formation of SOA, which may pose environmental risks and result in adverse health effects. [ABSTRACT FROM AUTHOR]

The development of low-cost and safe hydrogen storage systems is a priority when creating new energy sources. Storing hydrogen in chemical compounds in which it occurs naturally is the only alternative. Aromatic hydrocarbons, capable of reversible hydrogenation–dehydrogenation reactions, are of the greatest interest among regenerated hydrogen-containing compounds and can be used for hydrogen storage. Naphthalene, its methyl derivatives and the products of hydrogenation have the high storage density among the aromatic hydrocarbons (up to 7.3 wt%) which make it the extremely perspective as liquid hydrogen storage carriers. Therefore, the synthesis of the compounds with the higher added value (as decalin) is a highly important from scientific point of view. However, for the building up of "ideal" chemical system of hydrogen storage the development of effective catalytic systems with the composition and morphology adopted to the structure of aromatic substrate is highly needed. This review discusses the role of the metal in the catalytic hydrogenation of naphthalene and its derivatives for hydrogen storage. [Display omitted] • Chemical hydrogen storage in liquid organic hydrogen carriers is studied. • The supported metal role in the hydrogenation of naphthalene's is discussed. • The non-noble metal doped with small amounts of noble metal are promising catalysts. [ABSTRACT FROM AUTHOR]

Over the past decade, significant progress has been made in the direct C-H acylation of naphthalenes, occurring at the α or β positions to yield valuable ketones through Friedel-Crafts acylation or transition-metal-catalysed carbonylative coupling reactions. Nevertheless, highly regioselective acylation of naphthalenes remains a formidable challenge. Herein, we developed a nickel-catalysed reductive ring-opening reaction of 7-oxabenzonorbornadienes with acyl chlorides as the electrophilic coupling partner, providing a new method for the exclusive preparation of β-acyl naphthalenes. [ABSTRACT FROM AUTHOR]

We showcase herein organic crystalline solid solutions (CSSs) based on the simplest polycyclic aromatic hydrocarbon (PAH) scaffold, naphthalene, stabilized by dispersion forces induced by adamantane substitution. High thermal stability of the host and guest molecules synthesized by cross‐coupling of dibromonaphthalene derivatives and 4‐(1‐adamantyl)phenyl boronic ester enabled formation of crystals by sublimation. We could generate binary monocrystalline solid solution systems proven by X‐ray crystallography, the first system of designed CSSs stabilized exclusively via dispersion forces with structural evidence. These observations are additionally supported by lattice energy calculations and spectroscopic examinations. For the generation of CSSs, it is of utmost importance that the host and guest molecules have similar lattice energies and spatial compatibility. We anticipate that the thermostable organic CSS design demonstrated herein would be beneficial for functional materials and further investigation towards materials with unique properties. [ABSTRACT FROM AUTHOR]

The present study evaluated the effects of acid and organosolv pretreatments on the analytical fast pyrolysis products of green coconut fiber (GCF), a residue from the coconut processing industry. Untreated and pretreated biomasses were characterized by chemical composition, crystallinity, functional groups, and thermal stability. Fast pyrolysis experiments were carried out in a pyrolysis–gas chromatography-mass spectrometry (Py-GC/MS) apparatus in the absence and presence of HZSM-5 zeolite. Both pretreatments effectively removed hemicellulose, ashes, and extractives, increasing cellulose content and crystallinity. Organosolv pretreatment with glycerol also promoted the reduction of Klason lignin in GCF from 35.68 to 28.68%, while acid pretreated GCF had 45.51% Klason lignin. In pyrolysis without a catalyst, acid and organosolv pretreatments reduced the selectivity of C1-C4 compounds from 47.05% to 23.22% and 25.31%, respectively. The generation of phenol and methylphenols from GCF increased after acid and organosolv pretreatments. With the aid of HZSM-5, high benzene-toluene-ethylbenzene-xylene (BTEX) values were obtained using acid-pretreated GCF (72.0%) and organosolv-pretreated GCF (71.1%) when compared to experiments with untreated GCF (64.9%). Pyrolysis vapors from organosolv-pretreated GCF also have a low selectivity of naphthalenes (9.63%). Thus, chemical pretreatments ratified their role in improving the bio-oil, raising the GCF as an opportunity to produce phenol or monoaromatics via fast pyrolysis. [ABSTRACT FROM AUTHOR]

Biomass gasification process generates the residual tar, which in turn exerts some negative influence on biomass gasification system. To reduce this harmful influence, an evaluation of the tar properties during the biomass gasification was studied. The chemical composition and pyrolysis behavior of biomass tar were investigated. The complex chemical composition of the tar, which includes phenol derivatives, naphthalene derivatives, other macromolecular aromatic compounds, furans, and other compounds (carbon number from 7 to 14), was established by gas chromatography-mass spectrometry technique. Thermogravimetric analysis was performed with two heating rates (10°C/min and 20°C/min), and Coats-Redfern method was applied to assess the kinetic parameters, i.e., the activation energy (E) and pre-exponential factor (A) of tar thermochemical decomposition. The results showed that the main degradation of tar is a two-step process, including a volatilization step at lower temperatures (<105°C) and a pyrolysis step at higher temperatures (105°C-380°C). The application of the Coats-Redfern method revealed a variation trend of the activation energy during the decomposition of tar in a non-isothermal model. It shows that high temperature is more conducive to tar pyrolysis. By adjusting the temperature to control the generation and removal of tar, new approaches are provided for designing and optimizing biomass gasification systems. [ABSTRACT FROM AUTHOR]

Photochemical and photocatalytic oxidation of naproxen (NPX) with UV-A light and commercial TiO2 under constant flow of oxygen have been investigated. Adsorption experiments indicated that 90% of the solute remained in the solution. Combined chemical analysis of samples on the photochemical degradation indicated that NPX in an aqueous solution (20 ppm) is efficiently transformed into other species but only 18% of the reactant is mineralized into CO2 and water after three hours of reaction. Performing the photocatalytic oxidation in the presence of TiO2, more than 80% of the organic compounds are mineralized by reactive oxidation species (ROS) within four hours of reaction. Analysis of reaction mixtures by a combination of analytical techniques indicated that naproxen is transformed into several aromatic naphthalene derivatives. These latter compounds are eventually transformed into polyhydroxylated aromatic compounds that are strongly adsorbed onto the TiO2 surface and are quickly oxidized into low-molecular-weight acids by an electron transfer mechanism. Based on this and previous studies on NPX photocatalytic oxidation, a unified and complete degradation mechanism is presented. [ABSTRACT FROM AUTHOR]

In this study, two novel C8‐functionalization methods of 1‐carbonylnaphthalenes were developed. Leveraging iodonium triflates as coupling partners, we disclose palladium‐catalyzed C8‐fluoroalkylation and C8‐fluoroalkenylation processes. These protocols exhibit broad applicability across diverse naphthalene derivatives, owing to carbonyl directing groups at the C1 position which can be retained for subsequent applications or selectively removed, enhancing the versatility of the developed methodologies. [ABSTRACT FROM AUTHOR]

Inter-molecular π–π stacking interactions of aromatic systems play crucial roles in functional nanomaterials and therapeutics. Herein, we developed a series of novel 8-hydroxyquinoline-polycyclic aromatic hydrocarbon (PAH) conjugates (PH1–PH3) by coupling 8-hydroxyquinoline with a series of PAHs such as naphthalene, anthracene, and pyrene. A second series of quinoline-PAH derivatives (PD1–PD3) has also been developed by sulfonating the quinoline –OH of the first series. Crystallographic analyses of these compounds revealed exciting structural and supramolecular features. Supramolecular analyses of PH series compounds revealed that the crystal packing interactions in these compounds are dominated by intermolecular C–H⋯O and C–H⋯π interactions, in which the C–H⋯O interactions lead to the formation of zig-zag 1D chains in the crystal lattice, which are interconnected to a 3D network by various intermolecular C–H⋯π interactions. Compared to the PH series, the supramolecular interactions in the PD series are dominated by π–π and C–H⋯π interactions. In these compounds, two adjacent V-shaped molecules are arranged in a dimeric fashion such that one arm of the V-shaped molecule is packed within the cleft formed by the arms of the other. In the crystal lattice of PD series compounds, such dimers are interconnected through π–π interactions into 1D chains/2D sheets, which are further interconnected into 2D/3D networks through additional C–H⋯π/π–π stacking interactions. The preliminary cytotoxicity properties of PH and PD series compounds were evaluated using human hepatocellular carcinoma cells (HepG2 cells). It was observed that the presence/absence of –OH group on the quinoline ring and the size of the PAH ring play significant roles in determining the cytotoxicity of these compounds. The PH series compounds with an –OH substituent on the quinoline ring exhibited comparatively better cytotoxicity (IC50 values in the range 8.03–11.72 μM) than the PD series compounds (IC50 values in the range 9.48–38.16 μM) with sulfonated quinoline moiety. The compound bearing pyrene PAH and –OH substituent on the quinoline ring exhibited the best cytotoxicity (IC50 = 8.03 μM) among all the compounds tested. The present study, therefore, shows that the quinoline-PAH conjugates can exhibit interesting structural and supramolecular properties along with appreciable cytotoxic effects. Further, these properties could be fine-tuned by changing the size of the PAH ring and the substituent on the quinoline ring. [ABSTRACT FROM AUTHOR]

Atenolol β‐blocker drug (ATN) to treat hypertension and cardiovascular disorders such as angina pectoris is manufactured commercially in a racemic form, while only its (S)‐enantiomer shows selective β1‐blocking activity. Here, a new axially chiral thiolated naphthalene diimide derivatives (HS‐BIN‐NDI) for the rapid, simple, and sensitive detection of ATN enantiomers is presented. The Surface Plasmon Resonance (SPR) and Atomic Force Microscopy (AFM) experiments show that interactions between a chiral selector and a chiral analyte occur only when their configurations are opposite. The extensive computational simulations support this finding. The association coefficient determined by SPR is high (105‐106 M−1 s−1) and indicates that the interactions are electrostatic. The analytical utility of atropisomeric HS‐BIN‐NDIs is proven, and the voltammetric sensors designed to determine ATN enantiomers are constructed. The developed sensors are characterized by a wide analytical operating range from 5.0·10−3 to 1.0 µm, nanomolar detection limit, high selectivity, and a long lifetime. Several additives like urea, creatinine, glucose, human albumin, and hemoglobin do not affect ATN sensing. [ABSTRACT FROM AUTHOR]

The development of innovative antifungal medications to address the issues of indiscriminate antifungal use contributes to certain antifungal drug resistance. To tackle this issue, we have designed and synthesized novel amino acids naphthalene scaffolds (6 a–6 i) (Scheme 1) by acid amine coupling between compound 5 and various amino acids. Moreover, we evaluated the antifungal, anti‐bacterial and antimalarial activities of synthesized derivatives. Among them, compounds Met (6 a), Phe (6 c), Lys (6 d), Ser (6 f), and Tyr (6 i) expressed excellent antifungal activity at a minimum inhibitory concentration (MIC) value of 250 μg/mL against Candida albicans compared to standard drug griseofulvin (500 μg/mL). The antibacterial assay results showed that compound Met (6 a) exhibited effective antibacterial activity at MIC value at 50 and 62.5 μg/mL against Streptococcus pyogenes and Pseudomonas aeruginosa respectively, and compound Trp (6 g) showed very good antibacterial activity at MIC 62.5 μg/mL against Staphylococcus aureus. The antimalarial activity of synthesized compoundsVal (6 b) and Lys (6 d) showed moderately active with mean IC50 of 0.69 and 0.47 μg/mL, respectively compared with standard drug quinine (IC50=0.26 μg/mL). Also, a molecular docking study was performed to demonstrate the binding energy of synthesized scaffoldswith effective interaction with various proteins. The compound Met (6 a) showed that the highest binding affinity (binding energy: −7.1 kcal/mol) which interacted more effectively with VAL 120 (2.90 Å). [ABSTRACT FROM AUTHOR]

We present the synthesis of a new oxacalix[4]arene system, DMANSOC, wherein two 5-(dimethylamino)-1-naphthalene sulfonamide subunits are attached to the lower rims of the basic oxacalix[4]arene platform. Extensive spectrophotometric studies were conducted to investigate the selectivity and sensitivity of DMANSOC towards nitroaromatic explosives. Detailed analysis of spectrophotometric data, utilizing techniques such as Stern-Volmer, Benesi-Hildebrand, Job's plot, and interference study, unequivocally demonstrated the effectiveness of DMANSOC as a highly efficient fluorescent sensor for 2,4,6-trinitrophenol explosive (TNP) detection in an aqueous medium. The sensor exhibited a linear concentration range of 7.5 μM to 50 μM, with a low detection limit of 4.64 μM and a high binding affinity of 2.45 × 104 M towards TNP. Furthermore, the efficiency of the sensor in environmental samples contaminated with TNP was evaluated, yielding excellent recovery rates. Complementary DFT calculations and molecular dynamics simulations were performed to elucidate the mechanism behind the selective fluorescence quenching of DMANSOC in the presence of TNP. [ABSTRACT FROM AUTHOR]

Although the synthesis of vinyl triflates has a long history, the synthesis of vinyl bis(perfluoroalkanesulfonyl)imides has not been reported yet. Here, we report a simple synthetic route to vinyl bis(perfluoroalkanesulfonyl)imides that does not require any additives. The stereoselectivity originates from the steric hindrance between the aryl group and the imide. The reaction proceeds chemoselectively, and subsequent cyclization provides the 1‐amino‐3‐aryl naphthalene derivatives. [ABSTRACT FROM AUTHOR]

The reactions of cage‐opened C60 derivatives with aromatic diamines are known to cause an orifice‐enlargement in association with incorporating extended π‐systems. The present work focuses on 1,2‐, 2,3‐, and 1,8‐diaminonaphthalenes for the synthesis of a series of naphthalene‐fused fullerene derivatives. For the former two, orifice enlargement proceeded by cleaving two C=C bonds to afford an opening with a ring‐atom count of 20, in which the naphthalene moiety was fused by a pyrazine ring. For the reaction with 1,8‐diaminonaphthalene, only one C=C bond was cleaved to give a 17‐membered‐ring opening where the diaminonaphthalene moiety was fused by a pyrimidine ring. [ABSTRACT FROM AUTHOR]

Today, new energy sources alternative to fossil fuels are needed to meet the increasing energy demand. It is becoming increasingly important to constitute new energy sources from waste biomass through the liquefaction process. In this study, walnut shells (WS) were liquefied catalytically and non-catalytically under different parameters using the liquefaction method. In this process, the effect of silica fume/nano zero-valent iron (SF/NZVI) catalysts on the conversion rates was investigated. The catalyst was synthesized by reducing NZVI using a liquid phase chemical reduction method on SF. The SF/NZVI catalyst was characterized by scanning electron microscopy- energy dispersive X-ray (SEM–EDX), transmission electron microscope (TEM), Brunauer–Emmett–Teller (BET), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) analysis. The effect of various process parameters on the liquefaction process was investigated. In this context, the reaction temperature ranged from 300 to 400 °C, the solid/solvent ratio ranged from 1/1 to 1/3, the reaction time ranged from 30 to 90 min, and the catalyst concentration ranged from 1 to 6%. According to the results obtained, the most suitable operating conditions for non-catalytic experiments in liquefaction of WS were found to be temperature of 400 °C, reaction time of 60 min, and solid/solvent of 1/3. In catalytic conditions, the optimum values were obtained as temperature of 375 °C, reaction time of 60 min, solid/solvent ratio of 1/3, and catalyst concentration of 6%. The highest total conversion and (oil + gas) % conversion were 90.4% and 46.7% under non-catalytic conditions and 90.7% and 62.3% under catalytic conditions, respectively. Gas chromatography/mass spectrometry (GC/MS) analysis revealed the bio-oil was mainly composed of aromatic compounds (benzene, butyl-, indane and their derivatives,) and polyaromatic compounds (naphthalene, decahydro-, cis-, naphthalene, 1-methyl-.). The aim of increasing the quantity and quality of the light liquid product in the study has been achieved. [ABSTRACT FROM AUTHOR]

Mesophase pitch is usually prepared by radical polymerization or catalytic polymerization from coal tar, petroleum, and aromatic compounds, and the catalytic synthesis of mesophase pitch from pure aromatic compounds is more controllable in the preparation of high-quality mesophase pitch. However, the corrosive and highly toxic nature of the catalyst has limited the further development of this method. In this study, mesophase pitch was synthetized using ethylene tar and naphthalene as raw materials and boron trifluoride diethyl etherate as a catalyst. The effect of the catalytic reaction on the structure and properties of the mesophase pitch was investigated. The results show that naphthalene plays an important role in the mesophase content and reaction pressure (from above 6 MPa to 2.35 MPa). Mesophase pitch with fine-flow texture can be prepared by introducing more methylene groups, naphthenic structures, and aliphatic hydrocarbons during synthesis. Carbon fibers prepared from mesophase pitch show a split structure, and the thermal conductivity is 730 W/(m·K). This work provides theoretical support for lower toxicity and causticity and for reaction-controlled technology for the synthesis of high-purity mesophase pitch. [ABSTRACT FROM AUTHOR]

Naphthalene is the most abundant polycyclic aromatic hydrocarbon (PAH) in vehicle emissions and polluted urban areas. Its atmospheric oxidation products oxygenated compounds potentially harmful for health and/or contributing to secondary organic aerosol (SOA) formation. Despite its impact on air quality, its complex structure and lack of data mean that no detailed scheme of naphthalene gaseous oxidation for SOA formation and speciation has yet been established. This study presents the construction of the first near-explicit chemical scheme for naphthalene oxidation by OH including kinetic and mechanistic data. The scheme redundantly represents all the classical steps of atmospheric organic chemistry (i.e. oxidation of stable species, peroxy radical formation and reaction and alkoxy radical evolution) integrating therefore fragmentation or functionalization pathways and the influence of NOx on secondary compound formation. Missing kinetic and mechanistic data were estimated using structure-activity relationships (SARs) or by analogy with existing experimental or theoretical data. The proposed chemical scheme involves 392 species (237 stable species, including 93% of the major molar masses observed in previous experimental studies) and 503 reactions with products. A first simulation reproducing experimental oxidation in oxidation flow reactor under high NOX conditions shows a simulated SOA mass in the same order of magnitude as experimentally observed, with an error of -12%. [ABSTRACT FROM AUTHOR]

The generation of open‐shell intermediates under mild conditions has opened broad synthetic opportunities during this century. However, these reactive species often require a case specific and tailored tuning of experimental parameters in order to efficiently convert substrates into products. We report a general approach that can overcome these ubiquitous limitations for several visible‐light promoted energy‐transfer processes. The use of either naphthalene (5–20 equiv.) or simple binaphthyl derivatives (10–30 mol %) greatly increases their efficiency, giving rise to a new strategy for catalysis. The trend is consistent among different media, photocatalysts, light sources and substrates, allowing one to improve existing methods, to more easily optimize conditions for new ones, and, moreover, to disclose otherwise inaccessible reaction pathways. [ABSTRACT FROM AUTHOR]

Non‐covalent interactions such as coordination of an organolithium reagent by a directing group and steric repulsion of substituents strongly affect the halogen‐lithium exchange process. Here we present the manifestation of the "buttressing effect" – an indirect interaction between two substituents issued by the presence of a third group – and its influence on the ease and selectivity of the bromine‐lithium exchange and the reactivity of formed aryllithiums. The increase of the size of the "buttressing" substituent strongly affects the conformation of a NMe2 group, forcing it to hinder ortho‐bromine and thus slowing down the exchange. In naphthalene substrates bearing two bromines, this suppresses regioselectivity of the reaction. The "buttressing effect" forces formed aryllithiums to deaggregate, thus boosting their reactivity. This facilitates the decomposition via protolisys by ethereal solvents even at low temperatures and in some cases initiates fast Wurtz‐Fittig coupling. [ABSTRACT FROM AUTHOR]

Mandatory use of low-sulfur fuel according to global sulfur limit regulation has reduced the emissions of SO2 and PM significantly on ships, while it also leads to very large uncertainty on VOCs emission. Therefore, on-board test of VOCs from 9 typical cargo ships with low-sulfur fuels in China were carried out in this study. Results showed that emission factor of VOCs (EFVOCs) varied largely from 0.09 to 3.01 g kg-1 fuel, with domestic coastal cargo ships (CCSs) had the highest levels and ocean-going vessels (OGVs) the lowest. The switch of fuels from heavy fuel oil (HFO) to diesel increased EFVOCs by 48 % on average, which enhanced both O3 and secondary organic aerosol (SOA) formation potentials, especially for OGVs. Besides, the use of low-sulfur fuels for OGVs also lead to significant increase of naphthalene emission. These indicated the implementation of globally ultra-low-sulfur oil policy in the near future needs to be optimized. Moreover, aromatics were the most important common contributors to O3 and SOA in ship exhausts, which need to be controlled with priority. It was also found that benzene, toluene, and ethylbenzene ratio of 0.5:0.3:0.2 on average could be considered as a diagnostic characteristic to distinguish ship emission from other emission sources. [ABSTRACT FROM AUTHOR]

In this study, a series of ester-linked tetracarboxylic dianhydrides (TCDAs) with 2,6-naphthalene-containing longitudinally extended structures consisting of different numbers of aromatic rings (NAr = 6–8) was synthesized to obtain novel modified polyimides, poly(ester imide)s (PEsIs). These TCDAs were fully compatible with the conventional manufacturing processes of conventional polyimide (PI) systems. As an example, the PEsI film obtained from the ester-linked TCDA (NAr = 8) and an ester-linked diamine achieved unprecedented outstanding dielectric properties without the support of fluorinated monomers, specifically an ultra-low dissipation factor (tan δ) of 0.00128 at a frequency of 10 GHz (50% RH and 23 °C), in addition to an extremely high glass transition temperature (Tg) of 365 °C, extremely low linear coefficient of thermal expansion (CTE) of 6.8 ppm K−1, suppressed water uptake (0.24%), requisite film ductility, and a low haze. Consequently, certain PEsI films developed in this study are promising candidates for heat-resistant dielectric substrates for use in 5G-compatible high-speed flexible printed circuit boards (FPCs). The chemical and physical factors denominating tan δ are also discussed. [ABSTRACT FROM AUTHOR]

Context: The effects of selected substituent groups (-CH3, -Br, -CO2CH3, -COOH, and -NH2) and their relative positions on the electronic and structural properties of mono-substituted naphthalenes were investigated theoretically. In order to elucidate the suitability of the studied substituents in different fields including chemistry, spectroscopy, and materials sciences, accurate DFT calculations were performed at the dispersion-corrected B3LYP level of theory (B3LYP-D3/6–311 + + G(d,p)), and the obtained results were then validated by extensive comparisons with available experimental data. Among the studied substituents, the -NH2 group causes the maximum reduction of the HOMO–LUMO energy gap. This result revealed clearly the suitability of the -NH2 group, compared to other studied substituents, in the chemical synthesis of future organic-semiconductors having small energy gaps. In addition, the level of theory adopted in this study allowed the fine discrimination between the chemical reactivity parameters of the studied congeners, which is very difficult to perform experimentally. On the other hand, the rotational barriers of the studied non-halogen substituent groups were predicted. The greater sensitivity of the rotational barrier heights to the local environments, arising from intra-molecular interactions, was attributed to the -CH3 group. The torsional frequencies, calculated within the harmonic approximation, were also employed to relatively explore the differences between the environments of the same substituent at two different positions. The usefulness of these results can be manifested in the vibrational spectroscopy field, especially, for the IR/ Raman spectral analysis of polycyclic-aromatic congeners. Method: All calculations were conducted within the Density functional theory (DFT) using the so-called dispersion-corrected B3LYP functional (B3LYP-D3) with the carefully selected 6–311 + + G(d,p) basis set. The B3LYP-D3/6–311 + + G(d,p) calculations were performed using the Gaussian 09 program, and the obtained results were visualized by employing the GaussView 6.0.16 program. [ABSTRACT FROM AUTHOR]

The unusual reactivity of key enamine intermediates led to the formation of 3-methylamino-2-(2-nitrobenzoyl)-4H-naphthalen-1-one as an unexpected product in an attempted synthesis of the P. aeruginosa metabolite 2-benzyl-4(1H)-quinolone. Although the synthesis of the natural product has not been successful, this methodology allows for the easy preparation of novel derivatives carrying a carboxamide moiety at the C3 position.

A new approach for synthesizing selenylated naphthalene derivatives is described herein, employing trichloroisocyanuric acid (TCCA) as the oxidizing agent. The developed protocol yielded 18 compounds, with yields ranging from 32 % to 90 %. Additionally, the reaction was conducted under mild conditions, utilizing ethanol as the solvent at room temperature, demonstrating good atom economy. The key aspect of the protocol is the in situ generation of electrophilic selenium species through the reaction of diorganyl diselenides and TCCA. [ABSTRACT FROM AUTHOR]

Perfluorohalogenated naphthalenes (PFXNaPs) are unique small molecules with great potential to exhibit a new type of σ-hole and π-hole bonding, owing to the incorporation of multiple F atoms onto the naphthalene ring. In this study, we develop a synthetic protocol for PFXNaPs, conduct crystal engineering investigations, and explore the intermolecular interactions of PFXNaPs through π-hole and σ-hole bondings. We successfully synthesise PFXNaPs using Mg amide-mediated halogenation reactions of electron-deficient F7 and F6 naphthalenes, achieving good to excellent yields. Crystal structure analyses of 3,6-I2F6 naphthalene unveil intermolecular π-hole stacking between two C atoms in the naphthalene ring, involving cooperation with the σ-hole bonding of two I atoms. This intermolecular interaction mode has not been classified in previous reports. Computational studies show that the π-hole bonding in PFXNaPs is substantially enhanced compared to corresponding benzene molecules without diminishing the σ-hole bonding. The unique stacked interaction in PFXNaPs is primarily governed by electrostatic interaction and dispersion correction energies, with the contribution of C⋯C contacts being 10 times greater than that in benzene analogs. The results enable further applications of PFXNaPs in the fields of perfluorohalogenated arenes and organic crystalline materials. [ABSTRACT FROM AUTHOR]

Dearomative intramolecular Diels–Alder/sulfur extrusion reaction of thiophenes with alkynes successfully afforded fluoranthenes in moderate to excellent yields. The proximity of both reactive sites fixed at the peri‐position of naphthalene would play an important role in the progress of this reaction. Tri(o‐tolyl)phosphine effectively suppressed the side reactions as a sulfur scavenger. [ABSTRACT FROM AUTHOR]

This study investigates the utilisation of coal tar naphthalene oil fraction (CTNOF), an economical by-product derived from the iron-steel industry, for the production of valuable chemicals, with a particular focus on methylnaphthalenes (MNs) and dimethylnaphthalenes (DMNs). Of specific interest is 2,6-dimethylnaphthalene (2,6-DMN), a pivotal component in the manufacture of polyethylene naphthalate (PEN). The intricate and costly nature of 2,6-DMN production currently poses challenges to the commercial viability of PEN. This study provides the potential heterogeneous reaction pathways for the synthesis of MNs and DMNs via methylation, disproportionation, and isomerisation of CTNOF. The utilisation of CTNOF was investigated in a laboratory-scale fixed bed reactor operating at atmospheric pressure using a mixture of CTNOF: methanol having 1:5 mass ratio over HBeta zeolite catalyst at a temperature of 400 °C and weight hourly space velocity of 2 h−1. The results reveal the successful methylation of CTNOF over the HBeta zeolite catalyst, initially achieving high naphthalene conversion, particularly into 2-MN. This highlights the potential of CTNOF as an alternative feedstock for the production of value-added chemicals. While naphthalene conversion initially reaches 99 wt% within 0.5 h of operation, it gradually decreases to approximately 10 wt% over extended run times. Notably, coke deposition significantly deactivates the HBeta zeolite catalyst during CTNOF methylation, impacting naphthalene conversion. A substantial proportion of naphthalene compounds convert to methylnaphthalenes early in the reaction, predominantly 2-MN, increasing from 14 wt% (in CTNOF feedstock) to 87 wt%. Among DMNs, selectivity for 2,6-DMN, 2,7-DMN, 1,3-DMN, and 1,7-DMN increases, while other DMN isomers exhibit a sharp decrease in selectivity. The distribution of 2,6-triad DMNs rises from 38 wt% in feedstocks to 52–55 wt% with extended reaction times, attributed to MN conversion to DMNs and potential isomerisation from other DMNs. This study underscores the feasibility of using CTNOF for the direct synthesis of valuable chemicals, specifically 2,6-DMN and 2-MN, through methylation over HBeta zeolite catalysts. However, it emphasises the critical role of residence time in coke deposition and the need for optimisation, particularly regarding this parameter, to ensure the efficiency of this catalytic process. [ABSTRACT FROM AUTHOR]

Novel chemically modified electrodes (CMEs) based on azulene were prepared by electrooxidation of guaiazulene derivative 4-((5-isopropyl-3,8-dimethylazulen-1-yl)methylene)-2-phenyloxazol-5(4H)-one (G). G is based on guaiazulene non-alternating aromatic hydrocarbon exhibiting a less symmetrical structure compared to naphthalene skeletal derivative. Therefore, it can be used as a building block for the preparation of novel materials. To evaluate the chemical structure and surface images, the CMEs based on G (G-CMEs) were characterized by ferrocene redox probe, X-ray photon spectroscopy (XPS), and scanning electron microscopy (SEM). They were also tested for the analysis of synthetic samples of heavy metal (HM) ions. The influence of preparation conditions (electric charge and potential) on the properties of these CMEs was examined. This paper highlights the importance of electropolymerization conditions on electrodeposited film surfaces, especially on their analytical properties vs. Cd(II), Pb(II), Cu(II), and Hg(II) investigated ions. This study is relevant for further design and development of advanced materials based on azulenyl-phenyloxazolone for the HM analysis in water. A linear dependence of the peak currents for Pb(II) ion on the concentration in test aqueous solutions was obtained between 10−7 M and 5·10−5 M. The detection limits of 5·10−6 M; 10−7 M; 5·10−6 M; and 10−5 M were estimated for Cd(II), Pb(II), Cu(II), and Hg(II), respectively, for G-CMEs. [ABSTRACT FROM AUTHOR]

Objective/Background: The genus Diospyros L. (Ebenaceae) includes about 778 species worldwide, with over 500 of them known for their significant health benefits. Among them, Diospyros mollis Griff. has been used as a tonic and treatment for many diseases related to digestive disorders and intestinal parasites. Furthermore, the fruit has also been used for dyeing silk fabrics. The purpose of this comprehensive review is to provide researchers with important information about D. mollis, particularly regarding its chemical composition and biological effects. This information can support current understanding and future studies to develop novel herbal formulations based on this species. Additionally, this review aims to compile and summarize the available literature on this species, covering its botanical, ethnomedicinal, phytochemical, and pharmacological properties reported to date. Methods: The relevant information on D. mollis was collected via online electronic and databases, including Scopus, Pubmed, Web of Science, Google Scholar, ScienceDirect, Springer Link, SciFinder, and other scientific databases. Results: A comprehensive review of the literature reveals that D. mollis contains various chemical constituents such as naphthalene and naphthoquinone derivatives, triterpenoids, alkaloids, sterols, glycosides, and fatty acid esters isolated from the berry, root, bark, and leaf of this species, with several pharmacological effects and other applications. Many pharmacological effects, such as hyaluronidase inhibitory, anthelmintic, and antiparasitic activities of various extracts and isolated compounds of D. mollis, are reported in this review. The review demonstrates the importance of D. mollis in the treatment of diseases, its application in fabric dyeing techniques, and its traditional use. Conclusion: In conclusion, D. mollis emerges as a promising botanical resource with its rich history in traditional medicine and diverse chemical constituents, paving the way for potential future applications and innovations in the field of herbal medicine and drug development. [ABSTRACT FROM AUTHOR]

The fixation of carbon dioxide with epoxides is one of the most attractive methods for the green utilisation of this greenhouse gas and leads to many valuable chemicals. This process is characterised by 100% atom efficiency; however, an efficient catalyst is required to achieve satisfactory yields. Metal–organic frameworks (MOFs) are recognised as being extremely promising for this purpose. Nevertheless, many of the proposed catalysts are based on ions of rare elements or elements not entirely safe for the environment; this is notable with commercially unavailable ligands. In an effort to develop novel catalysts for CO2 fixation on an industrial scale, we propose novel MOFs, which consist of aluminium ions coordinated with commercially available 1,4-naphthalene dicarboxylic acid (Al@NDC) and their nanocomposites with gold nanoparticles entrapped inside their structure (AlAu@NDC). Due to the application of 4-amino triazole and 5-amino tetrazole as crystallization mediators, the morphology of the synthesised materials can be modified. The introduction of gold nanoparticles (AuNPs) into the structure of the synthesised Al-based MOFs causes the change in morphology from nano cuboids to nanoflakes, simultaneously decreasing their porosity. However, the homogeneity of the nanostructures in the system is preserved. All synthesised MOF materials are highly crystalline, and the simulation of PXRD patterns suggests the same tetragonal crystallographic system for all fabricated nanomaterials. The fabricated materials are proven to be highly efficient catalysts for carbon dioxide cycloaddition with a series of model epoxides: epichlorohydrin; glycidol; styrene oxide; and propylene oxide. Applying the synthesised catalysts enables the reactions to be performed under mild conditions (90 °C; 1 MPa CO2) within a short time and with high conversion and yield (90% conversion of glycidol towards glycerol carbonate with 89% product yield within 2 h). The developed nanocatalysts can be easily separated from the reaction mixture and reused several times (both conversion and yield do not change after five cycles). The excellent performance of the fabricated catalytic materials might be explained by their high microporosity (from 421 m2 g−1 to 735 m2 g−1); many catalytic centres in the structure exhibit Lewis acids' behaviour, increased capacity for CO2 adsorption, and high stability. The presence of AuNPs in the synthesised nanocatalysts (0.8% w/w) enables the reaction to be performed with a higher yield within a shorter time; this is especially important for less-active epoxides such as propylene oxide (two times higher yield was obtained using a nanocomposite, in comparison with Al-MOF without nanoparticles). [ABSTRACT FROM AUTHOR]

Despite their apparent simplicity and numerous potential applications, 1,8‐bis(boronic ester) derivatives of naphthalene, 1,8‐C10H6[B(OR)2]2, have remained elusive until today. We now disclose a facile access route to this compound class via alkoholysis of the 1,8‐naphthalenediyl‐bridged diborane(6) 1. In the cases of monotopic MeOH or EtOH, the target compounds 1,8‐C10H6[B(OR)2]2 (R=Me (2), Et (4)) are contaminated with about 10 % of the corresponding mixed boronic ester/anhydride. By using ditopic pinacol (pin) or 1,8‐naphthalenediol (ndl), the formation of the undesired side products is suppressed and 1,8‐C10H6(Bpin)2 (6) can be isolated in 80 % yield (due to solubility issues, the yield of 1,8‐C10H6(Bndl)2 (7) is lower and less reproducible). The bis(boronic ester)s 2, 4, 6, and 7 have been structurally characterized by X‐ray diffraction. 6 has a sterically encumbered, remarkably distorted molecular framework with a torsion angle B−C(ipso)−C'(ipso)−B' of 38.63(9)°. [ABSTRACT FROM AUTHOR]

We have developed a new scaffold that exhibits an efficient intramolecular through-space charge transfer (CT). In this design, electron-rich benzofuran and electron-deficient ynone groups are placed strategically in proximity via a naphthalene spacer. Charge transfer is supported by distinct CT bands in the visible region (>500 nm) in their UV-vis absorption and emission spectra. [ABSTRACT FROM AUTHOR]

Bridged benzazepine scaffolds, possessing unique structural and physicochemical activities, are widespread in various natural products and drugs. The construction of these skeletons often requires elaborate synthetic effort with low efficiency. Herein, we develop a simple and divergent approach for constructing various bridged benzazepines by a photocatalytic intermolecular dearomatization of naphthalene derivatives with readily available α‐amino acids. The bridged motif is created via a cascade sequence involving photocatalytic 1,4‐hydroaminoalkylation, alkene isomerization and cyclization. Interestingly, the diastereoselectivity can be regulated through different reaction modes in the cyclization step. Moreover, aminohydroxylation and its further bromination have also been demonstrated to access highly functionalized bridged benzazepines. Preliminary mechanistic studies have been performed to get insights into the mechanism. This method provides a divergent synthetic approach for construction of highly functionalized bridged benzazepines, which have been otherwise difficult to access. [ABSTRACT FROM AUTHOR]

We synthesized novel polyelectrolytes based on naphthalene diimide with quaternary amine featuring hydroxyl groups at the side chain, along with different counteranions (PF-NDIN-Br-OH and PF-NDIN-I-OH) for polymer solar cell (PSC) application as the interlayer. The polyelectrolytes establish a beneficial interface dipole through the ionic moieties and synergistic effects arising from the hydroxyl groups located at the side chain. Incorporating polyelectrolytes as the cathode interlayer resulted in an enhancement of the power conversion efficiency (PCE). The PCE of the device with PF-NDIN-Br-OH increased from 8.96% to 9.51% compared to the ZnO-only device. The best PCE was obtained with the device based on PF-NDIN-I-OH, up to 9.59% resulting from the J s c enhancement. This outcome implies a correlation between the performance of the device and the synergistic effects observed in polyelectrolytes containing hydroxyl groups in the side chain, along with larger anions when employed in PSCs. [ABSTRACT FROM AUTHOR]

A new naphthalene derivative, 7-acetyl-8-hydroxy-3-methoxy-6-methylnaphthalen-1-yl acetate (1), has been isolated from the stem of Rhamnus crenata, together with eight known compounds 2–9. The structure of new compound 1 was determined through spectroscopic and MS analyses. Among the isolates, emodin (3), physcion (4), quercetin 3-O-α-L-rhamnopyranoside (5), and quercetin 7-O-α-L-rhamnopyranoside (6) showed potent inhibition with IC50 values of 33.18 ± 2.73, 35.52 ± 3.27, 28.05 ± 1.85, and 26.41 ± 3.01 μM, respectively, against LPS-induced NO generation. In addition, compounds 3, 5, and 6 also showed potent DPPH radical scavenging activities with IC50 values of 95.47 ± 6.18, 68.27 ± 5.38, and 66.25 ± 4.20 μM, respectively. [ABSTRACT FROM AUTHOR]

In this study, 1,5‐dihydroxynaphthalene moiety was introduced into a novolac resin structure, and propargyl ether naphthalene phenolic resin (PNPF) was synthesized by the Williamson etherification reaction, which improved the heat resistance of the resin and its processability. The structure of the PNPF resin was characterized using 1H NMR and FTIR analysis, and its processability, heat resistance, thermal expansion, and dielectric properties were evaluated. The results revealed that the addition of 1,5‐dihydroxylhine, increased the reaction activity of the PNPF resin, and decreased its initial curing temperature, with the resin exhibiting excellent processability. The cured resin also showed excellent heat resistance and thermomechanical properties. The 5% weight loss temperature (Td5) and glass transition temperature (Tg) of the resin increased to 437.61 and 362.04°C, respectively, while the coefficient of thermal expansion decreased from 60.17 to 44.52 ppm, with a reduction of 26.01%. Moreover, the dielectric constant and dielectric loss of the cured resin were 3.02 and 0.00239, respectively. [ABSTRACT FROM AUTHOR]

The purpose of this paper is elucidating the stereochemistry of a complex obtained by coordinating to divalent nickel a naphthalene-1,4-dione based chemical compound, namely N-(3-mercapto-naphthalene-1,4-dione-2-yl)nicotinamide. As this particular transition metal ion may lead to different coordination geometries and also tacking into account the fact that the organic ligand contains six heteroatoms, it seem to be worth clarifying denticity of the ligand, the coordination geometry (including stereoisomerism) and, of course, what are the atoms involved into the coordination process. The study has been conducted by computational means, followed by quantum-chemical calculations and comparative interpretation of the UV-Vis spectra of both the ligand and the complex compound, in order to find out in which case the structural assessment is consistent with the electronic transitions exhibited whithin the spectra, i.e. which of the several theoretical coordination posibilities is the actual one. This investigation leads to the conclusion that the organic compound acts as a bidentate ligand and, moreover, the complex compound has a square-planar coordination geometry, the two heteroatoms through which the coordination is realized being the sulfur atom and the nitrogen atom directly bonded to the naphthalene-1,4-dione heterocycle. This is an important achievement, as the properties of the complex compound – including its biologic activity - are obviously related to the coordination manner. [ABSTRACT FROM AUTHOR]