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The total oxidizable precursor (TOP) assay has been extensively used for detecting PFAS pollutants that do not have analytical standards. It uses hydroxyl radicals (HO•) from the heat activation of persulfate under alkaline pH to convert H-containing precursors to perfluoroalkyl carboxylates (PFCAs) for target analysis. However, the current TOP assay oxidation method does not apply to emerging PFAS because (i) many structures do not contain C-H bonds for HO• attack and (ii) the transformation products are not necessarily PFCAs. In this study, we explored the use of classic acidic persulfate digestion, which generates sulfate radicals (SO4-•), to extend the capability of the TOP assay. We examined the oxidation of Nafion-related ether sulfonates that contain C-H or -COO-, characterized the oxidation products, and quantified the F atom balance. The SO4-• oxidation greatly expanded the scope of oxidizable precursors. The transformation was initiated by decarboxylation, followed by various spontaneous steps, such as HF elimination and ester hydrolysis. We further compared the oxidation of legacy fluorotelomers using SO4-• versus HO•. The results suggest novel product distribution patterns, depending on the functional group and oxidant dose. The general trends and strategies were also validated by analyzing a mixture of 100000- or 10000-fold diluted aqueous film-forming foam (containing various fluorotelomer surfactants and organics) and a spiked Nafion precursor. Therefore, (1) the combined use of SO4-• and HO• oxidation, (2) the expanded list of standard chemicals, and (3) further elucidation of SO4-• oxidation mechanisms will provide more critical information to probe emerging PFAS pollutants.

Laccases from white-rot fungi catalyze lignin depolymerization, a critical first step to upgrading lignin to valuable biodiesel fuels and chemicals. In this study, a wildtype laccase from the basidiomycete Fomitiporia mediterranea (Fom_lac) and a variant engineered to have a carbohydrate-binding module (Fom_CBM) were studied for their ability to catalyze cleavage of β-O-4 ether and C-C bonds in phenolic and non-phenolic lignin dimers using a nanostructure-initiator mass spectrometry-based assay. Fom_lac and Fom_CBM catalyze β-O-4 ether and C-C bond breaking, with higher activity under acidic conditions (pH < 6). The potential of Fom_lac and Fom_CBM to enhance saccharification yields from untreated and ionic liquid pretreated pine was also investigated. Adding Fom_CBM to mixtures of cellulases and hemicellulases improved sugar yields by 140% on untreated pine and 32% on cholinium lysinate pretreated pine when compared to the inclusion of Fom_lac to the same mixtures. Adding either Fom_lac or Fom_CBM to mixtures of cellulases and hemicellulases effectively accelerates enzymatic hydrolysis, demonstrating its potential applications for lignocellulose valorization. We postulate that additional increases in sugar yields for the Fom_CBM enzyme mixtures were due to Fom_CBM being brought more proximal to lignin through binding to either cellulose or lignin itself.

A single-step phenylation at the non-acidic C(sp3)–H bond attached to the heteroatom of ethers and N -Boc-amines has been achieved using photoexcited 4-benzoylpyridine as a hydrogen atom transfer (HAT) catalyst. The design of electron-deficient (trifluoromethylsulfonyl)benzene derivatives, as a phenyl precursor, was critical to realizing the present transformation. Moreover, the DFT calculations indicated that the present transformation proceeds via a concerted homolytic aromatic substitution rather than via a stepwise one involving the formation of a cyclohexadienyl radical intermediate. [ABSTRACT FROM AUTHOR]

An efficient iodide ion (I−)-enabled method for direct α-C(sp3)–H triazolization of ethers via a radical cross-coupling has been developed for regioselective construction of N2-substituted hemiaminal ethers. The developed C(sp3)–H triazolization reaction features the resulting products in good yields (up to 90%) and an excellent functional group tolerance to various ethers, including cyclic and linear ethers. Preliminary mechanistic study and DFT calculation investigation indicate that the reaction proceeds via a SN2-like desulfonylation radical coupling process and an (I−)-involved ternary complex is responsible for the high conversion ratio and the high regioselectivity. I− not only promotes the process but also prevents the in situ generated carbon-centered radicals (CCRs) from being oxidized into carbon cations in an oxidative environment. [ABSTRACT FROM AUTHOR]

Background: Chronic alcohol users often exhibit an increased minimum alveolar concentration (MAC) of sevoflurane, yet the specific mechanism remains unclear. It has been reported that ethanol exposure can upregulate the protein expression and enzyme activity of cytochrome P450 2E1 (CYP2E1). CYP2E1 is a key enzyme that converts 2–5% of sevoflurane into equimolar amounts of hexafluoroisopropanol (HFIP) and F−. This study aims to explore whether ethanol exposure could alter sevoflurane metabolism through CYP2E1 modulation, potentially explaining the increased MAC observed in alcohol users. Methods: Eighty adult male Sprague-Dawley (SD) rats were randomly divided into two groups and received either 50% ethanol (dose: 3 g/kg) or 0.9% saline twice daily by gavage. After 1, 2, 3, and 4 weeks of gavage, ten rats were randomly selected from each group to undergo 1-hour anesthesia with 2.3% sevoflurane. Blood samples were collected after anesthesia to measure the concentration of free HFIP using gas chromatography. Additionally, the left lobe tissue of the liver was collected for the analysis of CYP2E1 protein expression by Western blot and CYP2E1 enzyme activity by colorimetric assay. Correlations between these parameters were analyzed using Pearson's correlation. Results: In the ethanol group, CYP2E1 expression, activity, and the concentration of free HFIP were significantly higher at all time points compared to the control group (P < 0.05), except for protein expression in the first week (P > 0.05). Within-group comparisons indicated no significant changes in any of the parameters for the control group (P > 0.05). In the ethanol group, there was no difference in free HFIP concentration between the first and second weeks (P > 0.05), but a significant increase was observed in the third and fourth weeks (P < 0.01); protein expression and enzyme activity significantly varied over time, especially showing a notable increase from the first to the third and fourth weeks (P < 0.05). Correlation analysis revealed strong positive correlations between free HFIP concentration and CYP2E1 activity (r = 0.7898), free HFIP concentration and CYP2E1 expression (r = 0.8418), and CYP2E1 activity and expression (r = 0.8740), all with P < 0.001. Conclusions: Ethanol exposure increased both the expression and enzymatic activity of CYP2E1, consequently enhancing the metabolism of sevoflurane. [ABSTRACT FROM AUTHOR]

The alkylation of 4-hydroxythiocoumarins (1a–f) was carried out with various allyl bromides as well as propargyl bromides using K2CO3 (2 equiv.) in anhydrous acetone at room temperature, and the corresponding regioselective S-alkylated products 4a–l and 5a–n were obtained in good yields. Then, the synthesis of a variety of new sulfur heterocycles is accomplished by employing thio-Claisen rearrangement from the corresponding S-allyl ethers (4a–l) and S-propargyl ethers (5a–n) to provide the cyclised products 7a–o and 8a–n in good yields. Interestingly, the S-propargyl ethers of the corresponding 4-hydroxythiocoumarins (1a–f) provided two different products depending on the solvent. Furthermore, various 4-hydroxythiocoumarins provided the cyclised products 10a–f directly upon reaction with 2-methylbut-3-yn-2-ol (9) in the presence of 10 mol% p-TSA as catalyst in nitromethane solvent at 80 °C. DFT calculations were performed to investigate the formation of different products, and the findings have been thoroughly discussed. The results demonstrate several notable attributes, including good to excellent yield, highly regioselective product formation, and high atom economy. [ABSTRACT FROM AUTHOR]

Transition metal–catalyzed cross-couplings have great potential to furnish complex ethers; however, challenges in the C(sp3)–O functionalization step have precluded general methods. Here, we describe computationally guided transition metal–ligand design that positions a hydrogen-bond acceptor anion at the reactive site to promote functionalization. A general cross-coupling of primary, secondary, and tertiary aliphatic alcohols with terminal olefins to furnish >130 ethers is achieved. The mild conditions tolerate functionality that is prone to substitution, elimination, and epimerization and achieve site selectivity in polyol settings. Mechanistic studies support the hypothesis that the ligand’s geometry and electronics direct positioning of the phosphate anion at the p-allyl-palladium terminus, facilitating the phosphate’s hydrogen-bond acceptor role toward the alcohol. Ligand-directed counteranion positioning in cationic transition metal catalysis has the potential to be a general strategy for promoting challenging bimolecular reactivity. [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]

Novel elastomers are made by reaction of hydroxyl‐terminated polyacrylic ester (HyTemp) with polyethylene glycol (PEG, number of ethylene glycol units 1, 3, 6, 9) based cross‐linkers. The influence of the cross‐linker length, the HyTemp/cross‐linker (w/w) ratio and the cross‐linking accelerator trifluoromethanesulfonate scandium salt (ScTFMS) on the structure and the properties of the materials are studied. The cross‐linker length has not influence on the glass transition (Tg) of the products because of the presence of the flexible PEG units that cancels out the cross‐linking effect associated to a shift to higher Tg. A two‐domain structure is seen by the presence of a dual Tg in samples cured with ScTFMS. Mathematical analysis of the modulated differential scanning calorimetry curves offers for the first time the possibility to identify/confirm structural differences in complex three‐dimensional polymeric structures. Scanning electron microscopy and swelling experiments in ethyl acetate respectively reveal an increase in the pore size (1.13 to 5.48 nm) and in the absorption ability of the elastomers cured with different types and quantities of PEG cross‐linker. The new elastomeric materials are exhibiting a rubbery state over a wide temperature range and absorptivity for the potential recovery of pollutants in soil and/or water. [ABSTRACT FROM AUTHOR]

The realization of lithium‐metal (Li) batteries faces challenges due to dendritic Li deposition causing internal short‐circuit and low Coulombic efficiency. In this regard, the Li‐deposition stability largely depends on the electrolyte, which reacts with Li to form a solid electrolyte interphase (SEI) with diverse physico‐chemical properties, and dictates the interphasial kinetics. Therefore, optimizing the electrolyte for stability and performance remains pivotal. Hereof, glyme ethers are an emerging class of electrolytes, showing improved compatibility with metallic Li and enhanced stability in Li─Air and Li─Sulfur batteries. Yet, the criteria for selecting glyme solvents, particularly concerning Li deposition and dissolution processes, remain unclear. The SEI characteristics and Li deposition/dissolution processes are investigated in glyme‐ether‐based electrolytes with varying chain lengths, using lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and lithium nitrate (LiNO₃) salts under high capacity and limited electrolyte conditions. Longer glymes led to more homogeneous SEI, particularly pronounced with LiNO₃, minimizing surface roughness during stripping, and promoting compact Li deposits. Higher reductive stability, resulting in homogeneous interphasial properties, and slower kinetics due to high desolvation barrier and viscosity, underline stable Li growth in longer glymes. This study clarifies factors guiding the selection of glyme ether‐based electrolytes in Li metal batteries, offering insights for next‐generation energy storage systems. [ABSTRACT FROM AUTHOR]

We report a photochemical method for the semipinacol rearrangement of unactivated allylic alcohols. Aliphatic as well as aromatic groups participate as migrating groups, yielding a variety of α,α‐disubstituted ketones. The reaction proceeds under mild conditions and is compatible with ethers, esters, halides, nitriles, carbamates, and substituted arenes. The operationally simple and fully catalytic conditions prescribe 1 mol % benzothiazinoquinoxaline as organophotocatalyst, 0.5 mol % Co‐salen, and 10 mol % lutidinium triflate and, importantly, display reactivity complementary to procedures employing Brønsted acid. We showcase the utility of the protocol in late‐stage drug diversifications. [ABSTRACT FROM AUTHOR]

Photochemical multi-component coupling reactions initiated by the activation of glycosyl bromides in the presence of 1,4-bis(diphenylamino)benzene (BDB) as an organic photocatalyst were developed. C-glycosides accompanied by olefin (di)functionalization were obtained. This method allows us to access various C-glycosides with alkene, carbonyl, alcohol, ether, and amide functionalities. [ABSTRACT FROM AUTHOR]

Background: cultivated and wild plants are used to treat different ailments. The Astragalus genus is found in temperate and dry climates; thus, it is found in Egypt and the arab world. Astragalus caprinus has a good amount of bioactive chemicals, which may help explain its therapeutic effects in reducing the risk of consequences from disease. Method: The phytochemical investigation of the herb and roots of Astragalus caprinus L. included the analytical characterization for the petroleum ether components by GC/MS, unsaponifiable matter (unsap. fraction), and fatty acids (FAME) investigation by GLC analysis. Main flavonoids were chromatographically isolated from ethyl acetate and n-butanol extracts. In vitro antimicrobial activity has been tested against the Gram-positive bacteria Staphylococcus aureus and Streptococcus mutans for different plant extracts, the Gram-negative bacteria Pseudomonas aeruginosa and Klebsiella pneumonia, the fungus Candida albicans and Aspergillus niger, and the Escherichia coli bacterium. Metabolite cytotoxicity was examined using the MTT assay against HepG-2 (human liver carcinoma) and MCF-7 (breast carcinoma). Results: Identifying the important components of the herb and root petroleum ether extracts was achieved. Using column chromatography, luteolin, cosmosiin (apigenin-7-O-glucoside), and cynaroside (luteolin-7-O-glucoside) were separated and identified using UV, NMR, and Mass Spectroscopy. Root extracts displayed potential antimicrobial activity against most of the tested pathogens. Both extracts (herb and roots) were active against the MCF-7 cell line and HepG-2 cell line with IC50 62.5 ± 0.64 and 72.4 ± 2.3 µg/ml, and 75.9 ± 2.5 and 96.8 ± 4.2 µg/ml, respectively. Conclusion: Astragalus caprinus seems to be a promising source of bioactive compounds that could potentially aid in preventing disease complications and address common health issues in developing countries. Moreover, the various parts of this plant could be utilized as natural raw materials for producing health-boosting products that could address common health issues in developing countries. [ABSTRACT FROM AUTHOR]

Musca domestica L., a common housefly, and Culex quinquefasciatus mosquito are quite well-known pests that can transfer a wide range of diseases to humans as well as animals. In this study, various isoborneol derivatives including esters, ethers, and thioethers were synthesized from isoborneol under mild conditions. These derivatives were evaluated for inhibition of house-fly M. domestica adults and Cx. quinquefasciatus larvae. Two of the synthesized isoborneol ester derivatives (2 and 3) showed good activity against both insect species. Additional two derivatives (6 and 9) were active against M. domestica L., and the derivatives (1–3, 8) were active against Cx. quinquefasciatus larvae. [ABSTRACT FROM AUTHOR]

Aqueous zinc-ion batteries (AZIBs) have been getting lots of attention in the field of large scale energy storage owing to their low cost, large capacity and excellent safety. However, Zn anodes have serious dendritic growth and corrosion hydrogen evolution issues, which hinder their further application. Herein, a simple drop-coating technique was used to build a thin sulfate poly(ether ketone) (SPEEK) solid-electrolyte interphase (SEI) on the surface of the Zn anode to address these issues. The sulfonated group (−SO3−） in SPEEK can provide rich coordination sites for Zn2+, controlling the uniform deposition of Zn2+. Therefore, the polymer SEI can block electrolytes and homogenize the Zn2+ flux, resulting that the modified Zn (SPEEK@Zn) anode could effectively limit the formation of dendrites and side reactions. At a current density of 0.5 mA cm−2, SPEEK@Zn electrodes can maintain an ultra-long plating/stripping cycle life of 1000 h. Full batteries based on SPEEK@Zn have more superior cycle stability than the bare ones. This approach offers a straightforward and scalable remedy for high-performance Zn anode batteries. [ABSTRACT FROM AUTHOR]

A stereoselective synthesis of the C1–C13 segment of poecillastrin C has been achieved. The C1–C4 moiety was derived from diallyl l -tartrate, and the amide group at the C3 position was constructed by means of a traceless Staudinger reaction. The C1–C13 segment was submitted to model studies, including esterification with a bulky alcohol at the C1 position and Stille coupling with vinyl iodide at the C13 position. The reactivity of the C1 position was affected by the neighboring C2-protective group. When the C2 hydroxy group was protected as a TBS ether, the C1 carboxylic acid did not undergo esterification with a bulky secondary alcohol, whereas the p -methoxybenzylidene N , O -acetal afforded a 2,4-dimethyl-3-pentyl ester. Stille coupling of the C1–C13 segment with 1-iodohept-1-ene gave the southern part of the poecillastrin C macrolactam attached to simplified eastern and western parts. [ABSTRACT FROM AUTHOR]

This study aims to produce diisopropyl ether (DIPE) via isopropanol dehydration using cobalt-phosphate-supported natural zeolite catalysts. The catalytic activities of the zeolite/CoO and zeolite/Co(H2PO4)2 were compared. The asprepared catalysts were assessed using X-ray diffraction (XRD), scanning electron microscopy (SEM) with energydispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, and N2 adsorption-desorption. Surface acidity was determined using the gravimetric method with pyridine as the probe. The results of this study showed that natural zeolite was favorably impregnated by CoO and Co(H2PO4)2 species. The impregnation process affected the textural and acidic features of the catalysts. The zeolite/Co(H2PO4)2 catalyst with a loading of 8 mEq.g-1 exhibited the highest surface acidity of 1.827 mmol.g-1. This catalyst also promoted the highest catalytic activity towards isopropanol dehydration, with an isopropanol conversion of 66.19%, DIPE selectivity, and yield of 46.72% and 34.99%, respectively. The cobalt phosphate species promoted higher catalytic activity for isopropanol dehydration than the CoO species. This study demonstrated the potential of cobalt phosphate-supported natural zeolite catalysts for DIPE production with adequate performance. [ABSTRACT FROM AUTHOR]

Comblike polycarboxylate superplasticizers (PCs) have been widely used as construction and building materials by means of high fluidity and fine dispersibility via electrostatic repulsion and steric hindrance. The conventional PCs are usually synthesized by free radical polymerization, which limit to understand and even distort the structure-property relationship due to the random molecular structure and the broad polydispersity. In this work, polycarboxylate ether superplasticizers of acrylic acid (AA) and ethylene glycol monovinyl PEG (EPEG) with controlled structure were prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization. The resultant copolymers (denoted as EPCs) were characterized by FT-IR, 1H NMR and GPC spectroscopy. The effect of actual acid/ether (AA/EPEG) ratio on the adsorption capacity and dispersion ability of EPCs in cement paste were deeply investigated. These results demonstrate that the dispersibility of EPCs with controlled molecular weights and comparatively narrow polydispersity indexes (PDI=1.2–1.4) strongly depends on the acid/ether ratio. With an increase of the feed molar ratio of AA/EPEG from 4∶1 to 8∶1 , the molecular weight and their distribution of EPCs increases accordingly. In addition, the adsorption capacity and dispersion property of EPCs to cement are densely related to the molecular structure and composition and superior to that of conventional PC analogues. A possible mechanism was proposed that EPCs can act uniformly on the surface of cement particles due to the well-defined molecular structure and well-distributed molecular weight, which is different from the conventional PCs, which will offer the fundamentals of design and synthesis for polycarboxylate superplasticizers with controlled structures. [ABSTRACT FROM AUTHOR]

Coupling by metal–carbene transfer enables the formation of several different bonds at the carbenoid site, enabling prochiral Csp3 centers that are fundamental three-dimensional substructures for medicines to be forged with increased efficiency. However, strategies using bulk chemicals are rare because of the challenge of breaking two unactivated geminal bonds. Herein, we report the reactivity of ethers to form metal–carbene intermediate by cleavage of α-Csp3–H/Csp3–O bonds, which achieve selective coupling with arylmagnesium bromides and chlorosilanes. These couplings are catalysed by cyclic (alkyl)(amino)carbene-chromium complex and enable the one-step formation of 1,n-arylsilyl alcohols and α-arylated silanes. Mechanistic studies indicate that the in-situ formed low-valent Cr might react with iodobenzene to form phenyl radical species, which abstracts the α-H atom of ether in giving α-oxy radical. The latter combines with Cr by breaking α-Csp3–O bond to afford metal–carbene intermediate, which couples with aryl Grignard and chlorosilane to form two σ-bonds. Harnessing carbenoid intermediates during organic transformations is an essential strategy for catalysis but strategies using bulk chemicals are rare due to the challenge of breaking two unactivated geminal bonds. Here, the authors report the reactivity of readily available ethers to form a metal–carbene intermediate via radical-relay bond cleavage. [ABSTRACT FROM AUTHOR]

The 1,3‐difunctionalization of unactivated alkenes is an under‐explored transformation that leads to moieties that are otherwise challenging to prepare. Herein, we report a hypervalent iodine‐mediated 1,3‐difluorination of homoallylic (aryl) ethers to give unreported 1,3‐difluoro‐4‐oxy groups with moderate to excellent diastereoselectivity. The transformation proceeds through a different mode of reactivity for 1,3‐difunctionalization, in which a regioselective addition of fluoride opens a transiently formed oxonium intermediate to rearrange an alkyl chain. The optimized protocol is scalable and shown to proceed well with a variety of functional groups and substitution on the alkenyl chain, hence providing ready access to this fluorinated, conformationally controlled moiety. [ABSTRACT FROM AUTHOR]

We report a mechanistic investigation of an aromatic dithioimide (2SS) displaying puzzling yet efficient photochemistry in ether solvents. Perplexingly, 2SS dissolved in ether solvents in a sealed and degassed vial was photochemically converted to the corresponding diimide (2OO), as determined by 1H NMR following product extraction. With no external sources of oxygen in the sample, could the oxygen in 2OO be from the ether itself? To study this unprecedented proposition, we attempt to uncover the ether's involvement in this reaction. As seen by laser‐flash photolysis, 2SS appears to first react with the solvent from its singlet excited state. Following the reaction by NMR under rigorously oxygen‐ and water‐free conditions led to the identification of a photoreductive pathway that quantitatively transformed one thione into a methylene to yield 2SH2. Subsequent oxidation of 2SH2 or irradiation of 2SS under air proved that molecular oxygen was indeed necessary to observe an oxidative pathway leading to 2OO, ruling out the initially proposed involvement of an ether oxygen. An explanation of 2SS desulfurization was further revealed through the study of solvent by‐products by GC‐MS analysis. Supported by DFT calculations, a mechanism is proposed to involve a chain reaction initiated by photochemically generated ether radical. [ABSTRACT FROM AUTHOR]

Research on the chemoselective metal‐catalyzed hydrogenation of conjugated π‐systems has mostly been focussed on enones. Herein, we communicate the understudied asymmetric hydrogenation of enimines catalyzed by N,P‐iridium complexes and chemoselective toward the alkene. A number of enoxime ethers underwent hydrogenation smoothly to yield the desired products in high yield and stereopurity (up to 99 % yield, up to 99 % ee). No hydrogenation of the C=N π‐bond was observed under the applied reaction conditions (20 bar H2, rt, DCM). It was demonstrated that the chiral oxime ether could be hydrolyzed into the ketone with complete preservation of the installed stereogenity at the α‐carbon. At last, a binding mode of the substrate to the active iridium catalyst and the consequence for the stereoselective outcome was proposed. [ABSTRACT FROM AUTHOR]

A six‐cyclic crown ether‐type pillar[5]arene was synthesized, and the five ethylene oxide loops were located outside the cavity and not affected by temperature changes which was confirmed by variable‐temperature NMR experiment in DMSO‐d6 and CDCl3 and 2D 1H−1H NOESY experiment in CDCl3. The six‐cyclic pillar[5]‐crown also showed greater binding ability of host‐guest with bis(pyridinium) derivatives than conventional alkoxy pillar[5]arenes that illustrated through 1H NMR titration spectroscopic experiment in acetone‐d6/CDCl3 (1 : 1) and UV‐vis titration experiments in CHCl3 at room temperature. The five benzocrown ethers at the periphery were able to bind metal cations by 1H NMR titration spectroscopic experiment in CD2Cl2/methanol‐d4(9 : 1). [ABSTRACT FROM AUTHOR]

The lifespan of lithium (Li) metal batteries (LMBs) can be greatly improved by the formation of inorganic‐rich electrode‐electrolyte interphases (EEIs) (including solid‐electrolyte interphase on anode and cathode‐electrolyte interphase on cathode). In this work, a localized high‐concentration electrolyte containing lithium bis(fluorosulfonyl)imide (LiFSI) salt, 1,2‐dimethoxyethane (DME) solvent and 1,2‐bis(1,1,2,2‐tetrafluoroethoxy)ethane (BTFEE) diluent is optimized. BTFEE is a fluorinated ether with weakly‐solvating ability for LiFSI so it also acts as a co‐solvent in this electrolyte. It can facilitate anion decomposition at electrode surfaces and promote the formation of more inorganic‐rich EEI layers. With an optimized molar ratio of LiFSI:DME:BTFEE = 1:1.15:3, LMBs with a high loading (4 mAh cm−2) lithium nickel manganese cobalt oxide (LiNi0.8 Mn0.1 Co0.1) cathode can retain 80% capacity in 470 cycles when cycled in a voltage range of 2.8–4.4 V. The fundamental understanding on the functionality of BTFEE revealed in this work provides new perspectives on the design of practical high‐energy density battery systems. [ABSTRACT FROM AUTHOR]

Trimethyl orthoacetate (MeC(OMe)3, TMOA) is a convenient reagent for both selective and complete O-methylation of the β-OH groups of sea urchin pigments such as spinazarin, spinochromes D and E, and echinochrome A. The reactions of these compounds with TMOA make it possible to furnish preparative amounts of 6-monomethyl ethers of spinochrome D and echinochrome A, 7-monomethyl ether (namakochrome) and 6,7-dimethyl ether of spinochrome E, which are difficult to prepare by other methods, and to carry out complete O-methylation of all discussed pigments. Among the known O-methylating agents, TMOA is most suitable for the preparative syntheses of methyl ethers of polyhydroxynaphthazarins. [ABSTRACT FROM AUTHOR]

Poly-ether-ether-ketone (PEEK) and PEEK composites are outstanding candidates for biomedical applications, such as orthopedic devices, where biocompatibility and modulus match with surrounding tissue are requisite for long-term success. The mechanical properties can be optimized by incorporating fillers such as continuous and chopped carbon fibers. While much is known about the mechanical and tribological behavior of PEEK composites, there are few articles that summarize the viability of using PEEK reinforced with carbon fibers in orthopedic implants. This paper reviews biocompatibility, tribological, and mechanical studies on PEEK and their composites with carbon fibers, notably PEEK reinforced with polyacrylonitrile (PAN)-based carbon fibers and PEEK reinforced with pitch-based carbon fibers, for application in orthopedics and total joint replacements (TJRs). The main objectives of this review are two-fold. Firstly, this paper aims to assist designers in making informed decisions on the suitability of using PEEK and PEEK composites in orthopedic applications; as it is not well understood how these materials perform on the whole in orthopedics and TJRs. Secondly, this paper aims to serve as a centralized paper in which researchers can gain information on the tribological and mechanical advancements of PEEK and PEEK composites.

Non-covalent interactions are of significance in supramolecular chemistry and biochemistry, while synthetic procedures driven by these weak interactions remain challenging and rare. Inspired by the lone pair-π interaction presence in the Z-DNA structure, a light-induced regioselective sulfonation of ethers taking advantage of the lone pair-π interaction between the oxygen of ethers and sulfonyl chlorides has been disclosed. Moreover, this strategy is also applicable to the sulfonation of aniline derivatives. Features of the methods include readily accessible starting materials, high atom-economy, green and photocatalyst-free conditions and broad functional group tolerance. Mechanism studies suggest that the lone pair-π interaction plays an important role to initiate the transformation.

We disclose a benzylic C−H oxidative coupling reaction with alcohols that proceeds through a synergistic deprotonation, halogenation and substitution sequence. The combination of tert‐butoxide bases with 2‐halothiophene halogen oxidants enables the first general protocol for generating and using benzyl halides through a deprotonative pathway. In contrast to existing radical‐based methods for C−H functionalization, this process is guided by C−H acidity trends. This gives rise to new synthetic capabilities, including the ability to functionalize diverse methyl(hetero)arenes, tolerance of oxidizable and nucleophilic functional groups, precision site‐selectivity for polyalkylarenes and use of a double C−H etherification process to controllably oxidize methylarenes to benzaldehydes. [ABSTRACT FROM AUTHOR]

The C(sp3)–H difluoroalkylation for the introduction of carbonylated CF2 groups into tetrahydroisoquinolines (THIQs) and isochromans has been achieved by using electrochemical oxidation and organozinc alkylation. This one-pot process proceeded smoothly under transition-metal catalyst- and chemical oxidant-free conditions, and the desired products were obtained in good to high yields with a broad scope, except for N-Boc-THIQ. In addition, the gram-scale experiment successfully demonstrated the promising scalability. This is the first example of an electrochemical method for C(sp3)–H difluoroalkylation of amines and ethers. [ABSTRACT FROM AUTHOR]

Lithium (Li) metal batteries (LMBs) with nickel (Ni)‐rich layered oxide cathodes exhibit twice the energy density of conventional Li‐ion batteries. However, their lifespan is limited by severe side reactions caused by high electrode reactivity. Fluorinated solvent‐based electrolytes can address this challenge, but they pose environmental and biological hazards. This work reports on the molecular engineering of fluorine (F)‐free ethers to mitigate electrode surface reactivity in high‐voltage Ni‐rich LMBs. By merely extending the alkyl chains of traditional ethers, we effectively reduce the catalytic reactivity of the cathode towards the electrolyte at high voltages, which suppresses the oxidation decomposition of the electrolyte, microstructural defects and rock‐salt phase formation in the cathode, and gas release issues. The high‐voltage Ni‐rich NCM811‐Li battery delivers capacity retention of 80 % after 250 cycles with a high Coulombic efficiency of 99.85 %, even superior to that in carbonate electrolytes. Additionally, this strategy facilitates passivation of the Li anode by forming a robust solid‐electrolyte interphase, boosting the Li reversibility to 99.11 % with a cycling life of 350 cycles, which outperforms conventional F‐free ether electrolytes. Consequently, the lifespan of practical LMBs has been prolonged by over 100 % and 500 % compared to those in conventional carbonate‐ and ether‐based electrolytes, respectively. [ABSTRACT FROM AUTHOR]

Silyl ethers fulfil a fundamental role in synthetic organic chemistry as protecting groups and their selective cleavage is an important factor in their application. We present here for the first time two enzymes, SilE−R and SilE−S, which are able to hydrolyse silyl ethers. They belong to the stress‐response dimeric A/B barrel domain (DABB) family and are able to cleave the Si−O bond with opposite enantiopreference. Silyl ethers containing aromatic, cyclic or aliphatic alcohols and, depending on the alcohol moiety, silyl functions as large as TBDMS are accepted. The X‐ray crystal structure of SilE−R, determined to a resolution of 1.98 Å, in combination with mutational studies, revealed an active site featuring two histidine residues, H8 and H79, which likely act synergistically as nucleophile and Brønsted base in the hydrolytic mechanism, which has not previously been described for enzymes. Although the natural function of SilE−R and SilE−S is unknown, we propose that these 'silyl etherases' may have significant potential for synthetic applications. [ABSTRACT FROM AUTHOR]

In this work, semi‐aromatic polyamide containing ether bond (PAE10T) was synthesized through nucleophilic substitution reaction using 1, 10‐N, N′‐bis(4‐fuorobenzamide) decane (BFBD) and hydroquinone (HQ) as the raw materials. And then the composites hydroxyapatite/semi‐aromatic polyamide (40%HA‐PAE10T and 60%HA‐PAE10T) were prepared by chemical precipitation method. Mechanical, SEM, FT‐IR, XRD, DSC, TGA and bioactivity tests were performed to characterize the structure, morphology, thermal and mechanical properties of PAE10T and its composites. Mechanical tests revealed that the difference of HA in weight played an important role in mechanical performance of the composites. Furthermore, in comparison with PAE10T, the 60%HA‐PAE10T showed the highest enhancement in compressive strength (133 MPa) at 75.9%, and the 40%HA‐PAE10T given expression to the best increase in bending strengths (97 MPa) at about 18.4%. The 40%HA‐PAE10T and 60% HA‐PAE10T exhibited the mechanical performances closed to the cortical bone of human. After 28 days of dip in the phosphate buffer saline (PBS), PAE10T, and its composites showed satisfactory stability. The cell culture results showed all composites gad good cytocompatibility, cells attached on the materials well with excellent morphology. All the experimental results showed that the composites were expected to have a good application in the field of compact bone repair. [ABSTRACT FROM AUTHOR]

The interactions between ether naphthotube and a series of dication guests in organic solution were investigated. It was found that ether naphthotube formed stable host‐guest complexes selectively with these guests in a 1 : 1 stoichiometric ratio with association constants ranging from 102 to 106 M−1, which were confirmed by 1H‐NMR spectra and ITC experiments. The host‐guest interactions are driven by enthalpy change as the entropic factors are unfavorable. Positive correlations between ΔH and ΔS have been observed in the host‐guest complexes. Furthermore, the para‐substitution of the guests can significantly affect the binding affinities through a combination of field/inductive and resonance effects by following a linear free energy relationship. Based on the host‐guest complexes composed of ether naphthotube and organic cations, two interlocked [2]rotaxanes were prepared by cationization reaction and Huisgen cycloaddition between the cations and the stopper components. The ether naphthotube‐based host‐guest complexes are useful for creating sophisticated interlocked molecules. [ABSTRACT FROM AUTHOR]

A tandem palladium-catalyzed Sonogashira coupling, propargyl-allenyl isomerization, and [2+2] cycloaddition sequence between electrondeficient haloarenes and 1,8-diynylic ethers is developed. The reaction shows good functional tolerance and proceeds under mild conditions to provide a new profile of benzooxepane-fused cyclobutene derivatives in moderate to high yields with high selectivity. The reaction mechanism is validated both by experimental studies and DFT calculations. [ABSTRACT FROM AUTHOR]

Traditional Chinese medicine (TCM) has been considered, for many years, an important source of medicine to treat different diseases. As a type of TCM, Illicium simonsii Maxim (ISM) is used as an anti-inflammatory, anti-bacterial, and anti-virus. Besides, ISM is also used in the treatment of cancer. In order to evaluate the anti-hepatocellular carcinoma (HCC) activity, petroleum ether extract was prepared from part of the fruit of ISM. First, the compounds of the petroleum ether fraction of Illicium simonsii Maxim (PEIM) were identified using LC-MS/MS analysis. Next, the cell viability and morphological changes were evaluated by MTT assay and Hoechst staining. In addition, the effect of PEIM on the levels of inflammatory factors (TNF-α, IL-1β, and IL-6) was determined using the ELISA kit. Furthermore, apoptosis was evaluated by flow cytometry, and gene expression and the regulation of signaling pathways were investigated, respectively, by real-time fluorescence quantitative PCR (RT-qPCR) and western blot. Results showed that a total of 64 compounds were identified in the PEIM. Additionally, the PEIM had anti-HCC activity against HepG2 cells, in which the half maximal inhibitory concentration (IC50) was 55.03 μg·mL−1. As well, the PEIM was able to modulate the expression of TNF-α, IL-1β, and IL-6, while we also found that it induced HepG2 cell apoptosis through the activation of P53 mRNA and caspase-3 mRNA. Finally, the PEIM possibly downregulated the expression of TLR4, MyD88, p-NF-κBp65, TNF-α, IL-1β, INOS, IL-6, JAK2, STAT3, CyclinD1, CDK4, MDM2, and Bcl-2, and upregulated the expression of P53, P21, Bax, Cytochrome-C, Caspase-9, and Caspase-3 in HepG2 cells. These findings may confirm that the PEIM has possible anti-HCC effects. However, additional studies are required to fully understand the mechanisms of action of the PEIM and the signaling pathways involved in its effects. Moreover, the anti-HCC activity of the PEIM should be studied in vivo, and signaling pathways involved in its effects should be explored to develop the anti-HCC drug. [ABSTRACT FROM AUTHOR]

The aim of the work is to develop two functionalized castor oil-based polyglycidyl ethers containing benzene rings by ring-opening etherification and alkylation reaction, respectively: phenoxy castor oil-based polyglycidyl ether (POCOGE) and phenolic castor oil-based polyglycidyl ether (PCOGE). Castor oil-based polyglycidyl ethers were introduced into E-51, which is a common type of bisphenol A epoxy resin. The thermomechanical performances of the polymer blends were evaluated. The addition of the synthetic castor oil-based polyglycidyl ethers showed an enhancement of E-51 in both toughness and flexibility without sacrificing bending strength. The tensile strength reached 81.0 MPa and 86.4 MPa, which were 26.5% and 34.9% higher compared to that of pure E-51. Meanwhile, the impact strength reached 28.1 kJ m−2 and 19.4 kJ m−2, an increase of 147% and 70.3%, respectively, compared with E-51. Scanning Electron Microscope (SEM) graphics exhibited those cured polymers had ductile fracture. The non-isothermal curing kinetics of different curing systems were analyzed by Málek's method and conformed to the Šesták–Berggren SB(m,n) model. This study aims to address the inadequate stiffness of bio-based epoxy resins and extend the scope of bio-based epoxy resins with versatile functionality. [ABSTRACT FROM AUTHOR]

The hydroxypropyl chitosan (HPCH) and hydroxyethyl chitosan (HECH) are multifunctional chitosan derivatives with biocompatible and biodegradable properties. Due to their hydroxypropyl and hydroxethyl groups, they have water solubility, moisture retention, and gelling properties. In this study, the chitosan derivatives HPCH and HECH were obtained in two steps alkalisation and etherification. For alkalisation, chitosan was kept in an alkaline medium at -18C for 7 days. For etherification; the reaction was carried out for 48 hours by mixing alkaline chitosan with propylene oxide and ethylene oxide separately in a pressure reactor. The structures of the obtained HPCH and HECH were characterised by FT-IR, 1H(13C)-NMR, XRD, and TG analysis methods. Since the degree of deacetylation (DA) of chitosan is 75-85%, the chitosan units contain N-acetyl (-N-(CO)-CH3)) groups in addition to NH2 functional groups. When the 1H(13C)-NMR spectrum of chitosan was examined, the peak value of these acetyl groups was observed at δ1.89 ppm. When the XRD spectra were examined, it was observed that the strong peak in chitosan at 2θ-20° was weakened in HPCH and HECH. In addition, the thermal stability of HPCH and HECH was found to be higher than chitosan in TG analysis. [ABSTRACT FROM AUTHOR]

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

Solvent-borne polyurethane (PU) is the main product in PU synthetic leather, which has soft handling, breathability, and moisture permeability properties by wet type. The PU film would produce the irregular foam cell by solvent exchanging water. This traditional process would use a lot of dimethylformamide, and it causes much pollution of the environment. Therefore, the water-borne polyurethane system is essential in the textile industry. This study adopted the patented prepolymer process for solvent-free water-borne polyurethane (SFWPU); the foam was formed by a blowing agent and then, coated on the polyester textile with SFWPU foam by coating machine. This research focuses on the polyol composition equivalent ratio of poly(1,4-butylene adipate) glycol (PBA) and poly(tetramethylene ether) glycol from 30:70, 20:80, 10:90, and 0:100. The crystallinity increased on the foam properties with increasing the PBA composition, affecting the foam and tensile properties. Moreover, this research finds that higher crystallinity polyol of PBA contents increased, modulus of SFWPU is increased, and tensile strength is decreased. The scanning electron microscope finds the foam cell would expand by increasing PBA contents, which affects the textile's air permeability and water vapor transmission. The 10% PBA equivalent of ester–ether type SFWPU foam coated on textile, which has windproof and keeps the moisture permeability. [ABSTRACT FROM AUTHOR]

Application of molecular electron density theory (MEDT) to investigate the [5+2] cycloaddition reaction between oxidopyrylium and ethervinylether, we discovered that oxidopyrylium is an electrophile and ethervinylether is a nucleophile by an examination of conceptual DFT indices. Analysis of energetical parameters shows clearly that this cycloaddition is both regio- and stereoselective, which is extremely consistent with the experience. Topological analysis of the electron localization function (ELF) has shown that this [5+2] cycloaddition is achieved by a two-step, single-step mechanism along the most favored route. Aside from that, docking outcomes show that the (1–20) oxabicyclo[3.2.1]octene derivatives have a significant anti-HIV potential. [ABSTRACT FROM AUTHOR]

The chemistry of extremely bulky amide ligands is troubled by difficulties in deprotonation of the parent amine. As an alternative route to superbulky amide reagents, the addition of polar reagents to a sila–imine has been investigated. Attempts to synthesize the superbulky amide anion (tBu3Si)2N− by addition of tBuLi to tBu2Si=N(SitBu3) failed and gave tBu3Si(tBu2HSi)NLi and isobutene. Reaction of the sila–imine with KOtBu successfully led to tBu3Si[tBu2(tBuO)Si]NK which crystallized as a separated ion–pair. Reaction with the slightly bulkier KOAd (Ad=1‐adamantyl) led in presence of THF to ether ring–opening. Reaction with tBuOH gave tBu3Si[tBu2(tBuO)Si]NH but this amine cannot be easily deprotonated. Reaction with (BDI*)MgnBu in presence of THF gave (BDI*)Mg+ ⋅ (THF)2 and the non–coordinating anion tBu3Si[tBu2(nBu)Si]N−; BDI*=ß‐diketiminate ligand HC[C(tBu)N−DIPP]2, DIPP=2,6‐diisopropylphenyl. Reaction of Mg(nBu)2 with tBu2Si=N(SitBu3) led to a Mg complex with one amide ligand: tBu3Si[tBu2(nBu)Si]N−. The other superbulky amide anion isomerized by internal deprotonation of a tBu‐substituent to give a primary carbanion that is also coordinated to Mg. Although the amide–to–carbanion isomerization is highly contrathermodynamic, it allows for coordination of both anions to a single Mg center. The new bulky amides are rare cases of halogen–free weakly coordinating anions. [ABSTRACT FROM AUTHOR]

A method for synthesizing silyl arylsulfonyl hydrazones as silyldiazomethane precursors has been developed. Although silyldiazomethanes are an important class of diazo compounds, their use in intramolecular cyclization reactions has not been fully explored despite the rich chemistry of diazo compounds, particularly metal carbenoid chemistry. The fundamental challenge underlying the absence of such studies is the lack of a method for synthesizing silyldiazomethanes with functional groups that can react with metal carbenoids. The method reported here provides access to variety of silyl arylsulfonyl hydrazones with functional groups such as ethers, carbamates, and alkynes, which can serve as reaction sites for metal carbenoids. A one‐pot hydrazone formation using unstable formylsilane formed in situ is key to a successful synthesis. The use of 2,4,6‐trimethylbenzenesulfonohydrazide contributed toward achieving broad generality in hydrazone formation. The synthetic potential of this method was demonstrated through the generation of silyldiazomethane and its transformation to several silacycles. [ABSTRACT FROM AUTHOR]

Herein we report the discovery and development of the first example of a cationic [1,5]‐aryl migration reaction, through an unprecedented phenonium ions. This reaction does not require any acid, base, transition metal‐based catalyst or promoter, instead promoted by the water activated NXS reagents. It provides a highly diastereoselective and rapid access to the medicinally and biologically important tetra‐substituted olefins (allyl alcohols). The involvement of an ipso‐carbon, as well as the phenonium ion during this novel, cationic [1,5]‐aryl migration was strongly supported by the isolation of 2‐oxaspiro[5.5]undecane‐9‐ones. This methodology is highly tolerable for a wide range of propargyl‐benzyl ethers, resulting in a selective construction of structurally divergent library of mono‐halo‐tricarbon‐substituted alkenes. Synthetic application has also been demonstrated by converting two isomeric‐iodo‐olefins to respective E‐ and Z‐isomers of tamoxifen in a stereospecific manner. [ABSTRACT FROM AUTHOR]

A base‐and‐additive‐free photo‐induced radical‐mediated cascade cyclization reaction of 1,6‐enyne compounds was presented. In this study, C(sp3)−H hydrocarbons, including various alkanes and ethers, were activated via Fe‐catalyzed photo‐induced conditions, providing a bunch of γ‐lactam products via hydrogen atom transfer and radical addition processes. Control experiments indicated that the reaction proceeded through photo‐induced ligand‐to‐metal charge transfer (LMCT) process. Gram scale experiment was also completed by using continuous‐flow‐photocatalytic‐device. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis of alkyl aryl ethers using diaryliodonium salts. Alkyl aryl ethers are commonly found in pharmaceuticals, agrochemicals, and functional materials. The authors propose a new method using main-group mediators to overcome the limitations of current synthetic strategies. They conducted experiments to identify the scope and limitations of the reaction and discuss the mechanistic implications of their findings, including the potential formation of arynes and the oxidation of alcohols. The article also explores the development of a method for O-arylation of aliphatic alcohols using aryl(TMP)iodonium salts, which is compatible with various types of alcohols and aryl groups. The authors conducted experiments to understand the mechanisms involved and ruled out certain background reactions. They observed the formation of aryne intermediates in some reactions but concluded that arynes are unlikely to mediate the oxidation of benzyl alcohol under the given conditions. [Extracted from the article]

The hydrogenolysis of oxygenates such as alcohols and ethers is central to the biomass valorization and also a valuable transformation in organic synthesis. However, a mild and efficient catalyst system for the hydrogenolysis of a large variety of alcohols and ethers with various functional groups is still underdeveloped. Here, we report an aluminum metaphosphate‐supported Pt nanoparticles (Pt/Al(PO3)3) for the hydrogenolysis of a wide variety of primary, secondary, and tertiary alkyl and benzylic alcohols, and dialkyl, aryl alkyl, and diaryl ethers, including biomass‐derived furanic compounds, under mild conditions (0.1–1 atm of H2, as low as 70 °C). Mechanistic studies suggested that H2 induces formation of the surface Brønsted acid sites via its cleavage by supported Pt nanoparticles. Accordingly, the high efficiency and the wide applicability of the catalyst system are attributed to the activation and cleavage of C−O bonds by the hydrogen‐induced Brønsted acid sites with the assistance of Lewis acidic Al sites on the catalyst surface. The high efficiency of the catalyst implies its potential application in energy‐efficient biomass valorization or fine chemical synthesis. [ABSTRACT FROM AUTHOR]

In this study, three excellent yellow emissive Cu(I) complexes were synthesized, namely [Cu2I2(bipy)(POP)2]·4CH2Cl2 (1), [Cu2Br2(bipy)(POP)2]·4CH2Cl2 (2), and [CuCl(bipy)(POP)]·CH2Cl2·CH3OH (3) [bipy = 4,4′-bipyridine, POP = bis(2-diphenylphosphino-phenyl)ether]. The synthesis and characterization of three complexes are introduced. Complexes 1–3 have luminescent emission peaks of 529–532 nm, belonging to yellow light emission, and their quantum yield is 72–88%. Complex 2 exhibits an exceptionally high quantum yield of 88% and its lifetime is 9.6 μs. Among the available data, this result is one of the best luminescence results for yellow luminescent cuprous complexes. This study enriches the understanding of the photophysical properties of Cu(I) complexes and offers new insights for the development of efficient OLED materials. [ABSTRACT FROM AUTHOR]

Three new heteroleptic Ag(I) complexes, labeled as [AgL(POP)]BF4 (1–3), were successfully synthesized and comprehensively characterized. Here, L represents 2,9-bis((E)-4-methoxystyryl)-1,10-phenanthroline (L1), 2,9-bis((E)-4-methylthiostyryl) -1,10-phenanthroline (L2), and 2,9-bis((E)-4-diethylaminostyryl)-1,10-phenanthroline (L3), while POP stands for Bis[(2-diphenylphosphino)phenyl] ether. The stability of these compounds in solution was confirmed through multinuclear 1D (1H, 13C, 31P) and 2D NMR (COSY, NOESY, HMBC, HSQC) spectroscopies. Additionally, their molecular structure was elucidated via X-ray crystallography. The photophysical properties of the complexes were assessed both in the solid state and in solution (dichloromethane). Compounds 1–3 demonstrated moderate emissions in solution, with quantum yields ranging from 11–23%. Interestingly, their solid-state luminescent behavior differed. Large bathochromic shifts (42–75 nm) of the emission maxima and a decrease in quantum yields (2.5–9.5%) were evident, possibly due to the presence of excimers. Compound 3 stands out as a rare example of an Ag(I) red-color emitter. [ABSTRACT FROM AUTHOR]

Biopolymers are biodegradable and renewable and can significantly reduce environmental impacts. For this reason, biocomposites based on a plasticized starch and cross-linker matrix and with a microfibrillated OCC cardboard cellulose reinforcement were developed. Biocomposites were prepared by suspension casting with varied amounts of microfibrillated cellulose: 0, 4, 8, and 12 wt%. Polyethylene glycol diglycidyl ether (PEGDE) was used as a cross-linking, water-soluble, and non-toxic agent. Microfibrillated cellulose (MFC) from OCC cardboard showed appropriate properties and potential for good performance as a reinforcement. In general, microfiber incorporation and matrix cross-linking increased crystallization, reduced water adsorption, and improved the physical and tensile properties of the plasticized starch. Biocomposites cross-linked with PEGDE and reinforced with 12 wt% MFC showed the best properties. The chemical and structural changes induced by the cross-linking of starch chains and MFC reinforcement were confirmed by FTIR, NMR, and XRD. Biodegradation higher than 80% was achieved for most biocomposites in 15 days of laboratory compost. [ABSTRACT FROM AUTHOR]

Molecules containing ether skeletons are widely present in drugs, natural products, functional materials, and life science. Direct C(sp3)−H bond ether functionalization is considered a powerful strategy for the construction of novel ether derivatives. Photo‐/electro‐chemical technology is a relatively green and sustainable synthesis method, which opens up a broad application prospect in the field of direct functionalization of C(sp3)−H bonds. In recent years, photo‐/electro‐mediated C(sp3)−H bond alkylation, arylation, alkynylation, esterification, mercaptoylation, sulfidation, and amination of ethers have been extensively studied. In this review, the research progress of photo‐/electro‐mediated C(sp3)−H bond functionalization of ether compounds from 2014 to 2023 is systematically reviewed, and the scope, limitations, and mechanisms for some reactions are discussed. [ABSTRACT FROM AUTHOR]