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Using organic dyes as photocatalysts is an innovative approach to photocatalytic organic transformations. These dyes offer advantages such as widespread availability, adaptable absorption properties, and diverse chemical structures. Recent progress has led to the development of organic photocatalysts that can utilize visible light to modify chemically inert C−H bonds. These catalysts are sustainable, selective, and versatile, enabling mild reactions, late‐stage functionalization, and various transformations in line with green chemistry principles. As catalysts in photoredox chemistry, they contribute to the development of efficient and environmentally friendly synthetic pathways. Acridinium‐based organic photocatalysts have proved valuable in late‐stage C−H functionalization, enabling transformative reactions under mild conditions. This review emphasizes their innovative features, such as organic frameworks, efficient light absorption properties, and their applications in modifying complex molecules. It provides an overview of recent advancements in the use of acridinium‐based organic photocatalysts for late‐stage C−H bond functionalization without the need for transition metals, showcasing their potential to expedite the development of new molecules and igniting excitement about the prospects of this research in the field. [ABSTRACT FROM AUTHOR]

The majority of reaction conditions employed in SF6 conversion research are characterized by elevated temperatures and pressures, resulting in a considerable expenditure of energy. The transformation of SF6 under mild conditions represents a viable methodology at this time. It has been demonstrated that the conditions required for the photoconversion of SF6 are relatively mild. Furthermore, the defect engineering of catalysts has been shown to be an effective strategy for enhancing the photocatalytic performance of photocatalysis. Thus, we utilized two-dimensional materials as a model for our research. These materials have active sites that are highly dense and uniform, allowing us to thoroughly examine how defects affect the SF6 photoconversion process. By synthesizing ZnO atomic layers with oxygen vacancies and confirming their presence using various techniques, we found that these vacancies enhanced light absorption and promoted the separation of charge carriers. These results suggest that the oxygen-deficient ZnO atomic layers have superior SF6 photoconversion performance compared to the pristine ZnO atomic layers. Overall, the findings of this study indicate that the incorporation of defects in photocatalysts is a crucial strategy for optimizing pivotal photocatalytic processes and enhancing the efficacy of SF6 photoconversion. We initially built clear models of two-dimensional atomic layers with defect concentrations, and hence directly disclose the defect type and distribution at atomic level. As a prototype, defective ZnO nanosheets with atomic thickness are successfully synthesized. Also, we use defective ZnO atomic layers to achieve light conversion of SF6 under mild conditions, which provides a new path to solve the environmental pollution of perfluorinated compounds. [ABSTRACT FROM AUTHOR]

Iron‐based catalysts play an important role in the ammonia industry. As one of the most abundant iron minerals, Fe3O4 containing FeII and FeIII sites is widely distributed in the earth's crust and even on exoplanets, theoretically giving it both economic and catalytic potentials in ammonia synthesis. However, in the absence of specific active co‐catalyst and harsh conditions, Fe3O4 is impossible to achieve ammonia synthesis alone. Here, we designed to activate the relatively inert FeII and FeIII sites in Fe3O4 with a third FeIII site inlayed in a coordination framework (MIL‐101(Fe)) to achieve the unpresented multi‐site collaborative catalysis. In‐depth mechanism study confirmed the roles of three different Fe sites in N2 activation, H2 activation, and product transfer, respectively. Efficient N2−H2 activation to NH3 on the Fe3O4‐based catalytic system has been achieved at extremely mild conditions. Our research provides a theoretical basis and a new strategy for designing efficient non‐noble metal‐based ammonia synthesis catalyst with minimized energy consumption. [ABSTRACT FROM AUTHOR]

Incorporation of CO into substrates to construct high‐value carbonyl compounds is an intensive industrial carbonylation procedure, however, high toxicity and wide explosion limits (12.5–74.0 vol% in air) of CO limit its application in industrial production. The development of a CO‐free catalytic system for carbonylation is one of ideal methods, but full of challenge. Herein, this study reports the CO‐free aminocarbonylation conversion of terminal alkynes synergistically catalyzed by a unique Co(ІІ)/Ag(І) metal–organic framework (MOF), in which the combination of isocyanides and O2 is employed as safe and green source of aminocarbonyl. This reaction has broad substrate applicability in terminal alkyne and isocyanides components with 100% atom economy. The bimetal MOF catalyst can be recycled at least five times without substantial loss of catalytic activities. Mechanistic investigations demonstrate that the synergistic effect between Ag(I) and Co(II) sites can efficiently activate terminal alkyne and isocyanides, respectively. Free radical capture experiments, FT‐IR analysis and theoretical explorations further reveal that terminal alkynes and isocyanides can be catalytically transformed into an anionic intermediate through heterolysis pathways. This work provides secure and practical access to carbonylation as well as a new approach to aminocarbonylation of terminal alkynes. [ABSTRACT FROM AUTHOR]

Among hydrogen storage chemicals for proton exchange membrane fuel cells (PEMFCs), sodium borohydride stands out for yielding exceptionally pure hydrogen. This study synthesized cobalt-molybdenum catalysts supported on g-C 3 N 4 using an ultrasonic-assisted impregnation method. Various CoMo/g-C 3 N 4 catalysts with different CoMo mass ratios were created, all showing high hydrogen production and complete NaBH 4 conversion under mild conditions. Catalytic activity depends on the cobalt-molybdenum mass ratio, with optimal performance at a 1:1 ratio (w/w), maintaining up to 83% activity over 5 cycles. The effect of operating conditions on hydrogen release was explored, resulting in the rate law: rH 2 = 1.708 × 10-3 [NaBH 4 ]1.25 [Catalyst dosage]1.39 [NaOH]0.44 at 298 K, with a low activation energy of 22.9 kJ mol−1. Molybdenum's promoting effect prevented significant deactivation of the cobalt catalyst, ensuring complete NaBH 4 conversion to H 2 and good stability over multiple cycles. [Display omitted] • CoMo/g-C 3 N 4 synthesized cost-effectively via ultrasonic-assisted impregnation. • 1:1 CoMo/g-C 3 N 4 exhibited high HGR and complete NaBH 4 conversion at mild conditions. • NaBH 4 hydrolysis using CoMo/g-C 3 N 4 presented low energy activation (22.9 kJ mol−1). • 1:1 CoMo/g-C 3 N 4 maintains selectivity for 8 cycles and 83% of activity for 5 cycles. • Molybdenum identified as a promoter reduces cobalt catalyst deactivation. [ABSTRACT FROM AUTHOR]

Four novel Pd (II), Cu (II), VO (II), and Ag(I) complexes were prepared from benzimidazole ligand through bidentate chelating mode. Alternative spectral and analytical tools were applied to elucidate their structural and molecular formulae. This study was extended to investigate stability and stoichiometry of complexes in solution, using standard methods. In addition, the best atomic distribution within structural forms was obtained via the density functional theory (DFT) method. This computational study fed us with significant physical characteristics for differentiation. Also, DFT/time‐dependent DFT computations were performed applying (B3LYP/6‐311++G[d,p]/aug‐cc‐pVTZ/aug‐cc‐pVTZ‐PP) level in order to investigate the electronic behavior of the compounds. These results demonstrated good agreement with the experimental data. Computational data discriminate Pd (II) complex by some physical features, which may be promising in the catalytic field. This complex was selected to play a catalytic function to synthesize 3‐methyl‐4‐phenyl‐4,9‐dihydro‐1H‐pyrazolo[3,4‐d][1,2,4]triazolo[1,5‐a]pyrimidine derivatives using microwave irradiation in a one‐pot reaction. The catalyst was selected for this application based on the history of Pd (II) complexes and the properties expected theoretically. A condensation reaction for 3‐methyl‐5‐pyrazolone, aromatic aldehyde, and 5‐aminotetrazole was carried out under mild reaction conditions by microwave irradiation. All reaction conditions were optimized among those variable Lewis acid catalysts in comparison with our new complexes. DOBPAPd catalyst displayed superiority in overall trials with high yield, short time, and green conditions (solvent H2O/EtOH). Also, the recovery of hetero catalyst was succeeded and reused by the same efficiency up to five times after that the efficiency was reduced. The mechanism of action was proposed based on the ability of Pd (II) for adding extra‐bonds over z‐axis and supported by theoretical aspects. [ABSTRACT FROM AUTHOR]

Abstract Incorporation of CO into substrates to construct high‐value carbonyl compounds is an intensive industrial carbonylation procedure, however, high toxicity and wide explosion limits (12.5–74.0 vol% in air) of CO limit its application in industrial production. The development of a CO‐free catalytic system for carbonylation is one of ideal methods, but full of challenge. Herein, this study reports the CO‐free aminocarbonylation conversion of terminal alkynes synergistically catalyzed by a unique Co(ІІ)/Ag(І) metal–organic framework (MOF), in which the combination of isocyanides and O2 is employed as safe and green source of aminocarbonyl. This reaction has broad substrate applicability in terminal alkyne and isocyanides components with 100% atom economy. The bimetal MOF catalyst can be recycled at least five times without substantial loss of catalytic activities. Mechanistic investigations demonstrate that the synergistic effect between Ag(I) and Co(II) sites can efficiently activate terminal alkyne and isocyanides, respectively. Free radical capture experiments, FT‐IR analysis and theoretical explorations further reveal that terminal alkynes and isocyanides can be catalytically transformed into an anionic intermediate through heterolysis pathways. This work provides secure and practical access to carbonylation as well as a new approach to aminocarbonylation of terminal alkynes.

This article proposes a milder approach for C(sp2=−H functionalization of 2,2‐disubstituted cyclopentene‐1,3‐dione via formal 1° amination utilizing water as a solvent. In addition, this approach also offers C(sp2)−O, C(sp2)−I bond formation for the first time using sodium azide. The said highly scalable transformation does not require any prefunctionalization of the starting material. Moreover, this methodology is metal free, requires no ligand and all these reactions are carried out in an open‐air atmosphere with broad substrate scope. We have also explored a novel BF3.OEt2 mediated dehalogenation using mild reaction conditions. [ABSTRACT FROM AUTHOR]

A Pd‐catalyzed formal [3+2] oxidative annulation of N‐aryl‐2‐aminopyridines and alkynes through pyridyl group directed C−H activation has been developed. This methodology provides a mild and atom‐economic approach for the efficient synthesis of highly substituted indoles in moderate to good yields, which features with mild reaction conditions, good functional group compatibility, operational simplicity and easy scale‐up. [ABSTRACT FROM AUTHOR]

A visible-light-promoted formal [2 + 2 + 1] cyclization of N-aryl glycines with quinoxalin-2(1H)-ones to synthesize tetrahydroimidazo[1,5-a]quinoxalin-4(5H)-ones have been developed. The protocol features operational simplicity, mild reaction conditions with blue LED light employing Ru(bpy)3Cl2. 6H2O as a photoredox catalyst, a combination of O2 from air and Cu(OAc)2 as the oxidant and broad substrate applicability. [ABSTRACT FROM AUTHOR]

The growing interest in green ammonia production has spurred the development of new catalysts with the potential to carry out the Haber–Bosch process under mild pressure and temperature conditions. While there is a wide experimental background on new catalysts involving transition metals, supports and additives, the fundamentals behind ammonia synthesis performance on these catalysts remained partially unsolved. Here, we review the most important works developed to date and analyze the traditional catalysts for ammonia synthesis, as well as the influence of the electron transfer properties of the so-called 3rd-generation catalysts. Finally, the importance of metal–support interactions is highlighted as an effective pathway for the design of new materials with potential to carry out ammonia synthesis at low temperatures and pressures. [ABSTRACT FROM AUTHOR]

Photocatalytic methane conversion to high value-added chemicals under mild conditions acts as a promising approach to utilize natural gas and renewable energy. Specifically, aerobic photocatalytic methane conversion that uses molecular oxygen as oxidant has attracted much attention because it is thermodynamic favorable and could generate various reactive oxygen species, resulting in many value-added products like methanol, formaldehyde, ethane, and ethylene. In this review, we classify the aerobic photocatalytic methane conversion into aerobic photocatalytic partial oxidation of methane (APPOM) and aerobic photocatalytic coupling of methane (APCM). We particularly focus on the fundamentals of oxygen activation and methane reaction modes in these conversions. Finally, we provide a brief summary for current challenges and future prospects towards aerobic photocatalytic methane conversion. [ABSTRACT FROM AUTHOR]

Methyl (3-Chloro-5-bromophenyl)carbamate (3n) Compound B 3n b was obtained from the reaction of 3-chloro-5-bromoaniline (62.0 mg, 0.3 mmol) and carbazate B 2a b (1.5 mmol, 3.0 equiv), and purified by column chromatography (10:1 PE/EtOAc). Methyl (3-Chloro-5-methylphenyl)carbamate (3o) Compound B 3o b was obtained from the reaction of 3-chloro-5-methylaniline (42.3 mg, 0.3 mmol) and carbazate B 2a b (1.5 mmol, 3.0 equiv), and purified by column chromatography (10:1 PE/EtOAc). Methyl (4-Methoxyphenyl)carbamate (3h) 29 Compound B 3h b was obtained from the reaction of 4-methoxyaniline (36.9 mg, 0.3 mmol) and carbazate B 2a b (1.5 mmol, 3.0 equiv), and purified by column chromatography (5:1 PE/EtOAc). Keywords: metal-free C-N coupling; one-pot synthesis; mild conditions EN metal-free C-N coupling one-pot synthesis mild conditions 3113 3120 8 09/11/23 20231004 NES 231004 Graph Carbamates are widely utilized as substrates in a variety of drugs and organic syntheses. [Extracted from the article]

Green and atom-economic depolymerization of lignin remains a great challenge due to its complex non-repetitive structure and the inert property for chemo-digestion. A redox-neutral lignin depolymerization system without the use of extra oxidant and/or reductant over a Co-NC catalyst has been developed in this work, providing the first non-noble metal heterogeneous catalytic system for redox-neutral valorization of lignin. Mechanistic studies based on control reactions and deuterium labeling experiments suggest that the reaction proceeds via a metal-catalyzed dehydrogenation of C α -OH to afford a carbonyl intermediate, followed by C β -O bond cleavage (via hydrogenolysis) to afford monophenols and aromatic ketone products. The hydrogen used for the cleavage of the C β -O bond originates from the alcohol moiety in the substrate, and the cascade dehydrogenation and hydrogenolysis steps are highly coupled, rendering it an efficient and atom-economic process. [ABSTRACT FROM AUTHOR]

• Efficient catalytic strategy from lignin and β-O-4 models to benzonitriles is presented. • The reaction follows a cascade C-C bond cleavage and C N bond formation pathway. • It features mild, base-free conditions, solid N source, commercially available copper catalyst and one-pot, simple transformation. • Value-added syringonitrile from birchwood lignin is afforded over cheap copper catalyst. N-participated lignin depolymerization is of great importance for the transformation of waste lignin into value-added chemicals. The vast majority of developed strategies employ organic amines as nitrogen source, and considerable methods rely on excessive use of strong base, which suffers severe environmental issues. Herein, benzonitrile derivatives are synthesized from oxidized lignin β-O-4 model compounds in the presence of solid nitrogen source (NH 4) 2 CO 3 under mild, base-free conditions over commercially available copper catalyst. Mechanism studies suggest the transformation undergoes a one-pot, highly coupled cascade reaction path involving oxidative C-C bond cleavage and in-situ formation of C N bond. Of which, Cu(OAc) 2 catalyzes the transfer of hydrogen from C β (C β -H) to C α , leading to the cleavage of C α -C β bonds to offer benzaldehyde derivative, this intermediate then reacts in-situ with (NH 4) 2 CO 3 to afford the targeted aromatic nitrile product. Tetrabutylammonium iodide (TBAI), acting as a promoter, plays a key role in breaking the C α -C β bonds to form the intermediate benzaldehyde derivative. With this protocol, the feasibility of the production of value-added syringonitrile from birchwood lignin has been demonstrated. This transformation provides a sustainable approach to benzonitrile chemicals from renewable source of lignin. A straightforward and sustainable strategy for the conversion of lignin and β-O-4 motifs into benzonitrile derivatives is presented. This facile protocol employs (NH 4) 2 CO 3 as solid nitrogen source, commercially available Cu(OAc) 2 as catalyst under air atmosphere, and undergoes a one-pot, highly coupled C-C bond cleavage and C N bond formation pathway. [Display omitted] [ABSTRACT FROM AUTHOR]

Light-degradable hydrogels have a wide range of application prospects in the field of biomedicine. However, the provision of a facile synthetic approach to light-degradable hydrogels under mild conditions remains a challenge for researchers. To surmount this challenge, a facile synthetic approach to UV-degradable hydrogels is demonstrated in this manuscript. Initially, an UV-degradable crosslinker (UVDC) having o-nitrobenzyl ester groups was synthesized in a single step through the employment of the Passerini three-component reaction (P-3CR). Both 1H NMR and MS spectra indicated the successful synthesis of high-purity UVDC, and it was experimentally demonstrated that the synthesized UVDC was capable of degradation under 368 nm light. Furthermore, this UVDC was mixed with 8-arm PEG-thiol (sPEG20k-(SH)8) to promptly yield an UV-degradable hydrogel through a click reaction. The SEM image of the fabricated hydrogel exhibits the favorable crosslinking network of the hydrogel, proving the successful synthesis of the hydrogel. After continuous 368 nm irradiation, the hydrogel showed an obvious gel-sol transition, which demonstrates that the hydrogel possesses a desirable UV-degradable property. In summary, by utilizing solely a two-step reaction devoid of catalysts and hazardous raw materials, UV-degradable hydrogels can be obtained under ambient conditions, which greatly reduces the difficulty of synthesizing light-degradable hydrogels. This work extends the synthetic toolbox for light-degradable hydrogels, enabling their accelerated development. [ABSTRACT FROM AUTHOR]

A Friedel–Crafts reaction of indolizines with 2‐aryl‐3H‐indol‐3‐ones catalyzed by B(C6F5)3 is described. This protocol gives access to indolizine derivatives that are valuable building blocks in synthetic and pharmaceutical chemistry. The reaction proceeds under mild conditions, affording various C2‐quaternary indolin‐3‐ones based on indolizine with high yields and regioselectivities. Moreover, the synthetic transformations of the target products were realized by N‐methylation and trifluoromethane sulfonation. [ABSTRACT FROM AUTHOR]

A low temperature hydrogen borrowing approach to generate secondary amines using benzimidazole-based N-heterocyclic carbene (BNHC) ruthenium complexes is reported. A series of the piano-stool complexes of the type [(η6-p-cymene)(BNHC)RuCl2] (1a-g) were synthesized via one-pot reaction of the NHC salt precursor, Ag2O, and [RuCl2(p-cymene)]2 and characterized using conventional spectroscopic techniques. The geometry of two precursors, [(η6-p-cymene)(Me4BnMe2BNHCCH2OxMe)RuCl2] (1f) and [(η6-pcymene)(Me5BnMe2BNHCCH2OxMe)RuCl2] (1g), was studied by single crystal X-ray diffraction. These catalysts were found to dehydrogenate alcohols efficiently at temperatures as low as 50 °C to allow Schiff-base condensation and subsequent imine hydrogenation to afford secondary amines. Notably, this ruthenium-based procedure enables the N-alkylation of aromatic and heteroaromatic primary amines with a wide range of primary alcohols in excellent yields of up to 98%. The present methodology is green and water is liberated as the sole byproduct. [ABSTRACT FROM AUTHOR]

The enzymatic reduction of carbon dioxide presents limited applicability due to denaturation and the impossibility of biocatalyst recovery; disadvantages that can be minimized by its immobilization. Here, a recyclable bio‐composed system was constructed by in‐situ encapsulation under mild conditions using formate dehydrogenase in a ZIF‐8 metalorganic framework (MOF) in the presence of magnetite. The partial dissolution of ZIF‐8 in the enzyme's operation medium can be relatively inhibited if the concentration of magnetic support used exceeds 10 mg mL−1. The bio‐friendly environment for immobilization does not harm the integrity of the biocatalyst, and the production of formic acid is improved 3.4‐fold compared to the free enzyme because the MOFs act as concentrators of the enzymatic cofactor. Furthermore, the bio‐composed system retains 86 % of its activity after a long time of five cycles, thus indicating an excellent magnetic recovery and a good reusability. [ABSTRACT FROM AUTHOR]

4-(Dimethylamino)-1-((4-nitrophenyl)sulfonyl)pyridin-1-ium chloride ([DMAPNS]+Cl−) has been designed based on DFT studies to have higher reactivity coupled with better stability than that of [DMAPTS]+Cl−. Accordingly, this novel reagent was prepared by using 1.0 equivalent of p-nitrobenzene sulfonyl chloride (1), 1.0 equivalent of DMAP (2) with higher yield (>99%), using sustainable approaches. The following greener techniques were optimized in the preparation of the novel reagent (i) less hazardous method (3rd principle of green chemistry), (ii) bio renewable (7th principle of green chemistry), 2-MeTHF solvent (Class 3 solvent), (iii) room temperature (6th principle of green chemistry), and (iv) column chromatography free methods (4th principle of green chemistry). [ABSTRACT FROM AUTHOR]

Research on metal salt-based deep eutectic solvent (DES) pretreatment is still in its infancy, and the effect of hydroxyl groups on Cl− in choline chloride (ChCl) is not resolved. In this study, a type IV DES composed of metal salt and glycerol (Gly) was prepared for pretreatment of moso bamboo to improve its enzymatic hydrolysis. The correlation between enzymatic hydrolysis and the contents of hemicelluloses and lignin was evaluated using the Box–Behnken design. The results showed that FeCl3-based DES was optimal among various DES. The solid recovery was reduced to 55.54% following FeCl3/Gly pretreatment, which was effective in the removal of hemicelluloses and lignin compared with ternary DES pretreatment (with ChCl) under mild conditions (100 °C, 3 h). With the increase of pretreatment temperature (120 °C, 2 h), a significant proportion of hemicelluloses (76.07%) and lignin (62.77%) was removed. The structure of FeCl3/Gly pretreatment residue was seriously damaged, and the glucose yield increased to 91.13% following enzymatic hydrolysis. This correlation indicated that the hemicelluloses' content had a significant influence on enzymatic hydrolysis of the residue following FeCl3/Gly pretreatment. This study elucidates the pretreatment effect of metal salt-based DES, which will be helpful in the value-added conversion of moso bamboo under mild conditions. [ABSTRACT FROM AUTHOR]

The selective oxidation of alkylarene is a quite straightforward and appealing way for production of aromatic aldehydes, ketones and aromatic acid derivatives. We synthesized Cr(III) catalyst, (NH4)3[CrMo6O18(OH)6], with reasonable activity towards selective oxidation of alkylarenes under mild conditions. The catalyst is supported by a central chromium mononucleus and a cyclic inorganic ligand composed of six MoVIO6 octahedra, avoiding the disadvantages of expensive and non‐recyclable organic ligand. It is efficient, green and can be recycled at least six times with high activity. At the same time, a wide range of substituted alkylarenes were found to be compatible, providing the corresponding carbonyl compounds in moderate‐to‐high yield. [ABSTRACT FROM AUTHOR]

The development of efficient bifunctional organocatalysts for the catalytic conversion of CO2 under mild conditions remains particularly challenging. Inspired by the synergistic mechanism of intramolecular Lewis acid‐base active sites, we report a series of bifunctional cross‐linked epoxy resin organocatalysts containing multiple active sites for the cycloaddition reaction of dilute CO2 with epoxides. These catalysts exhibit high reactivity and product selectivity (10 examples, >99 %) for the cycloaddition reactions of a variety of epoxides and CO2, and surprisingly, epichlorohydrin (ECH), can be converted under ambient temperature and pressure (25 °C, 1.0 bar) without co‐catalysts. 1H NMR, 13C NMR, 19F NMR and in situ IR studies suggest that the simultaneous and efficient activation of CO2 and epoxides is responsible for the improved catalytic activity. Upon an insightful investigation of the catalytic mechanism, this protocol will contribute to the development of efficient and environmentally friendly metal‐free catalysts. [ABSTRACT FROM AUTHOR]

Lignin is a natural polymer, second only to cellulose in natural reserves. Degradation is one of the ways to achieve the high-value transformation of lignin. Deep eutectic solvent (DES) thermal degradation of lignin can be used as an excellent green degradation method. This paper introduces the degradation mechanism and effect of the lactic acid-choline chloride DES system in dissolving and degrading alkaline lignin, and the final solvent recovery. It can also be found from the scanning electron microscope (SEM) images that the surface of the degraded solid product is transformed from smooth to disordered. Fourier transform infrared (FTIR) spectroscopy and 1H-NMR spectroscopy were used to characterize the changes in lignin functional groups during DES treatment. The results showed that the content of phenolic hydroxyl groups increased after degradation, indicating that the ß-O-4 ether bond was broken. The molecular weight of the degraded lignin was observed by gel permeation chromatography (GPC), and the lignin residue with low molecular weight and narrow polydispersity index was obtained. The lowest average molecular weight (Mw) reached 2512 g/mol. The ratio of oxygen to carbon atoms in lignin increased substantially during degradation as measured by X-ray photoelectron spectroscopy (XPS), probably because DES treatment was accompanied by many oxidation reactions, which led to significant structural changes in lignin and a large number of ether bond breakage reactions during the reaction. The main final degradation products are aromatic monomers, vanillin, butyrovanillone, etc. [ABSTRACT FROM AUTHOR]

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The diverse application potential of metal-organic framework (MOF) materials are currently limited by their challenging and complicated preparation processes. In this study, we successfully developed a novel strategy for the rapid synthesis of a sustainable MOF composite membrane under neutral conditions with improved physicochemical and antibacterial properties. Our reaction pipeline comprised visible light that induced the production of reactive oxygen species (ROS) from ZIF-8 particles, which facilitated the rapid oxidative polymerization of dopamine to polydopamine. The physicochemical properties of the composite membrane were assessed using imaging methods, including scanning and transmission electron microscopy, X-ray photoelectron spectrometry, and nitrogen adsorption/desorption; its antibacterial effects against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were measured using optical densitometry. The bactericidal potency of the synthesized membrane was >99% against all tested strains under the conditions of simulated sunlight. Moreover, the composite membrane retained its structural integrity and antibacterial effect after multiple cycles of use and recovery, showcasing remarkable stability. Overall, this study displays a ROS-mediated method for the rapid preparation of sustainable MOF composite membranes under neutral conditions with optimal physicochemical characteristics, antibacterial properties, and performance. Our study provides insights into the use of membrane materials as design platforms for a range of diverse practical applications. [ABSTRACT FROM AUTHOR]

Reducing the sulfur content in high-sulfur petroleum coke (HSPC) has become an urgent issue, however, remains a great challenge with the development of petroleum refining industry. Herein, a highly-efficient catalyst quaternary ammonium phosphotungstate ionic liquid [(C4H9)4N]3PW12O40 (C4@HPA) was initiated to activate H2O2, and the sulfur content of HSPC was remarkably decreased from 4.46 wt.% to 2.76 wt.% at a relatively mild temperature (70 oC), which is discernible below than 1400 oC in industry. The characterization results showed that only sulfate can be removed, while sulfoxide and sulfone were retained in petroleum coke. Moreover, the desulfurization activity of C4@HPA/H2O2 to thiophene sulfides decreases as follows: Thiophene > 2-Methylthiophene > 2,5-Dimethylthiophene > Dibenzothiophene > 4-Methyldibenzothiophene. It reveals that the sulfur of 4-MDBT is the most difficult to be removed. Therefore, this founding here may shine light on the understanding and construction of efficient catalyst for desulfurization of high-sulfur petroleum coke in industry. [ABSTRACT FROM AUTHOR]

In this work, a novel RuCo bimetallic supported on N-doped carbon support containing alumina was prepared by in-situ pyrolysis using MOF-303 as the support precursor (Ru 3 Co 1 @CN-Al 2 O 3), and it was applied to the efficient hydrodeoxygenation (HDO) of guaiacol under mild conditions (0.01 MPa H 2 , 200 °C, 3h), the yield of cyclohexanol reaches an impressive 83.12 %. In the absence of external hydrogen (2 MPa N 2 , 220 °C, 2 h), complete conversion of guaiacol was achieved, along with a remarkable 97.81 % selectivity towards cyclohexanol. The HDO of guaiacol under different atmospheres was further studied, and the possible mechanism was proposed. Characterization results indicated that the supported metals (Ru and Co) not only interacted with the N in the MOF-303 to enhance catalyst stability but also that the synergistic effect between Ru and Co was key to promoting the high yield of cyclohexanol through catalytic transfer hydrodeoxygenation (CTHDO) in isopropanol. Additionally, Ru 3 Co 1 @CN-Al 2 O 3 was also effective in achieving the HDO of macromolecular lignin. This study provides a feasible approach for the high value-added green transformation of lignin and its derivatives under mild conditions, highlighting the significant potential of MOFs for lignin valorization. [Display omitted] • MOF-303-derived N-doped carbon catalysts containing alumina were synthesized. • Achieving the directional conversion of guaiacol to cyclohexanol in isopropanol. • The yield of cyclohexanol can reach 83.12 % under mild conditions (0.01 Mpa H 2). • The complete conversion of guaiacol to 97.81 % cyclohexanol was achieved in N 2. • The HDO mechanism of catalyzing guaiacol in different atmospheres was proposed. [ABSTRACT FROM AUTHOR]

Epoxy resins rank among the most significantly used thermosets, showing high thermal and mechanical properties. Unfortunately, current polymerization processes to reach these properties are energy-intensive, characterized by high temperatures and long processing duration. Addressing this problem, recent years have witnessed the emergence of curing methods under mild and ecofriendly conditions, aligning with societal and ecological challenges. Mild conditions were delineated in this review as a polymerization without solvent and at temperatures not exceeding 80 °C. This work highlights three methods, by focusing on research works from 2015 to date: i) polyadditions via step-growth ring opening polymerization, ii) photopolymerization leading to homopolymerization of bio-based monomers and iii) redox polymerization achieved through the release of cations or acidic protons species, initiating the cationic polymerization. In the context of ecofriendly conditions, the replacement of bisphenol-A present in many epoxy monomers is also a huge challenge to keep both good mechanical properties and fast polymerization kinetics. In this context, this review aims at underlining the increasing importance of epoxy curing under mild conditions, in possible combination with bio-based monomers for bisphenol-A replacement and to guide both researchers and industries to explore and develop new curing systems. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • An atomically dispersed Ni catalyst achieved efficient ammonia synthesis under mild conditions of 101.3 kPa and 80 °C. • The catalyst produced nitrogen vacancies that activated nitrogen molecules. • The Ni-N 3 structure served as the catalytic center for hydrogen and nitrogen activation. • B element greatly promoted the uniform dispersion of Ni and better electron transfer on the surface of BCN carrier. In industry, ammonia synthesis process typically requires high temperatures (400 ∼ 500 °C) and high pressures (20 ∼ 40 MPa), resulting in high energy consumption and high carbon emissions. Exploring the direct ammonia synthesis with N 2 and H 2 under mild conditions without the assistance of electrochemical or photochemical energy, represents a promising approach. In this study, atomically dispersed Ni loaded on B-doped CN catalyst (Ni/BCN) was prepared by a liquid phase one-pot method, which achieved efficient ammonia synthesis under mild conditions of 101.3 kPa and 80 °C, with an ammonia yield of 114 μmol h−1 g cat -1 after 10 h. Further experimental studies combined with the characterization of catalyst morphology, bulk phase structure, and surface chemical state reveal the mechanism of ammonia synthesis under mild conditions. The appearance of nitrogen vacancies on Ni/BCN can promote the electron delocalization of stable N≡N bonds in N 2 , facilitating the activation of N 2. B, C and N bond with each other to form a hybrid BCN carrier, which promotes the electron transfer on the surface. Our findings suggest a general approach to engineer catalysts that can drive critical reactions pertinent to energy conservation, low-carbon, and sustainability. [ABSTRACT FROM AUTHOR]

Considering the climate, societal and health-related current and emerging issues facing the world, our group, as part of the (nano-)material science community, will play a part in providing materials and technology that can tackle these issues [...]

In the early 1990s, the seminal work by B [...]

The growing interest in green ammonia production has spurred the development of new catalysts with the potential to carry out the Haber–Bosch process under mild pressure and temperature conditions. While there is a wide experimental background on new catalysts involving transition metals, supports and additives, the fundamentals behind ammonia synthesis performance on these catalysts remained partially unsolved. Here, we review the most important works developed to date and analyze the traditional catalysts for ammonia synthesis, as well as the influence of the electron transfer properties of the so-called 3rd-generation catalysts. Finally, the importance of metal–support interactions is highlighted as an effective pathway for the design of new materials with potential to carry out ammonia synthesis at low temperatures and pressures.

A facile one-pot synthesis of 5-unsubstituted dihydropyrimidinones from β,γ-unsaturated ketoesters in low melting ʟ-(+)-tartaric acid–N,N-dimethylurea mixtures is reported. This solvent-free method is very general and provides easy access to 5-unsubstituted dihydropyrimidinone-4-carboxylate derivatives in good yields.

We report herein a photo induced Co‐catalyzed aerobic N−N coupling of diarylamines to form the corresponding tetraarylhydrazines. In this protocol, the N−N coupling reactions could be realized under mild conditions in the presence of Co(OAc)2 ⋅ 4H2O and BPhen with the irradiation of light (390–395 nm). [ABSTRACT FROM AUTHOR]

The efficient SBA-15 supported silver catalysts(Ag/SBA-15) were prepared and characterized by ICP-OES, XRD, TEM, SEM, XPS and N2 adsorption–desorption techniques. The catalysts exhibited an excellent catalytic activity for the aerobic oxidation of toluene to benzaldehyde under solvent-free conditions. Conversion of toluene and selectivity of benzaldehyde were 50% and 89% respectively over catalyst with 9.1 wt% Ag loading (10Ag/SBA-15). A wide range of substrates were tolerated under the selected reaction conditions. The kinetic study shows that the oxidation of toluene over 10Ag/SBA-15 is pseudo-first-order reaction and the activation energy Ea is 45.1 kJ/mol. A plausible mechanism involving oxygen free radicals was proposed for the aerobic oxidation reaction. Compared with the traditional method, the newly designed heterogeneous catalytic system shows better economic applicability, environmental friendliness and broader application prospects. [ABSTRACT FROM AUTHOR]

The photocatalytic conversion of plastic waste into value-added products using solar energy presents a promising approach for promoting environmental sustainability. Nonetheless, the emission of CO 2 during the conventional photocatalytic degradation process remains a major hurdle that impedes its further development. In this study, we propose an efficient photocatalytic conversion of polyethylene plastic into syngas (CO+H 2 mixtures) by using a ZnS/Ga 2 O 3 Z-scheme heterojunction photocatalyst. It is found that the strong redox capability of photogenerated holes and electrons in the Z-scheme heterojunction photocatalyst can promote the oxidative depolymerization of PE plastic, concurrently enabling the efficient reduction of the intermediate product CO 2 into syngas. Furthermore, this system also demonstrates applicability in the conversion and upcycling of other polyolefin plastics including polypropylene and polyvinyl chloride. Our findings highlight the potential of polyolefin plastics photoreforming for the production of syngas under environmentally benign conditions., (© 2024 Wiley-VCH GmbH.)

Iron-based catalysts play an important role in the ammonia industry. As one of the most abundant iron minerals, Fe 3 O 4 containing Fe II and Fe III sites is widely distributed in the earth's crust and even on exoplanets, theoretically giving it both economic and catalytic potentials in ammonia synthesis. However, in the absence of specific active co-catalyst and harsh conditions, Fe 3 O 4 is impossible to achieve ammonia synthesis alone. Here, we designed to activate the relatively inert Fe II and Fe III sites in Fe 3 O 4 with a third Fe III site inlayed in a coordination framework (MIL-101(Fe)) to achieve the unpresented multi-site collaborative catalysis. In-depth mechanism study confirmed the roles of three different Fe sites in N 2 activation, H 2 activation, and product transfer, respectively. Efficient N 2 -H 2 activation to NH 3 on the Fe 3 O 4 -based catalytic system has been achieved at extremely mild conditions. Our research provides a theoretical basis and a new strategy for designing efficient non-noble metal-based ammonia synthesis catalyst with minimized energy consumption., (© 2024 Wiley-VCH GmbH.)

This study focuses on the development of new synthetic pathways to monosubstituted biguanides from amines. An exhaustive comparison of the conditions and reagents used for biamidine transfer was performed. New reagents were synthesized and optimized conditions for the synthesis of substituted biguanides under mild conditions were developed. Eventually, two high-yielding and straightforward protocols for the transfer of a biamidine group to various amines are proposed and their scope and limitations have been explored. These conditions include: i) a direct chromatography-free procedure and ii) an eco-friendly procedure in water compatible with bioinspired molecules. They are particularly efficient for the demanding conversion of aliphatic amines.

A novel, safe, convenient and efficient protocol has been developed for regioselective chlorination of imidazo‐fused heterocycles with dichloro(4‐(trifluoromethyl)phenyl)‐λ3‐iodanes under mild conditions. The present approach avoids the need of toxic chlorinating reagents, strong stoichiometric oxidants, metal catalysts or harsh reaction conditions. 36 examples of imidazo‐fused heterocycle substrates were investigated, and the chlorinated products were obtained with moderate to excellent yields. Control experiments indicated that the chlorinated reaction proceeded through an electrophilic aromatic substitution. [ABSTRACT FROM AUTHOR]

An operationally simple protocol for the synthesis of medium‐sized lactones and macrolactones via an intramolecular ring expansion of cyclic ketones has been developed. Using this method, a series of 10‐ and 12‐membered lactones was synthesized under mild conditions. Preliminary mechanistic studies showed that a radical pathway might be involved in this reaction. [ABSTRACT FROM AUTHOR]

CO2, which causes global warming, is a naturally abundant, inexpensive, inert substance known as a non-toxic carbon (C1) source and value-added chemical, which can often be used as a building block for synthesis reactions. The conversion of CO2, which is difficult to use efficiently due to its kinetic inertia and thermodynamic stability, to cyclic carbonates with the help of a catalyst are the most promising studies. Therefore, in this study, 1-bütyl-3- methylimidazolium iodide ([Bmim]I) and 1-bütyl-3-methylimidazolium hexafluorophosphate ([Bmim]PF6) imidazolium salts were used as catalysts in the conversion of CO2 into cyclic carbonates with epoxides. Conversion studies to cyclic carbonates were carried out under both high pressure and high temperature and atmospheric pressure. Ionic liquids, which provide high efficiency in the autoclave, also gave very good results in the atmospheric ambient. Optimization studies were carried out with the effect of time (2 hours and 24 hours) and temperature (60 °C and 100 °C) in the atmospheric ambient. It has been determined that this process, catalyzed by ionic liquids, is also promising for the chemical conversion of CO2 in the atmospheric ambient. [ABSTRACT FROM AUTHOR]

A copper‐catalyzed N‐arylation of various isatoic anhydrides with diaryliodonium salts was developed by using inexpensive CuI as the catalyst under mild conditions. The method provides diverse N‐Phenylated isatoic anhydrides in high yields (up to 97%). The mechanism of the N‐arylation reaction is proposed to involve an electrophilic addition process. [ABSTRACT FROM AUTHOR]

• Synthesis of industrially important Tamsulosine intermediate under milder reaction conditions. • An overall yield of 98 %. • Better oral bioavailability, aqueous solubility, gastrointerstinal absorption. • Option "yes" in Lipinski, Ghose, Veber, Egan and Muegge rules. The present work describes a potential method for the synthesis of industrially important Tamsulosine intermediate under milder reaction conditions. The major advantages include i) nano catalytic system and ii) ammonium formate is used as greener alternative during hydrogenolysis with an overall yield of 98 %. Density functional theory (DFT) studies in combination with B3LYP exchange-correlation functional method with split valence basis set 6–311 G is used to understand molecular structure of intermediate is also described. The crystal structure of tamsulosine precursor is elucidated by using single crystal x-ray crystallography is also reported. Therefore, this study is expected to bridge the need to optimize a greener alternative process in this hydrogenolysis reaction to synthesize tamsulosin precursor. ADME studies reveals that better oral bioavailability, aqueous solubility, Gastrointerstinal absorption and option "yes" in Lipinski, Ghose, Veber, Egan and Muegge rules. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Nitrogen (N2) fixation under mild conditions is a promising approach for green production of ammonia (NH3). In the past decades, various advanced catalysts have been fabricated to achieve this goal through electrocatalytic and photocatalytic processes. Among them, the TiO2‐based catalysts have been recognized as promising candidates due to their high activity, low cost, chemical stability, and nontoxicity. In this review, recent advances in the fabrication of high‐performance TiO2‐based materials for N2 reduction reaction (NRR) under mild conditions are summarized, including electrocatalytic and photocatalytic NRR. The design principles, synthetic strategies, and corresponding chemical/physical properties of TiO2‐based NRR catalysts are described in detail. Moreover, the key challenges and potential opportunities in this field are presented and discussed.

Research on metal salt-based deep eutectic solvent (DES) pretreatment is still in its infancy, and the effect of hydroxyl groups on Cl− in choline chloride (ChCl) is not resolved. In this study, a type IV DES composed of metal salt and glycerol (Gly) was prepared for pretreatment of moso bamboo to improve its enzymatic hydrolysis. The correlation between enzymatic hydrolysis and the contents of hemicelluloses and lignin was evaluated using the Box–Behnken design. The results showed that FeCl3-based DES was optimal among various DES. The solid recovery was reduced to 55.54% following FeCl3/Gly pretreatment, which was effective in the removal of hemicelluloses and lignin compared with ternary DES pretreatment (with ChCl) under mild conditions (100 °C, 3 h). With the increase of pretreatment temperature (120 °C, 2 h), a significant proportion of hemicelluloses (76.07%) and lignin (62.77%) was removed. The structure of FeCl3/Gly pretreatment residue was seriously damaged, and the glucose yield increased to 91.13% following enzymatic hydrolysis. This correlation indicated that the hemicelluloses’ content had a significant influence on enzymatic hydrolysis of the residue following FeCl3/Gly pretreatment. This study elucidates the pretreatment effect of metal salt-based DES, which will be helpful in the value-added conversion of moso bamboo under mild conditions.

Two synthetic approaches for 5-thio- d -glucopyranose (5-TDGP) and its pentaacetates were described, focusing on different protective groups such as tert -butyldimethylsilyl and benzoyl employed to protect 3-OH. These protective groups were easily introduced from the beginning and can be removed during transformation from the corresponding mesylate of α- d -glucofuranose to 5,6-episulfide under mild conditions. In addition, a few purification manipulations were required for each approach. More importantly, 5-TDGP can be prepared using the two approaches starting from 200 g of starting material in 66.08 % and 64.4 % overall yields, respectively. [Display omitted] • Synthetic approaches for 5-thioglucose and its pentaacetate was described. • The approaches can be applied to synthesise product in hundreds--grams scale in satisfactory overall yield. • These approaches would have a broad application in the synthesis of 5-TDGP and its derivatives in carbohydrate-based drug discovery. [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation (HDO) is of great significance in converting biomass into high value‐added chemicals under mild conditions. However, the design of effective catalysts remains challenge. Herein, a N‐doped carbon nanospheres–supported Pd catalyst for mild vanillin HDO is designed by defect‐enhancement engineering using in situ synthesis. According to the characterization results, the degree of defects is enhanced on the in situ N‐doped carbon spheres (CAFR) with 3‐aminophenol as nitrogen source, which is related to the higher content of pyridine nitrogen. The Pd/CAFR with the most degree of defects exhibits excellent catalytic performance (99.8% of 2‐methoxy‐4‐methylphenol yield) at 50 °C. The plentiful defects act as active sites for anchoring Pd nanoparticles (NPs) to promote uniform dispersion. Meanwhile, the highly dispersed Pd NPs are coordinated with abundant defects through strong metal‐support interaction to increase the content of reduced Pd NPs, which improves the catalytic activity under mild conditions. Moreover, the optimal Pd/CAFR catalyst shows favorable recyclability after five cycles. The defect‐enhancement engineering on carbon materials by in situ N‐doping provides a new idea for support modification of high‐efficiency catalysts under mild conditions. [ABSTRACT FROM AUTHOR]