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• This is the first report of copper nitrate-catalyzed aerobic oxidation of 2,3-dihydroqunazolinones and 1,4-dihydropyridines without any mediators. • Copper nitrate catalyst is inexpensive, low toxicity, operational ease, and commercial availability. • Using air as the greenest, most abundant, and inexpensive oxidant, water is the only by-product formed during the oxidation reaction. • This catalyst allows for simpler (easy work-up) and greener methodologies (atmospheric pressure, room temperature) while keeping high reaction yields and easy separation. • The method conforms to several of the guiding principles of green chemistry. For the first time, copper (II) nitrate trihydrate was used as an efficient, eco-friendly, operational ease, inexpensive, and commercially available catalyst for the biomimetic aerobic oxidation synthesis of quinazolinones and Hantzsch pyridines from their corresponding 2,3-dihydroquinazolinones and 1,4-dihydropyridines, respectively. The products were achieved in satisfactory to excellent yields using acetonitrile as the solvent. These methods are considered to be more eco-friendly, efficient, uncomplicated, and useful compared to existing ones as they align with various principles of green chemistry. Hence, these techniques can be utilized in pharmaceuticals and other delicate synthesis processes. Eco-friendly aerobic oxidation of 2,3-dihydroquinazolinones and 1,4-dihydropyridines in the presence of Cu(NO 3) 2 without using any mediator under mild conditions is described. [Display omitted] [ABSTRACT FROM AUTHOR]

• A sacrifice-free method for preparing ester/lactones from the oxidation of ketones is proposed. • The α-H of ketones has been proven to be a critical factor for the initiation of the reaction. • The reaction mechanism and catalytic structure were uncovered by EPR, XRD, isotope-labeling experiments, etc. When molecular oxygen is employed as the oxidant in the Baeyer-Villiger reaction, the addition of an excess amount of sacrificial aldehyde/alcohol to generate peroxyacids or peroxides in situ is the most frequently adopted strategy. In this work, we report a sacrifice-free approach to lactone/esters from ketones using molecular oxygen as the oxidant, in which cerium ammonium nitrate and N -hydroxyphthalimide were utilized as the catalysts with a good tolerance to cyclic and aromatic ketones. Experiments have shown that the presence of α-hydrogens in ketone compounds is a critical condition for the reaction, and the 2H labeling experiments demonstrated that the oxidation is initiated via the deprivation of the α-hydrogen of ketone by phthalimide N -oxy radical (PINO), which is significantly different from the Criegee-Intermediate mechanism of traditional BV reaction. And the 18O labeling experiment suggested that NO 3 − participates in the oxidation of the carbonyl compounds and NO 3 − could be regenerated by molecular oxygen. The redox process of cerium and the structure of the catalytic complex were also illustrated by the EPR and XRD characterization. Meanwhile, cerium ammonium nitrate was proved to be capable recycle although its reactivity was decreased after two cycles. The unprecedented mechanism for the synthesis of lactone/ester was hoped to provide a new prospect in the academic study and industrial manufacture. [Display omitted] [ABSTRACT FROM AUTHOR]

• Multicomponent metal oxides (Fe 3 BiMo 8–12 O 30–42) catalysts prepared using a straightforward alkali-coprecipitation method. • Exceptional aerobic oxidation of HMF with 98 % conversion and turnover numbers (TONs) up to 379. • A high substrate to catalyst weight ratio (>2000 mmol/g). • Advanced characterisation provides insights into the active sites, structural, morphological, and surface properties of the catalyst. • One-pot, two-step process to convert fructose to DFF with > 85 % yield. Herein we report the synthesis of various of iron-bismuth-molybdenum oxides (Fe 3 BiMo 8–12 O 30–42) catalysts via a straightforward alkali-coprecipitation method. These catalyts exhibited notable highly efficiency as heterogeneous catalysts for the aerobic oxidation of HMF to DFF. Among the catalysts investigated, Fe 3 BiMo 12 O 42 (pH = 1–2) exhibited exceptional efficiency, achieving high HMF conversion (98 %) with high selectivity (>99 %) and turnover numbers (TONs) up to 379, representing 1–2 orders of magnitude improvement than previously reported non-noble catalysis systems. The Fe 3 BiMo 12 O 42 (pH = 1–2) catalyst demonstrated sustained high selectivity after five usage cycles, highlighting its practical recyclability and stability. Comprehensive characterization of the catalysts and control experiments provided insights into active sites along with the structural, morphological, and surface properties. Furthermore, a convenient one-pot, two-step process utilizing Fe 3 O 4 @SiO 2 -SO 3 H and Fe 3 BiMo 12 O 42 in tandem successfully produced DFF from fructose with an impressive overall yield of 85%, showcasing potential for sustainable and eco-friendly biomass conversion. This study presented an efficient method for converting 5-hydroxymethylfurfural (HMF) into 2,5-diformylfuran (DFF) using iron-bismuth-molybdenum oxide (Fe 3 BiMo 12 O 42) catalysts. A complete HMF conversion with remarkable selectivity (>95%) could be achieved, resulting in an impressive turnover number (TON) of up to 367. Moreover, the catalyst retained its selectivity and demonstrated good recyclability over five reaction cycles.. Comprehensive characterization of the catalysts and control experiments provided insights into active sites along with the structural, morphological, and surface properties. [Display omitted] [ABSTRACT FROM AUTHOR]

5-Hydroxymethyl-2-furancarboxylic acid (HMFCA) is an important feedstock in chemical and pharmaceutical industries. Its production through aerobic conversion of 5-hydroxymethylfurfural (5-HMF) has promising prospects but is challenged by the over-oxidation. In this work, we develop a refined Pt-Ag co-catalytic strategy to tailor the selectivity of 5-HMF's aerobic oxidation. By simple in situ addition of AgNO 3 to the thermal catalytic system of Pt nanoparticles, the main products of 5-HMF oxidation could be shifted from 2,5-furandicarboxylic acid (FDCA) to HMFCA with an ultrahigh selectivity of over 99 %. Density functional theory calculations demonstrate that such strategy could alter the HMFCA adsorption sites from Pt to Ag sites and prevent the oxidation of hydroxymethyl group. In addition, this strategy can be extended to other Ag species, such as AgCl, Ag 2 O and AgO. This work provides insights into the Pt-Ag synergistic catalysis and opens up a simple avenue to control the product selectivity for biomass refinement. [Display omitted] • A Pt-Ag co-catalytic system is constructed by in situ dosing AgNO 3 into the Pt catalytic system. • This strategy avoids complex re-design and re-synthesis of Pt catalysts for selectivity regulation. • Co-catalytic strategy shifts the main product of 5-HMF aerobic oxidation from FDCA to HMFCA. • The high selectivity is owing to the altering of HMFCA adsorption sites from Pt to Ag sites. • The co-catalytic system can be extended to other initially added Ag+ species. [ABSTRACT FROM AUTHOR]

• Co-Cu hydrotalcite catalyzes the oxidation of BHT to BHT-CHO. • Realized the efficient selection of Co1Cu3–250 °C/BHT oxidation system. • Co-Cu can form a synergistic effect to promote the deep oxidation of the reaction. • 4.Proposed the reaction path of molecular oxygen oxidation of BHT. This study investigates the application of cobalt-copper layered double hydroxides (LDHs) in the oxidation of butylated hydroxytoluene (BHT) and explores their catalytic behavior during thermal treatment. LDHs were synthesized via coprecipitation, and various ratios of Co-Cu hydrotalcite were subjected to thermal treatment. Structural analysis revealed that thermal treatment transforms the LDHs into mixed metal oxides. Among the synthesized catalysts, Co1Cu3-LDHs exhibited superior catalytic activity in the oxidation of BHT. Techniques such as XRD, FT-IR, TGA, N 2 adsorption-desorption, SEM, and XPS were employed to investigate the structural changes and surface properties of the LDHs. The Co1Cu3-LDH catalyst, treated at 250 °C, exhibited outstanding catalytic performance, attributed to the synergistic effects between Co and Cu. Upon optimizing the reaction conditions, the conversion of BHT reached 99 %, with a selectivity of 77 % towards 3,5-di‑tert‑butyl‑4-hydroxybenzaldehyde (BHT-CHO). The oxidation mechanism involves the oxidation of the π-electron system on the benzene ring and deep oxidation of the phenolic hydroxyl methyl group, with two potential reaction pathways proposed. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Multi-objective Bayesian optimization of a photocatalytic gas–liquid oxidation. • Automated flow platform for precise control of continuous variables. • Pareto front visualizes a trade-off between yield and productivity. • Algorithm enables 14-fold increase in productivity for the oxidation of tetralin. • Identified conditions of model substrate applied to a scope of 9 examples. We developed an automated platform capable of performing photochemical gas–liquid reactions. The platform was augmented with a state-of-the-art Bayesian optimization algorithm and was tested on the decatungstate-catalyzed aerobic oxidation of ethyl benzene, to optimize both yield and productivity, and identify the Pareto front of these objectives. Although photochemical gas–liquid systems are highly complex due to numerous interactions between the parameters, including effects on mass-transfer, gas solubility and light absorption, the algorithm demonstrated impressive speed to navigate the parameter space towards optimal conditions. Furthermore, this approach also proved highly flexible, allowing for modification of objectives and parameter ranges on the fly. The identified conditions were then tested on a select scope of substrates, to better understand the generality of these conditions, especially on molecules where selectivity comes into play. The results show the platform to be a useful tool for reaction optimization and process intensification. [ABSTRACT FROM AUTHOR]

The hybrid periodic mesoporous organosilica (PMO) with APTES/DAR Schiff-based precursor 3-aminopropyltriethoxysilane (APTES) and 4,6-diacetylresorcinol (DAR) was synthesized in the presence of a structure-directing agent cetyltrimethylammonium bromide and tetraethoxysilane. Then, Pd (II) ions, as well as Pd nanoparticles, were incorporated inside the pore walls of the synthesized APTES/DAR-PMO. The PMO structure was characterized by HRTEM, FT-IR, TEM, FE-SEM, BET, SEM-EDX, low angle XRD, HADAF-mapping, TGA, and atomic absorption spectroscopy (AAS). Subsequently, the as-fabricated green heterogeneous nanocatalysts (Pd-NPs@APTES/DAR-PMO) was used as effective and sustainable catalysts for the aerobic oxidation of benzylic alcohols into their corresponding aldehydes in pure water A high Pd-NPs@APTES/DAR-PMO-catalyzed conversion level of the primary and secondary alcohols was demonstrated. Furthermore, the environmentally friendly catalyst showed outstanding stability, so that readily separated by centrifugation and reused for seven consecutive cyclic terms with good retention of high catalytic activities. [Display omitted] • Engineering the mesochannel of organosilica with Schiff base frameworks. • Design of Schiff base bisylil (APTES/DAR) as a bifunctional linker. • The presence Schiff base in surface of PMO stabilizes Pd(II) ions and Pd nanoparticles. • Pd-NPs@APTES/DAR-PMO is a promising catalyst for aerobic alcohols oxidation. [ABSTRACT FROM AUTHOR]

Aerobic oxidation of bio-sourced 2,5-bis(hydroxymethyl)furan (BHMF) to 2, 5-furandicarboxylic acid (FDCA), a renewable and green alternative to petroleum-derived terephthalic acid (TPA), is of great significance in green chemicals production. Herein, hierarchical porous bowl-like nitrogen-rich (nitrated) carbon-supported bimetallic Au-Pd nanocatalysts (AumPdn/ N-BNxC) with different nitrogen content and bimetal nanoparticle sizes were developed and employed for the highly efficient aerobic oxidation of BHMF to FDCA in sodium carbonate aqueous solution. The reaction pathway for catalytic oxidation of BHMF went through the steps of BHMF→HMF→HMFCA→FFCA→FDCA. Kinetics studies showed that the activation energies of BHMF, HMF, HMFCA, and FFCA were 58.1 kJ·moL−1, 39.1 kJ·moL−1, 129.2 kJ·moL−1, and 56.3 kJ·moL−1, respectively, indicating that the oxidation of intermediate HMFCA to FFCA was the rate-determining step. ESR tests proved that the active species was a superoxide radical. Owing to the synergy between the nitrogen-rich carbon support and bimetallic Au-Pd nanoparticles, the Au1Pd1/N-BN2C nanocatalysts exhibited BHMF conversion of 100% and FDCA yield of 95.8% under optimal reaction conditions. Furthermore, the nanocatalysts showed good stability and reusability. This work provides a versatile strategy for the design of heterogeneous catalysts for the highly efficient production of FDCA from BHMF. [ABSTRACT FROM AUTHOR]

The FeCl3‐catalyzed aerobic oxidation of ketones always gives rise to the α‐C−C cleavage product, having challenges to afford hydroxyl keto compounds. Here we report an effective control of the main product from keto acid to α‐hydroxyl ketone, by reducing the concentration of FeCl3 catalyst, together with the use of DMSO as the solvent. In addition, mechanistic investigations suggested the same FeCl3‐coordinated peroxide intermediate for both hydroxylation and C−C cleavage routes, and emphasize the role of DMSO as both ligand and reductant. This work provides a new approach for selective aerobic oxidation under Lewis acid catalysis. [ABSTRACT FROM AUTHOR]

Novel Au nano-particle catalysts immobilized on both titanium(IV)- and alkylthiol-functionalized SBA-15 type ordered mesoporous silicate supports were developed. The bi-functionalized SBA-15 type support could be synthesized by a one-pot method. To the synthesized supports, Au was immobilized by the reaction of the alkylthiol groups on the supports with AuCl4−, following reduction with NaBH4. The immobilized amount and the formed structures and the electronic property of the Au species depended on the loading of alkylthiol. The moderate size (2–3 nm) nano particulate Au sites formed on Ti(0.5)-SBASH(0.5) were negatively charged. The aerobic alcohol oxidation activity of the catalysts depended on the loading of alkylthiol and the structure of the Au nano-particles. The non-thiol-functionalized catalyst (Au/Ti(0.5)-SBASH(0)) composed of the large (5–30 nm) and the higher thiol-loaded catalyst (Au/Ti(0.5)-SBASH(8)) composed of the small cationic Au species were almost inactive. The most active catalyst was Au/Ti(0.5)-SBASH(0.5) composed of the electron-rich Au nano-particles formed by the electron donation from the highly dispersed thiol groups. Styrene oxidation activity in the presence of 1-phenylethanol with O2 depended on the loadings of titanium(IV) on the Au/Ti(x)-SBASH(0.5). The titanium(IV) sites trapped the H2O2 generated through the alcohol oxidation reaction, and also contributed to the alkene oxidation by activating the trapped H2O2. [ABSTRACT FROM AUTHOR]

Benzyl alcohol (BnOH) oxidation to benzaldehyde (PhCHO) is a pivotal industrial reaction. The aerobic oxidation of BnOH in solvent-free conditions is highly compatible with the necessity of low environmental impact. In this research work, palladium oxide (PdOx) supported on ceria nanorods (CeO2-NR), was synthesized, and utilized for aerobic solvent-free oxidation of BnOH derivatives to the corresponding aldehydes. The catalyst, PdOx/CeO2-NR, was characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy/energy-dispersive spectroscopy (FE-SEM/EDS), N2 adsorption-desorption analysis, temperature-programmed reduction with hydrogen (H2-TPR), and X-ray Photoelectron Spectroscopy (XPS), proving that the PdOx (x > 1) particles were highly dispersed on CeO2-NR and have a strong interaction with the support. The PdOx/CeO2-NR catalyst permitted the aerobic oxidation of various benzyl alcohol derivatives with good conversion, and high selectivity towards the corresponding aldehydes. The presence of electron donating groups (EDG) on the benzylic ring enhanced the reactivity as opposed to the electron withdrawing groups (EWG) which were detrimental for the catalytic activity. During the reaction a partial reduction of the metal produced a Pd(0)/PdOx/CeO2-NR redox couple stable in the reaction condition, more reactive and recyclable. Some mechanistic hypotheses are presented. [ABSTRACT FROM AUTHOR]

Supported non‐noble metal catalysts for the selective oxidation of furfural into high‐value chemicals have attracted considerable attention. Herein, an atom‐level‐isolated, cobalt‐catalyst‐supported N‐doped carbon (Co SAs‐N@C) was synthesized through a metal cobalt–tannic acid coordination assembly strategy. The obtained Co SAs‐N@C with 7.68 wt% of Co content was qualitatively and quantitatively characterized by X‐ray diffraction, X‐ray photoelectron spectroscopy, high‐resolution transmission electron microscopy, high‐angle annular dark‐field scanning transmission electron microscopy, inductively coupled plasma optical emission spectrometer, and X‐ray absorption fine structure techniques. From the structural properties, potassium thiocyanate poisoning, and acid leaching, it was found that the atomic‐dispersed CoNx species of the catalyst acts as the active site and plays a vital role in its highly effective oxidative esterification activity. The catalytic mechanism of this reaction is involved in radical oxidation, as confirmed by electron paramagnetic resonance spectra. The density functional theory calculations revealed that the reaction pathway proceeds as a hemiacetal pathway. Interestingly, the Co SAs‐N@C catalyst also showed satisfactory catalytic activity for the aerobic oxidation of furfural. Unexpectedly, the Co SAs‐N@C catalyst still possessed excellent stability and recyclability without loss of activity after five reuses. [ABSTRACT FROM AUTHOR]

A MIL-53(Fe)/g-C3N4 heterogeneous composite was synthesized and applied in photocatalytic oxidation of 5-hydroxymethylfurfural (5-HMF) to 2,5-diformylfuran (DFF). The systematic investigation indicated that the introduction of MIL-53(Fe) into g-C3N4 increased the specific surface area, broadened the visible-light response region, and promoted the separation efficiency of the photo-generated electron-hole pairs. The 10% MIL-53(Fe)/g-C3N4 heterogeneous composite achieved the best photocatalytic oxidation activity with 74.5% of 5-HMF conversion under simulated sunlight, which was much higher than that of pristine g-C3N4 and MIL-53(Fe). The MIL-53(Fe)/g-C3N4 composite displayed good photocatalytic reusability and stability. Based on the characterization results and photocatalytic performance, a Z-scheme photocatalytic mechanism of the MIL-53(Fe)/g-C3N4 composite was suggested, and a possible reaction route was deduced. [ABSTRACT FROM AUTHOR]

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]

2,5-Furandicarboxylic acid (FDCA) is one of the top selected value-added chemicals, which can be obtained by the aerobic oxidation of 2,5-bis(hydroxymethyl)furfural (BHMF) over a Pd-based catalyst. However, the elucidation of the reaction mechanism was hindered by its rapid kinetics. Herein, employing the density functional theory (DFT) calculations, we delve into the detailed reaction pathways of the BHMF oxidation into FDCA over Pd(111) and PdH x (111) identifying the rate-determining steps. The results demonstrated that 2,5-diformylfuran (DFF) and 5-formyl-2-furancarboxylic acid (FFCA) are the important intermediates, while the oxidation of FFCA is the rate-limiting step with the energy barrier of 0.68 and 0.51 eV on Pd(111) and PdH 1/4 (111), respectively. By comparison of the d-band center of Pd(111) and PdH x (111) surfaces and the overall energy barrier of this reaction over these two surfaces, it makes clear that the occupation of H atoms in the Pd bulk changes the surface electronic structures and enhances the binding energy of BHMF with the PdH x surface, which consequently speeds up the conversion of BHMF into FDCA. Water plays a crucial role in facilitating the activation of O 2 via the H-transfer by constructing a hydrogen-bonding chain with the O 2 and OH*. The activation of molecular oxygen experiences enhancement through the synergy of OH* and H 2 O, resulting in the production of actomic oxygen (O*). Both O* and OH* actively participate in the BHMF oxidation, where O* improved the activation toward initial critical reaction pathways on Pd(111) while OH* exhibited its pronounced impact on the latter two key processes on both Pd(111) and PdH 1/4 (111). This study will contribute to well understanding the oxidation mechanism of BHMF into FDCA over Pd-based catalysts and establish a theoretical framework for the potential development of an effective catalyst.

The cleavage and functionalization of carbon-carbon bonds are crucial for the reconstruction and upgrading of organic matrices, particularly in the valorization of biomass, plastics, and fossil resources. However, the inherent kinetic inertness and thermodynamic stability of C-C σ bonds make this process challenging. Herein, we fabricated a glucose-derived defect-rich hierarchical porous carbon as a heterogeneous catalyst for the oxidative cleavage and esterification of C(CO)-C bonds. Systematic investigations revealed that the hierarchical porous structure enhances the adsorption of O 2 and ketones, thereby boosting the catalytic efficiency of defects. This catalyst exhibits performance comparable to that of the reported nitrogen-doped or metal nanoparticle-supported carbon materials, as well as transition metal-based homogeneous catalytic systems. This work deepens our understanding of the reaction process underlying this transformation and provides insights for designing efficient carbon-based materials for oxidative transformations., (© 2025 Wiley-VCH GmbH.)

An efficient and enantioselective aerobic oxidation of 4-substituted pyrazolones has been developed by phase transfer catalysis. Using visible light as the driving force and O2 (in air) as the oxidant, broad scopes (38 examples) of pyrazolones bearing an oxygen-attached carbon stereocenter at C-4 position were obtained in high yields (up to 98%) and excellent enantioselectivities (up to 93% ee) under mid conditions. The ready availability of catalyst, ease of operation, and low-cost and eco-friendly nature highlighted the practical utility of this visible light-promoted enantioselective aerobic oxidation.

A series of vanadium doped cryptomelane-type manganese oxide (V-OMS-2) catalysts were prepared by a simple, low-cost reflux method, and investigated for one-pot imine synthesis from oxidative coupling of benzyl alcohol and aniline with air. The physicochemical properties of the V-OMS-2 catalysts were characterized by various techniques including XRD, BET, SEM, TEM, XPS, H2-TPR and NH3-TPD. It was found that the surface area, Lewis acid sites, the amount of Mn3+ component and active surface oxygen species were much improved with vanadium doping. Consequently, the activity of V-OMS-2 catalyst for oxidative coupling of benzyl alcohol and aniline to imine was enhanced. The highest conversion and the imine yield were obtained over the 3 mol% V-OMS-2 catalyst, being ∼99% and 92%, respectively. Higher vanadium doping (≥ 6 mol%), however, hindered the preservation of OMS-2 crystal structure, leading to a drop in the catalytic performance. The high specific surface area was suggested to be the key contributor to the high catalytic activity of 3% V-OMS-2(1) catalyst. Among the vanadium precursors studied, the catalyst prepared with vanadium pentoxide exhibited a much higher catalytic activity, which can be attributed to its larger surface area, unique mesoporous structure, increased Lewis acid sites and more readily available surface oxygen species. In addition, the stability and recyclability of the catalyst were also studied, and the reaction mechanism was discussed.

A sustainable photochemical protocol for the oxidation of alcohols to ketones and carboxylic acids has been developed by using 2,4,6‐triphenylpyrylium tetrafluoroborate (TPPT) as organophotocatalyst and molecular oxygen as oxidant under visible light irradiation. The key reactive oxygen species, superoxide (O2•−) for the first oxidation step from alcohol to aldehyde and singlet oxygen (1O2) for the second oxidation step from aldehyde to carboxylic acid, were generated successfully by electron transfer and energy transfer pathways, respectively. A range of primary and secondary alcohols were converted to the corresponding carboxylic acids or ketones, and the optimized reaction conditions were applied to the synthesis of benzocoumarin. [ABSTRACT FROM AUTHOR]

The synthesis and functionalization of nitrogen‐containing compounds continue to be important due to their wide applications. In particular, the preparation of nitriles and amides applying cost‐effective and green methodologies is of central importance because these products represent valuable fine and bulk chemicals and serve as key precursors and central intermediates in organic synthesis and drug discovery as well as materials. Here, the preparation of nitriles and primary amides from alcohols and ammonia by a heterogeneous Cu‐catalyzed aerobic oxidation process is reported. The optimal catalyst for this synthesis is based on supported copper oxide‐nanoparticles, which are prepared by the impregnation and pyrolysis of simple copper nitrate on carbon. Applying these reusable nanoparticles, various simple, substituted, and functionalized aromatic, heterocyclic, and aliphatic nitriles are synthesized starting from inexpensive and easily accessible alcohols and ammonia in the presence of air. In addition, the synthesis of selected primary amides in a water medium is also performed using these Cu nanoparticles. [ABSTRACT FROM AUTHOR]

A base-mediated aerobic oxidation of alkylbenzimidazoles for the preparation of carboxylic acids is described. A number of aliphatic carboxylic acids have been prepared in good to excellent yields via a C–C bond rupture process. Preliminary mechanistic studies suggest the reaction undergoes a radical pathway initiated by strong bases such as potassium amide. This type of transformation provides an alternative strategy for the access of important carboxylic acid moieties. [ABSTRACT FROM AUTHOR]

The photoirradiation of toluene derivatives with two equivalents of bromine in benzotrifluoride–water provided a satisfactory yield of the corresponding benzoic acid derivatives. Either a fluorescent lamp, blue LED (454 nm), or UV LED (385 nm) was used for the photoreaction. The reaction pathway might proceed through the dibromination of benzylic carbon, generation of the benzylic radical via oxidative C–H abstraction, formation of benzoyl bromide, and hydrolysis of carboxylic acid. [ABSTRACT FROM AUTHOR]

An aerobic phosphorylation of N‐aryltetrahydroisoquinolines was realized by SbCl3 initiated sp3 C−H bond functionalization, providing a series of α‐aminophosphonates in high yields. This work reveals that SbCl3/O2 is an efficient and facile catalyst system to enable the aerobic C−H functionalization, and antimony containing reagents might be potentially applied to more general transformations. [ABSTRACT FROM AUTHOR]

[Display omitted] • In the 3D Mn-MOF structure, each two Mn(II) ion centers are coordinated with five or four oxygen atoms to form a 1D chain structure. • The 1D chains are linked one to another via ligands to form a 3D framework that generates 3D channels of rhombic aperture. • The Mn-MOF shows high catalytic activity on the aerobic oxidation of benzyl alcohol via the generation of O 2 •− under 420 nm light irradiation. • The Mn-MOF exhibits well efficiency in the trifluoromethylation of different arenes by the formation of the CF 3 • as an intermediate. The design and synthesis of multifunctional metal–organic frameworks (MOFs) has been widely attentions and certain challenges. In this work, we successfully synthesized and designed a 3D Mn-MOF ([Mn 4 (L) 4 (DMF) 3 ] n (Mn-MOF), L = 4,4′-(anthracene-9,10-diyl)dibenzoic acid). Structural analysis suggests that the Mn(II) ions in each one-dimensional (1D) arrangement are evenly distributed on both sides of the central pseudoatomic column, and each two Mn(II) ion centers are coordinated with five or four oxygen atoms from five or four L ligands to form a 1D chain structure. The 1D chains are linked one to another via ligands to form a 3D framework that generates 3D channels of rhombic aperture. In this work, the anthracene group with conjugated structure was successfully inserted into the highly porous stable Mn-MOF , which showed obvious photoactivity. In photocatalytic studies, Mn-MOF not only shows high catalytic activity on the aerobic oxidation of benzyl alcohol via the generation of O 2 − under 420 nm light irradiation but also exhibits well efficiency in the trifluoromethylation of different arenes by the formation of the trifluoromethyl radical (CF 3 ) as an intermediate. Mn-MOF has high recoverability and applicability to various substrates, which makes it a potential photocatalyst. [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]

A low transition temperature mixture formed with 1‐butyl‐3‐(methoxycarbonylmethyl)imidazolium chloride and iron(III) chloride has proven to be an efficient catalyst for the synthesis of quinazolines following a sequence of condensation‐cyclization‐oxidation reactions. The protocol is simple and effective for coupling 2‐acylanilines and benzylamines to form nitrogen containing heterocycles with moderate to excellent yields (up to 93 %), being possible to perform the reaction in preparative scale. The functionalized imidazolium salt is crucial for the activation of the reagents under solvent‐free conditions, and the presence of iron in the catalyst mediates the oxidation step with atmospheric oxygen. These features make the presented procedure better, from an environmental point of view, than other processes previously described. For this comparison, different "green" metrics have been used, such as atom economy, stoichiometric factor, reaction mass efficiency, E‐factor, and EcoScale. [ABSTRACT FROM AUTHOR]

The article presents an in‐depth study of the applicability of cooperative [M]‐/Organo‐catalytic systems in aerobic Si−H‐functionalization. A thorough kinetic study allowed us to identify two "complementary" catalytic systems based on earth‐abundant [M]‐catalysts and inexpensive commercially available organic catalysts. The first system, Co(OAc)2/N‐hydroxysuccinimide, made it possible to oxidize a Si−H‐group to a Si−OH‐group in a wide range of monomers, including previously unknown ones, that dramatically differ in their reactivity. However, this system failed in the case of oligomeric and polymeric substrates. This problem was solved by application of the Cu(OAc)2/N‐hydroxyphthalimide system. A wide potential for gram‐scale (50–100 g) preparation of Si−OH‐containing products with molecular architectures of different complexity was revealed using the established "substrate‐reactivity‐catalytic system" relationship. In particular, previously unknown types of dumbbell‐shaped and graft polymers were synthesized using alkoxysilanols. [ABSTRACT FROM AUTHOR]

Background: As a metabolic disease, any abnormality in the aerobic oxidation pathway of glucose may lead to the occurrence of diabetes. This study aimed to investigate the changes in proteins related to aerobic oxidative metabolism in urinary exosomes of diabetic patients and normal controls of different ages, and to further verify their correlation with the pathogenesis of diabetes. Methods: Samples were collected, and proteomic information of urinary exosomes was collected by LC-MS/MS. ELISA was used to further detect the expression of aerobic and oxidative metabolism-related proteins in urinary exosomes of diabetic patients and normal controls of different ages, and to draw receiver operating characteristic (ROC) curve to evaluate its value in diabetes monitoring. Results: A total of 17 proteins involved in aerobic oxidative metabolism of glucose were identified in urinary exosome proteins. Compared with normal control, the expressions of PFKM, GAPDH, ACO2 and MDH2 in diabetic patients were decreased, and the expression of IDH3G was increased. The concentrations of PFKM, GAPDH and ACO2 in urinary exosomes were linearly correlated with the expression of MDH2 (P<0.05). These four proteins vary with age, with the maximum concentration in the 45-59 age group. PFKM, GAPDH, ACO2, and MDH2 in urinary exosomes have certain monitoring value. When used in combination, the AUC was 0.840 (95% CI 0.764-0.915). Conclusions: In diabetic patients, aerobic oxidative metabolism is reduced, and the expression of aerobic oxidative metabolism-related proteins PFKM, GAPDH, ACO2, and MDH2 in urinary exosomes is reduced, which may become potential biomarkers for monitoring changes in diabetes. [ABSTRACT FROM AUTHOR]

The present study focused on developing a stable basic MnOx support for Ru (RuMn) for the efficient oxidation of 5‐hydroxymethylfurfural (HMF) to 2,5‐furandicarboxylic acid (FDCA) in water in the absence of an external base. A series of MnOx supports, synthesized via hydrothermal approach using urea as precipitant, was prepared by thermal treatment at various temperatures (300–800 °C) before doping with Ru. The RuMn‐2 (1 wt % Ru, MnOx calcined at 400 °C) possessed a large number of basic sites (1.72 mmol g−1) based on CO2 temperature‐programmed desorption analysis, affording an FDCA yield of 87 % with a turnover frequency of 22 h−1. Transmission electron microscopy energy‐dispersive X‐ray spectroscopy elemental mapping of RuMn‐2 showed a high dispersion of Ru over the surface of MnOx, contributing to the efficient HMF oxidation. Moreover, X‐ray diffraction, X‐ray photoelectron spectroscopy, and H2 temperature‐programmed reduction indicated that the predominant MnO2 phase (ϵ‐MnO2) played a vital role in HMF oxidation. RuMn‐2 was recyclable for up to four runs without significant loss in the activity and retained its structural integrity. [ABSTRACT FROM AUTHOR]

Ferrocenium-doped manganese(IV) oxide (Fc+ /MnO2) was synthesized through accelerated decomposition of KMnO4 in the presence of ferrocenium ion (Fc+) generated by concentrated sulfuric acid. The corresponding catalysts enabled highly efficient oxidation of alcohols with aldehyde or ketone. [ABSTRACT FROM AUTHOR]

2-(2-Pyridyl)benzimidazole (PyBzIm) was supported onto magnetic mesoporous silica, Fe3O4@SiO2@SBA-15 via the click chemistry. The supported ligand was treated with Na2PdCl4 in methanol to afford Fe3O4@SiO2@SBA-PyBzIm-Pd(II) as a magnetically retrievable supported catalyst. The catalyst was fully characterized by conventional methods. X-ray photoelectron spectroscopy (XPS) studies confirmed some C = N nitrogen atoms interact with palladium in the + 2 oxidation state. The prepared catalyst was found to catalyze the aerobic oxidation of benzyl alcohols and benzaldehydes to the corresponding benzoic acids, and excellent conversions were obtained. The magnetic catalyst showed a very low metal leaching (3.9%) in the first run. Fe3O4@SiO2@SBA-PyBzIm-Pd(II) was then treated with aqueous NaBH4 to give Fe3O4@SBA-PyBzIm-Pd(0). The obtained catalyst was found to catalyze the transfer hydrogenation of nitroarenes to the corresponding anilines in the presence of hydrazine, and excellent yields were obtained. The prepared catalysts present an excellent recycling efficiency over seven consecutive runs without significant loss of catalyst reactivity. [ABSTRACT FROM AUTHOR]

Direct aerobic oxidation of p-xylene using cobalt, manganese and bromide ion catalyst system, named the Amoco method, is a fundamentally important process to produce terephthalic acid in industry. However, it still suffers from harsh conditions and potential environmental pollution. Herein, we disclose an aerobic oxidation of alkyl aromatics to carboxylic acids through decatungstate photocatalysis featuring mild and green conditions (i.e., ambient temperature, visible light irradiation and atmospheric O2 as the green oxidant). It is scalable for the synthesis of terephthalic acid, which shows a significant potential for industrial production. Various substituted toluene derivatives were well applicable, thus furnishing acid and ester products in good yields.

The development of green and sustainable oxidative reactions demands efficient catalyst to harness molecular oxygen as a terminal oxidant. In present work, a specific hybrid photocatalyst was rational designed upon covalent grafting a cobalt molecular complex as the electron transfer mediator to mesoporous carbon nitride through an amide linkage. This nanostructured bifunctional photocatalyst was characterized by various spectroscopic techniques and proved to be a selective and efficient catalyst for photocatalytic visible-light-driven aerobic oxidations of organic molecules. This strategy provides efficient electronic communication between the molecular catalyst and semiconductive material, therefore opens a pathway for photocatalytic aerobic oxidations in chemical synthesis.

The aerobic oxidation of methane (CH4) by methanotrophic bacteria (MOB) is the major sink of this highly potent greenhouse gas in freshwater environments. Yet, CH4 oxidation is one of the largest uncertain components in predicting the current and future CH4 emissions from these systems. While stable carbon isotopic mass balance is a powerful approach to estimate the extent of CH4 oxidation in situ, its applicability is constrained by the need of a reliable isotopic fractionation factor (αox), which depicts the slower reaction of the heavier stable isotope (13C) during CH4 oxidation. Here we explored the natural variability and the controls of αox across the water column of six temperate lakes using experimental incubation of unamended water samples at different temperatures. We found a large variability of αox (1.004–1.038) with a systematic increase from the surface to the deep layers of lake water columns. Moreover, αox was strongly positively coupled to the abundance of MOB in the γ-proteobacteria class (γ-MOB), which in turn correlated to the concentrations of oxygen and CH4, and to the rates of CH4 oxidation. To enable the applicability in future isotopic mass balance studies, we further developed a general model to predict αox using routinely measured limnological variables. By applying this model to δ13C-CH4 profiles obtained from the study lakes, we show that using a constant αox value in isotopic mass balances can largely misrepresent and undermine patterns of the extent of CH4 oxidation in lakes. Our αox model thus contributes towards more reliable estimations of stable carbon isotope-based quantification of CH4 oxidation and may help to elucidate large scale patterns and drivers of the oxidation-driven mitigation of CH4 emission from lakes.

A ReSe 2 /ZnIn 2 S 4 heterostructure is designed for anaerobic dehydrogenation of p-toluenethiol (PTT) into p-tolyl disulfide (PTD) and H 2 , which realizes the simultaneous utilization of photogenerated electrons and holes and establishes a closed-loop system with zero waste discharge. [Display omitted] • ReSe 2 /ZnIn 2 S 4 is first constructed for photocatalytic dehydrogenation of thiols. • Cooperative S-S coupling and H 2 production is realized devoid of waste discharge. • The emergence of the robust IEF drives the spatial charge separation. • ReSe 2 provides active sites to promote H 2 evolution and enhances thiols adsorption. • The ReSe 2 /ZnIn 2 S 4 delivers 5 times higher photocatalytic activity than the blank ZIS. Photocatalytic anaerobic dehydrogenation provides a new avenue to cooperatively produce clean fuels and fine chemicals, while minimizing waste discharge and reducing environmental impact. Here, we demonstrate an efficient co-production of disulfides and H 2 via photocatalytic S-S dehydrogenation of thiols using a two-dimensional (2D) heterostructure of ultrathin ZnIn 2 S 4 (ZIS) nanosheets decorated with dispersed (1T phase) ReSe 2 nanoparticles. Experimental characterizations and DFT calculations reveal that integrating ReSe 2 with ZIS leads to the formation of a robust internal electric field (IEF) within the ReSe 2 /ZIS heterostructure. The distorted 1T phase ReSe 2 with abundant active Se sites and a high Fermi level induces downward band bending of ZIS at the interface, which promotes charge separation and expedites H 2 evolution. Moreover, the introduction of ReSe 2 provides more adsorptive sites, increasing the concentration of reactants on the catalyst surface. This enhancement fosters surface interactions between the catalyst and p-toluenethiol (PTT), ultimately accelerating the reaction rate. The optimal H 2 and S-S coupling p-tolyl disulfide (PTD) production rates of the 5 wt% ReSe 2 /ZIS composite reach 2275 and 2303 µmol g−1h−1, respectively, approximately 5 times greater than those of blank ZIS. Importantly, the selectivity of PTD reaches 98.4 %. This visible-light-driven dehydrogenation process aligns with the principles and objectives of green chemistry, realizing high atom economy without generating byproducts. It is anticipated to open new sustainable and friendly routes for synthesizing high-value chemicals and producing clean energy. [ABSTRACT FROM AUTHOR]

• The MCM-41-Phen-CuCl complex is first prepared and characterized. • MCM-41-Phen-CuCl exhibits a comparable catalytic activity to CuCl/Phen system. • The aerobic oxidation reaction gives a range of aldehydes or ketones in high yields. • The copper catalyst can be recycled up to 8 cycles with almost consistent activity. A new 1,10-phenanthroline-functionalized MCM-41-immobilized copper(I) complex [MCM-41-Phen-CuCl] was prepared from 1-(1,10-phenanthrolin-5-yl)-3-(3-(triethoxysilyl)propyl)urea via immobilization on MCM-41, followed by reacting with copper(I) chloride. It was found that this heterogenized copper(I) complex is a highly efficient catalyst for the oxidation of a wide variety of alcohols into aldehydes and ketones using molecular oxygen as the stoichiometric oxidant and 5 mol% of di- tert -butyl hydrazine-1,2-dicarboxylate (DBAD-H 2) as additive, and can be recycled more than eight cycles with almost consistent activity. [Display omitted] [ABSTRACT FROM AUTHOR]

• Facile synthesis of thiosulfonates. • The strategy is simple and substrate scope compatibility. • Metal-free catalysis and tert ‑butyl nitrite was used as an important additive. Thiosulfonate derivatives have shown a broad spectrum of biological activities and are used as powerful synthon in synthetic organic chemistry. As a consequence, oxidative reactions reactios of thiophenols have received colossal interest. Herein, a concise route for the synthesis of thiosulfonates has been disclosed through aerobic oxidation of thiophenol under metal-free reaction conditions. In this strategy, tetrabutylammonium iodide was used as a catalyst and tert‑butyl nitrite with air were used as oxidants to construct a series of thiosulfonate derivatives (up to 86 % yield). This synthetic reaction could also be carried out at 5 mmol scale and the target product was obtained in 79 % yield. A series of control experiments and EPR characterization were carried out to demonstrate that the reaction went through a free radical process. A possible reaction mechanism was proposed. To create your abstract, type over the instructions in the template box below. Fonts or abstract dimensions should not be changed or altered. [Display omitted] [ABSTRACT FROM AUTHOR]

• A new and simple process route for the synthesis of hexamethylenediamine(HMDA) from 6-hydroxyhexanenitrile in a two-step reaction was proposed for the first time. • A heterogeneous bimetallic catalyst Ni 30 Co 7 /SiO 2 was found to be efficient in the reductive amination of 5-CPA to HMDA through catalyst screen and reaction parameter optimization. • This novel protocol shows great application prospects for the manufacture of HMDA due to the easy availability and low toxicity of the raw materials, as well as its green characteristics. Hexamethylenediamine (HMDA) is an important chemical product for the production of various value-added chemicals especially in the manufacture of polyamides, and its current production mainly relies on the hydrogenation of adiponitrile (ADN). However, the processes for the production of ADN are complicated and monopolized by some transnational corporations. In this work, a novel two-step synthesis of HMDA, consisting of the aerobic oxidation of 6-hydroxyhexanenitrile (6-HHN) to 5-cyanopentanal (5-CPA) and the reductive amination of 5-CPA to HMDA, has been developed. The aerobic oxidation of 6-HHN to 5-CPA was readily realized in an excellent yield of 92.2% under the catalysis of a classic catalyst system Fe(NO 3) 3 /4-AcNH-TEMPO/NaCl under mild conditions. The reductive amination of 5-CPA to HMDA was conducted over a bimetallic Ni 30 Co 7 /SiO 2 , and the conversion of 5-CPA was 99.0% with a HMDA selectivity of 89.5% under optimal parameters. The characterization results show that Ni and Co are mainly present in the form of a Ni-Co alloy. The formation of the Ni-Co alloy in the catalyst Ni 30 Co 7 /SiO 2 endows with a synergistic effect between Ni and Co in the reductive amination of 5-CPA to HMDA. Catalyst deactivation occurs during catalytic run. Deactivation is mainly due to the metal agglomeration, the oxidation of Ni0 to Ni2+, and the carbon deposition. Deactivated catalysts can be completely regenerated by H 2 high-temperature reduction. [Display omitted] [ABSTRACT FROM AUTHOR]

• 37 Substrates. • Gram scalability. • Flavin was first used to catalyze oxidizing alkanes to ketones. • Applied to many bioactive, pharmaceutical molecules and natural products. • Moderate-to-excellent yields with good functional group tolerance. A protocol of flavin-catalyzed, TBHP-promoted aerobic oxidation of (het)aryl alkane to ketones has been developed and the products were provided in moderate-to-excellent yields with broad functional group tolerance. Flavin was first employed as a catalyst to oxidize (het)aryl alkane to ketones. The methodology were applied to the synthesis of many biologically active, pharmaceutical molecules and natural products. Mechanistic investigation reveals that a radical pathway may be involved in the transformation. [Display omitted] [ABSTRACT FROM AUTHOR]

Reagent and catalyst-free dehydrogenation (aromatization) of 2, 3-dihydroquinolones under aerobic oxidation is reported. This protocol involves metal-free synthesis of 4-quinolones from easily accessible stating materials in mixture of xylenes as solvent at 130 °C for 3–6 days. No chromatography purification and workup procedures are not needed. The product solidified in pure state from the reaction mixture and unreacted starting material remain in solution. The yields are up to 95 %. This methodology will be accessible to synthesize some 4-quinolone alkaloids. [Display omitted] • Reagent and catalyst-free dehydrogenation (aromatization) of 2, 3-dihydroquinolones under aerobic oxidation. • This protocol involves metal-free synthesis of 4-quinolones from easily accessible stating materials in mixture of xylenes as solvent at 130 °C for 3–6 days. • No chromatography purification and workup procedures are not needed. • The yields are up to 95 %. This methodology will be accessible to synthesize some 4-quinolone alkaloids. [ABSTRACT FROM AUTHOR]

Crop development is used to address environmental problems in the industry. Environmental pollutants, particularly humble or toxic chemicals and dyes, are contaminants in industrial wastewater. Recently, green technology has become important for controlling the chemical risks associated with environmental issues. This study focused on valuable crop materials to form green catalysts that can be used to control chemical toxicity in industrial wastewater. In this study, Musa acuminata -free tepal (MAFT) crops and musa were used to mediate the formation of copper nanocatalyst for environmental pollution. The synthesised nanocatalyst was analysed by XPS, XRD, TEM, SEM, FT-IR, GC-EI-MS, and TGA-DSC. The production of Cu–O in the 512 cm−1 peak range was verified by FT-IR analysis. The XRD peaks associated with the cubic crystalline structures of copper (110) and (200) were used to confirm the Musa acuminata-free tepal CuO nanocatalyst. The SEM images of the Cu and CuO nanocatalyst in the Musa acuminata free tepal showed that the particles were almost spherical. The size of the synthesised Musa acuminata free tepal CuO nanocatalyst core-shell nanostructures was identified using HR-TEM. GC-MS investigations also verified the aerobic oxidation of the main alcohol to aldehyde, with a retention time of 30.34. The MAFT was 80 % of CBB G250 dye decolourised at 24 h, and the MAFT-CuO nanocatalyst was decolourised the CBB G250 dye at 80 % in 20 min and aerobic oxidation at the same time (dual application). Furthermore, our nanocatalyst could be effectively recycled without significant loss of catalytic activity, and the use of safe, environmentally benign MAFT-Cu and CuO nanocatalyst is considered a green chemistry approach that helps avoid wastewater treatment. MAFT-Cu and CuO nanocatalyst were successfully synthesised using Musa acuminata free tepal extract assisted by reflux sample preparation system instruments as a new, green, eco-friendly, and fast process for nanocatalyst synthesis. In the past, there have been no reported applications of MAFT-Cu and CuO nanocatalyst for decolourisation and aerobic oxidation. Nevertheless, we were able to accomplish these procedures with the help of CuO and MAFT-Cu nanocatalyst. Therefore, the most effective naturally occurring environmental catalysts for aerobic oxidation processes are MAFT-CuO nanocatalyst. They are non-toxic and environmentally benign, exhibit strong aerobic oxidation catalytic performance, and have long-lasting benefits for water quality. Additionally, they are more recoverable and biodegradable. [Display omitted] • Collection of Musa acuminata free tepal crop and Synthesis of Musa acuminata free tepal crop with CuO NPs (MAFT-CuO). • Characterisation of FT-IR, UV-Visible spectroscopy, XRD, XPS, TEM, SEM, GC-MS, and TGA, etc. • Aerobic Oxidation of alcohol dehydration and Dye Decolourization via eco-friendly method. • Musa acuminata free tepal crop used for dye decolouration. • MAFT-CuO used for dual application in dye decolouration and aerobic oxidation. [ABSTRACT FROM AUTHOR]

A convenient dehydrogenation of a number of N,O‐containing heterocycles and carbocycles with readily available inorganic base (KOtBu) and oxygen is reported. The oxidation process is proved to be an SRN1 pathway followed by a radical elimination. This radical process has opened up the possibilities for the development of new superoxide mediated synthetic methodologies using KOtBu as the single electron reductant. [ABSTRACT FROM AUTHOR]

A one‐pot synthesis of 2‐imino‐1,3,4‐thiadiazolines was successfully achieved under mild conditions. The developed synthesis involves Fe(Pc)‐catalyzed aerobic oxidation of acylhydrazides followed by P(NMe2)3‐mediated annulation of the in situ generated N‐acyldiazene with isothiocyanates. The present annulation showed broad substrate scope with good functional group tolerance, and was effective on gram scale. [ABSTRACT FROM AUTHOR]

The previous strategies for oxidative cleavage of 2,3‐double bond of substituted indoles generally suffered from usage of heavy metals, stoichiometric chemical oxidants or hash conditions. Herein, we reported an electrochemistry‐driven aerobic cleavage of C(2)=C(3)/C(2)−N bonds of indoles. Through an undivided cell, various indoles and its derivatives can be converted into the corresponding ortho‐amino aryl ketones. This method features metal‐free, air‐as‐oxidant and easy scalability. [ABSTRACT FROM AUTHOR]

A simple copper catalyzed "one‐pot" process has been developed for synthesis of polysubstituted imidazoles via direct oxidative N‐α‐C(sp3)‐H functionalization of arylmethylamines. The readily available arylmethylamines as a substrate have afforded tetrasubstituted imidazoles products up to 94% yields under mild and environmentally benign conditions. The explored substrates scope with 1,2‐diketones and α‐hydroxyketones have shown great utility for synthesis of tetrasubstituted imidazoles. [ABSTRACT FROM AUTHOR]

Based on C−H activation relay (CHAR), a TBN/O2‐initiated C(sp3)−H multifunctionalization of α‐cyanotetrahydroisoquinolines was developed. This reaction is superior with mild reaction conditions and good functional group tolerance, avoiding the use of strong oxidants to oxidize the inert C(sp3)−H bond. [ABSTRACT FROM AUTHOR]

Herein, a one‐dimensional hollow nanofiber catalyst composed of tightly packed multiphase metal oxides of Mn2O3 and Cu1.4Mn1.6O4 was constructed by electrospinning and tailored thermal treatment procedure. The characterization results comprehensively confirmed the special morphology and composition of various comparative catalysts. This strategy endowed the catalyst with abundant interfacial characteristics of components Mn2O3 and Cu1.4Mn1.6O4 nanocrystal. Impressively, the tuning thermal treatment resulted in tailored CuI sites and surface oxygen species of the catalyst, thus affording optimized oxygen vacancies for reinforced oxygen adsorption, while the concomitant enhanced lattice oxygen activity in the constructed composite catalyst ensured the higher catalytic oxidation ability. More importantly, the regulated proportion of oxygen vacancy and lattice oxygen in the composite catalyst was obtained in the best catalyst, beneficial to accelerate the reaction cycle. Compared to other counterparts obtained by different temperatures, the CMO‐500 sample exhibited superior selective aerobic 5‐hydroxymethylfurfural (HMF) oxidation to 2,5‐furandicarboxylic acid (FDCA, 96 % yield) in alkali‐bearing aqueous solution using O2 at 120 °C, which resulted from the above‐mentioned composition optimization and interfacial engineering reinforced surface oxygen consumption and regeneration cycle. The reaction mechanism was further proposed to uncover the lattice oxygen and oxygen vacancy participating HMF conversion process. [ABSTRACT FROM AUTHOR]

The efficacy of synthetic methodologies is based not only on potent chemistries but also on processing strategies that amplify reaction performance and overall safety. The N‐hydroxyphtalimide‐catalyzed aerobic oxidation of aldehydes is an environmentally reliable and inexpensive approach for the synthesis of valuable carboxylic acids. However, the reaction may lead to the accumulation of significant amounts of peracid in crude product mixtures thereby generating a considerable safety hazard. Also, in the case of deactivated substrates, long reaction times, high catalyst loading, and stoichiometric additives are required to promote oxidation. Therefore, we developed a flow chemistry‐based process for N‐hydroxyphtalimide‐catalyzed aldehyde oxidations and exploited its benefits to minimize peracid buildup, thereby enhancing the process safety. By performing the aerobic oxidation of aldehydes under continuous flow conditions, chemically intensified and scalable carboxylic acid formation was obtained even in the reactions of deactivated substrates. Our findings are presented herein. [ABSTRACT FROM AUTHOR]