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This article discusses the use of photoredox catalysts in organic synthesis, specifically focusing on the activation of inert C-H bonds through hydrogen atom transfer. The authors examine the synthesis of carboxylic acid derivatives using a homemade reactor and various organic photocatalysts. They analyze the effects of different substituents on the reactivity of aldehydes and discuss the factors that influence the reaction outcome. The study also explores the photocatalytic aerobic photooxidation of benzaldehyde to benzoic acid using different organic dyes as photocatalysts, finding that 2-chloroanthraquinone under home white-light lamps resulted in efficient conversion. The study provides insights into the photocatalytic activity of anthraquinones and offers guidelines for reproducibility and further exploration of environmentally friendly methodologies. [Extracted from the article]

Simple Summary: Canine mammary cancer (CMC) is the most prevalent neoplasm in intact female dogs, with approximately 50% of these cases diagnosed as malignant. Various chemotherapeutic agents have been applied in CMC treatment, but these agents come with notable disadvantages and limited information on efficacy. The benzo[6,7]oxepino[3,2-b] pyridine (BZOP) derivative, 2-((2-methylpyridin-3-yl)oxy)benzaldehyde (MPOBA), exhibited potent anticancer activity against a human colorectal cancer cell line. However, the anticancer effects and molecular mechanisms of MPOBA on CMC have not been elucidated. This study investigated the effects of MPOBA on proliferation, migration, and apoptosis and investigated its potential mechanism in two CMC cell lines, REM134 canine mammary carcinoma and CMGT071020 canine mammary tubulopapillary carcinoma. Furthermore, an in vitro cytotoxicity test was also evaluated in the Madin–Darby canine kidney (MDCK) cell line. The results revealed that MPOBA significantly inhibited proliferation and migration and induced apoptosis in CMC cell lines. In addition, MPOBA showed lower cytotoxicity in MDCK cells. According to the gene expression analysis, the mRNA expression levels of TP53 tumor suppressor (TP53), Bcl-2 associated X (BAX), and B-cell lymphoma-2 (BCL-2) in both CMC cells were significantly altered in the treatment groups compared to the control. These results suggested that MPOBA may have induced apoptosis in both CMC cell lines. This effect may be mediated through the downregulation of BCL-2 and upregulation of BAX gene expressions. These findings indicated that MPOBA may serve as an emerging candidate agent for CMC treatment. However, mRNA expression levels may not be directly proportional to protein expression levels. Therefore, additional studies, including apoptosis-related protein analysis and apoptosis marker assays, are required to confirm the major apoptosis signaling pathway regulated by MPOBA. CMC is the most frequently diagnosed cancer and one of the leading causes of death in non-spayed female dogs. Exploring novel therapeutic agents is necessary to increase the survival rate of dogs with CMC. MPOBA is a BZOP derivative that has a significant anticancer effect in a human cell line. The main goal of this study was to investigate the anticancer properties of MPOBA against two CMC cell lines (REM134 and CMGT071020) using a 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, a wound healing assay, a transwell migration assay, an Annexin V-FITC apoptosis assay with a flow cytometry analysis, a mRNA expression analysis using quantitative real-time PCR (qRT-PCR), and an immunohistochemistry (IHC). According to the accumulated studies, MPOBA caused significant concentration- and time-dependent reductions in cell proliferation and cell migration and induced apoptosis in both CMC cell lines. In gene expression analysis, nine canine genes, including TP53, BCL-2, BAX, epidermal growth factor receptor (EGFR), snail transcription factor (SNAIL), snail-related zinc-finger transcription factor (SLUG), TWIST, E-cadherin, and N-cadherin, were investigated. The mRNA expression results revealed that MPOBA induced upregulation of TP53 and overexpression of the pro-apoptotic gene BAX, together with an inhibition of BCL-2. Moreover, MPOBA also suppressed the mRNA expression levels of SNAIL, EGFR, and N-cadherin and induced upregulation of E-cadherin, crucial genes related to the epithelial-to-mesenchymal transition (EMT). However, there was no significant difference in the IHC results of the expression patterns of vimentin (VT) and cytokeratin (CK) between MPOBA-treated and control CMC cells. In conclusion, the results of the present study suggested that MPOBA exhibited significant anticancer activity by inducing apoptosis in both CMCs via upregulation of TP53 and BAX and downregulation of BCL-2 relative mRNA expression. MPOBA may prove to be a potential candidate drug to be further investigated as a therapeutic agent for CMC. [ABSTRACT FROM AUTHOR]

Polymer anchored copper(II) complex of 2-acetylbenzimidazole was synthesized and characterized by elemental analysis, FT-IR, UV–Vis/DRS spectroscopy, magnetic moment, ESR, XPS, FE-SEM and thermogravimetric analysis. The catalytic activity of polymer supported [PS-CuCl2(ABIMZ)2] complex was investigated for oxidative esterification of different substituted aldehydes and alcohols using H2O2 as an oxidant. Influence of various factors, towards the formation of products, like effect of temperature, concentration of oxidant and concentration of catalyst were studied. PS-CuCl2(ABIMZ)2shows good catalytic activity and selectivity compared to unsupported CuCl2(ABIMZ)2 complex. Based on the results obtained, a tentative mechanism has been proposed. Under the optimized reaction conditions, the catalyst showed recycling ability up to five runs without any appreciable loss of its activity. [ABSTRACT FROM AUTHOR]

[Display omitted] Herein, new Bi 2 MoO 6 /Cs 3 Sb 2 Br 9 heterostructure (BiMo/CSB) was investigated for the first time as a visible-light-driven photocatalyst for C(sp3)–H bond activation using molecular oxygen as a green oxidant and toluene as a model substrate. The optimized BiMo/CSB photocatalyst exhibited enhanced toluene oxidation activity (2,346 μmol g-1h−1), which was almost two- and five-fold that of pristine CSB (1,165 μmol g-1h−1) and BiMo (482 μmol g-1h−1), respectively. The improved photocatalytic performance was essentially attributed to the formation of staggered band energy lineup in the BiMo/CSB hybrid, which promoted S-scheme charge transfer across the BiMo/CSB heterointerface as supported by ultraviolet photoelectron spectroscopy (UPS), density functional theoretical (DFT), time-resolve photoluminescence (TRPL), and photoelectrochemical studies. Spin–trapping electron paramagnetic resonance (EPR) and radical scavenging studies revealed that photoinduced hole, molecular oxygen, and superoxide radical are key active species in this photocatalytic system. The developed BiMo/CSB catalyst provided good selectivity toward benzaldehyde product (94–98 %), presumably due to the inhibiting effect of benzyl alcohol on benzaldehyde oxidation. No significant change in structure and morphology was observed for the spent catalyst, however small negative shift of Sb 3d and Bi 4f binding energy was found suggesting partial reduction of Sb3+ and Bi3+. This work not only provides a new visible-light-driven photocatalyst for C(sp3)–H bond activation but also opens the doors for exploitation of the conversion and functionalization of this inert bond toward the production of high value-added organic chemicals. [ABSTRACT FROM AUTHOR]

In order to fully utilize the by-products of apricot kernel-debitterizing and address the chemical instability of benzaldehyde in the food industry, benzaldehyde was first prepared by adding the apricot kernel powder to degrade the amygdalin present in the apricot kernel-debitterizing water. Subsequently, β-cyclodextrin was employed to encapsulate the benzaldehyde, and its encapsulation efficacy was evaluated through various techniques including Fourier transform infrared spectroscopy, thermogravimetric analysis, release kinetics fitting inhibitory effect and the effect on Botrytis cinerea. Finally, the encapsulation was explored via molecular docking and molecular dynamics simulations. The results indicate that the optimal preparation conditions for the benzaldehyde were 1.8 h, 53 °C and pH 5.8, and the encapsulation of benzaldehyde with β-cyclodextrin (wall–core ratio of 5:1, mL/g) has been verified by the deceleration in the release rate, the enhanced thermal stability and the prolonged inhibition effect against Botrytis cinerea. The encapsulation proceeded spontaneously without steric hindrance in the simulation, which led to a reduction in the hydrophobic cavity of β-cyclodextrin. In conclusion, the amygdalin in the debitterizing wastewater can be degraded in an eco-friendly way to produce benzaldehyde by adding apricot kernel powder, which contains β-glucosidase; the encapsulation of benzaldehyde is stable, thus enhancing the utilization of amygdalin in the debitterizing wastewater of apricot kernels. [ABSTRACT FROM AUTHOR]

A new alkaloid, 2-acetyl-4-methoxyfuro[2,3-b]quinoline (1), and a new benzaldehyde derivative, (2′S)-4-(2′-hydroxy-3′-methyl-3′-butenoxy)benzaldehyde (2), were isolated from the twig of Zanthoxylum rhetsa (Roxb.) DC. along with twenty-six known compounds (3−28). Their structures were determined by spectroscopic analysis (1D and 2D NMR spectroscopy and HRMS analysis) and comparison with data reported in the literature. Thirteen of the known compounds were evaluated for their cytotoxic activities against human cancer cell lines that included MDA-MB-231, SW1353, A549, and HCT116. (±)-8-Acetonyldihydronitidine (15) showed moderate cytotoxicity toward the SW1353 cancer cell line with an IC50 value of 18.90±0.39 µg/mL, and exhibited weak cytotoxic activity against MDA-MB-231, A549 and HCT116 cell lines with IC50 values of 49.86−71.32 µg/mL. [ABSTRACT FROM AUTHOR]

Globally, cancer is the leading cause of death and morbidity, and skin cancer is the most common cancer diagnosis. Skin problems can be treated with nanoparticles (NPs), particularly with zinc oxide (ZnO) NPs, which have antioxidant, antibacterial, anti‐inflammatory, and anticancer properties. An antibacterial activity of zinc oxide nanoparticles prepared in the presence of 4‐nitrobenzaldehyde (4NB) was also tested in the present study. In addition, the influence of synthesized NPs on cell apoptosis, cell viability, mitochondrial membrane potential (MMP), endogenous reactive oxygen species (ROS) production, apoptosis, and cell adhesion was also examined. The synthesized 4‐nitro benzaldehyde with ZnO (4NBZnO) NPs were confirmed via characterization techniques. 4NBZnO NPs showed superior antibacterial properties against the pathogens tested in antibacterial investigations. As a result of dose‐based treatment with 4NBZnO NPs, cell viability, and MMP activity of melanoma cells (SK‐MEL‐3) cells were suppressed. A dose‐dependent accumulation of ROS was observed in cells exposed to 4NBZnO NPs. As a result of exposure to 4NBZnO NPs in a dose‐dependent manner, viable cells declined and apoptotic cells increased. This indicates that apoptotic cell death was higher. The cell adhesion test revealed that 4NBZnO NPs reduced cell adhesion and may promote apoptosis of cancer cells because of enhanced ROS levels. [ABSTRACT FROM AUTHOR]

The one-pot three-component condensation of benzaldehyde, 1,3-indenedione, and indole was investigated at the B3LYP/6-311G level to explore the best reaction mechanism for the gas phase. All of routes were studied and structure of intermediates (IM) were optimized and all of respective transition states were found. Nine different mechanism paths were proposed and relevant calculations and investigations were performed. The calculation results proved that the proposed mechanism consists of three-step, enolic form of 1,3-indenedione, benzaldehyde and indole is more suitable than other mechanism routes. [ABSTRACT FROM AUTHOR]

Chalcone represents a vital biosynthetic scaffold owing to its numerous therapeutic effects. The present study was intended to synthesize 17 chalcone derivatives (3a–q) by direct coupling of substituted acetophenones and benzaldehyde. The target chalcones were characterized by spectroscopic analyses followed by their in vitro antimicrobial, and antileishmanial investigations with reference to standard drugs. The majority of the chalcones displayed good to excellent biological activities. Chalcone 3q (1000 µg ml−1) exhibited the most potent antibacterial effect with its zone of inhibition values of 30, 33 and 34 mm versus Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa respectively. The results also confirmed chalcone 3q to be the most potent versus Leishmania major with the lowest IC50 value of 0.59 ± 0.12 µg ml−1. Chalcone 3i (500 µg ml−1) was noticed to be the most potent antifungal agent with its zone of inhibition being 29 mm against Candida albicans. Computational studies of chalcones 3i and 3q supported the preliminary in vivo results. The existence of the amino moiety and bromine atom on ring-A and methoxy moieties on ring-B caused better biological effects of the chalcones. In brief, the investigations reveal that chalcones (3i and 3q) can be employed as building blocks to discover novel antimicrobial agents.

Abstract Background L-phenylalanine is an essential amino acid with various promising applications. The microbial pathway for L-phenylalanine synthesis from glucose in wild strains involves lengthy steps and stringent feedback regulation that limits the production yield. It is attractive to find other candidates, which could be used to establish a succinct and cost-effective pathway for L-phenylalanine production. Here, we developed an artificial bioconversion process to synthesize L-phenylalanine from inexpensive aromatic precursors (benzaldehyde or benzyl alcohol). In particular, this work opens the possibility of L-phenylalanine production from benzyl alcohol in a cofactor self-sufficient system without any addition of reductant. Results The engineered L-phenylalanine biosynthesis pathway comprises two modules: in the first module, aromatic precursors and glycine were converted into phenylpyruvate, the key precursor for L-phenylalanine. The highly active enzyme combination was natural threonine aldolase LtaEP.p and threonine dehydratase A8HB.t, which could produce phenylpyruvate in a titer of 4.3 g/L. Overexpression of gene ridA could further increase phenylpyruvate production by 16.3%, reaching up to 5 g/L. The second module catalyzed phenylpyruvate to L-phenylalanine, and the conversion rate of phenylpyruvate was up to 93% by co-expressing PheDH and FDHV120S. Then, the engineered E. coli containing these two modules could produce L-phenylalanine from benzaldehyde with a conversion rate of 69%. Finally, we expanded the aromatic precursors to produce L-phenylalanine from benzyl alcohol, and firstly constructed the cofactor self-sufficient biosynthetic pathway to synthesize L-phenylalanine without any additional reductant such as formate. Conclusion Systematical bioconversion processes have been designed and constructed, which could provide a potential bio-based strategy for the production of high-value L-phenylalanine from low-cost starting materials aromatic precursors.

Face masks are usually used to prevent inhalable particles and microdroplets that may enter the nose and mouth. However, a lot of organic contaminants can be found in materials, manufacturing processes, or packaging of face mask, so there is a potential health risk during mask-wearing for a long time. Benzaldehyde is one of the simple and common aromatic aldehydes with highly active chemical properties, which is one of the typical contaminants in face mask and is a high-risk volatile organic compound for human health. To understand the potential health risk of benzaldehyde during wearing a mask, it is of great significance to monitor the possible photochemical reaction of benzaldehyde during mask-wearing under the conditions of sunshine and ozone. Mass spectrometry has attracted extensive attention in monitoring chemical reactions under complex environmental conditions, because of its high sensitivity, excellent accuracy and fast signal response. Direct mass spectrometry can provide a powerful tool for sample analysis, which requires no or little sample pretreatment. In this study, the products of benzaldehyde under different treatment conditions were investigated by direct mass spectrometry with direct electrospray ionization on mask material, and were further verified by comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC-MS) that can provide a high-resolution separation and highly sensitive detection for complex volatile samples. Photochemical reaction and oxidation reaction mechanisms of benzaldehyde were also proposed. The results showed that many organic compounds such as benzophenone, 4-pentenoic acid, methyl benzoate, benzoic acid can be formed by benzaldehyde under exposure to ultraviolet (UV) light and ozone. This method can provide a new way to gain insight into contaminants of mask devices under different environmental conditions.

In this report, we developed an efficient one-pot method for the synthesis of 3-phenyl-1-(phenylthio)imidazo[1,5-a]pyridine analogs starting from 2-aminomethylpyridines, benzaldehydes, and sodium benzenesulfinates, which constructed C-N and C-S bonds simultaneously. The method features mild reaction conditions, a wide range of substrates, high atom utilization, and convenient and easily accessible starting materials.

The rise of antibiotic tolerance in bacteria harboring genetic elements conferring resistance to antibiotics poses an increasing threat to public health. However, the primary factors responsible for the emergence of antibiotic tolerance and the fundamental molecular mechanisms involved remain poorly comprehended. Here, we demonstrate that the commonly utilized food additive Benzaldehyde (BZH) possesses the capacity to induce a significant level of fluoroquinolone tolerance in vitro among resistant Escherichia coli. Our findings from animal models reveal that the pre-administration of BZH results in an ineffective eradication of bacteria through ciprofloxacin treatment, leading to similar survival rates and bacterial loads as observed in the control group. These results strongly indicate that BZH elicits in vivo tolerance. Mechanistic investigations reveal several key factors: BZH inhibits the formation of bacterial flagella and releases proton motive force (PMF), which aids in expelling antibiotics from within cells to reducing their accumulation inside. In addition, BZH suppresses bacterial respiration and inhibits the production of reactive oxygen species (ROS). Moreover, exogenous pyruvate successfully reverses BZH-induced tolerance and restores the effectiveness of antibiotics, highlighting how crucial the pyruvate cycle is in combating antibiotic tolerance. The present findings elucidate the underlying mechanisms of BZH-induced tolerance and highlight potential hazards associated with the utilization of BZH.

We report a strategy for achieving the selective detection of benzaldehyde and aniline by using Fischer's base (Cy237). The response of Cy237 to benzaldehyde and aniline yielded obvious color changes and a fluorescence redshift after 405 nm-wavelength LED light irradiation, and visual detection of benzaldehyde and aniline by the naked eye was realized. Furthermore, Cy237 was successfully applied for the discrimination of benzene series compounds in effluent and food. [ABSTRACT FROM AUTHOR]

Chiral β-amino alcohols are crucial building blocks in the synthesis of pharmaceutically active molecules and natural products. Developing green and sustainable methods for synthesizing chiral β-amino alcohols from renewable feedstocks continues to pose a significant challenge. Herein, we proposed a simple one-pot two-stage artificial cascade biocatalysis system for highly efficient conversion of renewable biomass-derived aldehydes into chiral β-amino alcohols with good yields and excellent enantioselectivity via sequential hydroxymethylation and asymmetric reduction amination. The initial stage involves converting aldehydes into α-hydroxy ketones by providing formaldehyde through benzaldehyde lyase-catalyzed hydroxymethylation. The subsequent stage is to convert α-hydroxy ketones into chiral β-amino alcohols through amine transaminase-catalyzed asymmetric reduction amination. Combining the two different types of reactions with two different enzymes, biomass-derived furfural 1a could be easily converted into (R)-2-amino-2-(furan-2-yl)ethanol ((R)-3a) and (S)-2-amino-2-(furan-2-yl)ethanol ((S)-3a) with up to 95% and 92% conversions and >99% ee, respectively. In addition, with this cascade biocatalysis, several enantiopure arylglycinols 3b–e were synthesized (39.4–99.0% conversions and >99% ee) from the biomass-derived benzaldehydes (1b–c) and benzaldehyde derivatives (1d–e). Furthermore, biotransformation on a preparative scale gave (S)-3a and (R)-3a in good yields (64.6% and 60.4%) and excellent ee (>99%). This study presents an eco-friendly and sustainable approach for synthesizing chiral β-amino alcohols using biomass-derived aldehydes. [ABSTRACT FROM AUTHOR]

The luminescence properties and excellent carrier transfer ability of carbon quantum dots (CQDs) have attracted much attention in the field of photocatalysis. In this work, we loaded the CQDs on the surface of Cu2O to enhance the visible-light property of Cu2O. Furthermore, the composite was used for selective oxidation of benzyl alcohol to benzaldehyde. The composite catalyst achieved high selectivity (90%) for benzaldehyde at room temperature, leveraging its visible-light-induced electron transfer properties and its photocatalytic activity for hydrogen peroxide decomposition. ·OH was shown to be the main reactive oxygen species in the selective oxidation reaction of benzyl alcohol. The formation of heterostructures of CQDs/Cu2O promoted charge carrier separation and provided a fast channel for photoinduced electron transfer. This novel material exhibited enhanced levels of activity and stability for selective oxidation of benzyl alcohol. Potential applications of carbon quantum dot composites in conventional alcohol oxidation reactions are shown. [ABSTRACT FROM AUTHOR]

The synergistic of organic transformation with H 2 production in one redox cycle is highly desirable to achieve the full use of photogenerated holes and electrons but challenging. Herein, Lewis acid-base nanocatalysts in which Ni decorated defective ZnIn 2 S 4 (denoted as Ni/VZIS) has been prepared through photodeposition with Zn defective ZnIn 2 S 4 nanosheets as precursor. The Zn vacancies favors the selective deposition of Ni, enabling the co-exposure of Lewis acid Ni and Lewis base S adjacent dual active sites. In-situ FTIR results reveal the coexistence of Ni and Zn vacancy on ZnIn 2 S 4 favored the chemisorption of benzyl alcohol. The electron-deficient Ni Lewis acid (LA) site and electron-rich S Lewis base (LB) site can act as benzyl alcohol conversion and H 2 evolution sites, respectively, thus facilitating the full use of photoinduced electrons and holes. The spectroscopy and photoelectrochemical studies demonstrate the transfer and separation of photogenerated carries are also facilitated in the nanohybrids. As such, the Ni/VZIS photocatalyst show outstanding performance of photocatalytic conversion benzyl alcohol (BA) into benzaldehyde (BAD) and H 2 , with the optimal H 2 generation rate of 81.9 μmol h−1, accompanying benzaldehyde generation rate of 73.7 μmol h−1. This work provides a profound insight into the designing of multi-functionalized nanohybrids for the full use of photoexcited electrons-holes pairs. [Display omitted] • Ni modified ZnIn 2 S 4 with Zn vacancies catalysts are successfully fabricated. • LA Ni site and Zn vacancy favored the chemisorption of benzyl alcohol. • The electron-rich S Lewis base site are efficient H 2 evolution sites. • High-performance of the Lewis acid-base nanocatalyst is achieved. [ABSTRACT FROM AUTHOR]

Background: L-phenylalanine is an essential amino acid with various promising applications. The microbial pathway for L-phenylalanine synthesis from glucose in wild strains involves lengthy steps and stringent feedback regulation that limits the production yield. It is attractive to find other candidates, which could be used to establish a succinct and cost-effective pathway for L-phenylalanine production. Here, we developed an artificial bioconversion process to synthesize L-phenylalanine from inexpensive aromatic precursors (benzaldehyde or benzyl alcohol). In particular, this work opens the possibility of L-phenylalanine production from benzyl alcohol in a cofactor self-sufficient system without any addition of reductant. Results: The engineered L-phenylalanine biosynthesis pathway comprises two modules: in the first module, aromatic precursors and glycine were converted into phenylpyruvate, the key precursor for L-phenylalanine. The highly active enzyme combination was natural threonine aldolase LtaEP.p and threonine dehydratase A8HB.t, which could produce phenylpyruvate in a titer of 4.3 g/L. Overexpression of gene ridA could further increase phenylpyruvate production by 16.3%, reaching up to 5 g/L. The second module catalyzed phenylpyruvate to L-phenylalanine, and the conversion rate of phenylpyruvate was up to 93% by co-expressing PheDH and FDHV120S. Then, the engineered E. coli containing these two modules could produce L-phenylalanine from benzaldehyde with a conversion rate of 69%. Finally, we expanded the aromatic precursors to produce L-phenylalanine from benzyl alcohol, and firstly constructed the cofactor self-sufficient biosynthetic pathway to synthesize L-phenylalanine without any additional reductant such as formate. Conclusion: Systematical bioconversion processes have been designed and constructed, which could provide a potential bio-based strategy for the production of high-value L-phenylalanine from low-cost starting materials aromatic precursors. [ABSTRACT FROM AUTHOR]

Face masks are usually used to prevent inhalable particles and microdroplets that may enter the nose and mouth. However, a lot of organic contaminants can be found in materials, manufacturing processes, or packaging of face mask, so there is a potential health risk during mask-wearing for a long time. Benzaldehyde is one of the simple and common aromatic aldehydes with highly active chemical properties, which is one of the typical contaminants in face mask and is a high-risk volatile organic compound for human health. To understand the potential health risk of benzaldehyde during wearing a mask, it is of great significance to monitor the possible photochemical reaction of benzaldehyde during mask-wearing under the conditions of sunshine and ozone. Mass spectrometry has attracted extensive attention in monitoring chemical reactions under complex environmental conditions, because of its high sensitivity, excellent accuracy and fast signal response. Direct mass spectrometry can provide a powerful tool for sample analysis, which requires no or little sample pretreatment. In this study, the products of benzaldehyde under different treatment conditions were investigated by direct mass spectrometry with direct electrospray ionization on mask material, and were further verified by comprehensive two-dimensional gas chromatography-mass spectrometry (GC×GC-MS) that can provide a high-resolution separation and highly sensitive detection for complex volatile samples. Photochemical reaction and oxidation reaction mechanisms of benzaldehyde were also proposed. The results showed that many organic compounds such as benzophenone, 4-pentenoic acid, methyl benzoate, benzoic acid can be formed by benzaldehyde under exposure to ultraviolet (UV) light and ozone. This method can provide a new way to gain insight into contaminants of mask devices under different environmental conditions. [ABSTRACT FROM AUTHOR]

Oxindoles are prevalent structures in natural products and pharmaceutically active molecules. To support structure–activity‐relationship (SAR) studies in a medicinal chemistry program, we developed a straightforward and scalable synthesis route to 1‐aminoethyl oxindole building blocks harboring various types of substituents. Our strategy relies on an intramolecular Buchwald–Hartwig amidation of a 2‐bromophenylacetic amide precursor. The cyclization substrates can be prepared from readily available benzaldehydes by ortho‐selective C(sp2)−H bromination followed by homologation to the corresponding phenylacetic acid derivatives. The process was optimized to allow for preparation of 246 g of one representative example. [ABSTRACT FROM AUTHOR]

The synthesis of benzaldehyde, a compound widely utilized in food, medicine, and cosmetics, was achieved through a one-step catalytic hydrogenation using the cost-effective raw material, methyl benzoate. This process aligns with the principles of atom economy and green production. Despite the development of numerous high-performance catalysts by scholars, the challenge remains in achieving lower reaction temperatures, ideally below 400 °C. In this study, a series of MnOx/γ-Al2O3 catalysts were meticulously prepared using the precipitation-impregnation method. These catalysts featured supports calcined at various temperatures and distinct manganese active components. Characterization techniques such as X-ray diffraction (XRD), N2 physical adsorption, Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), H2 temperature programmed reduction (H2-TPR), and NH3 temperature-programmed desorption (NH3-TPD) were employed to analyze the structure and surface properties of the catalysts. Notably, the optimized reaction temperature was found to be 360 °C. The catalyst exhibited the most favorable performance when the calcination temperature of the support was 500 °C and the Mn/Al molar ratio reached 0.18. Under these conditions, the catalyst demonstrated the most suitable oxygen vacancy concentration, yielding impressive results: a conversion rate of 87.90% and a benzaldehyde selectivity of 86.1%. These achievements were attained at 360 °C, atmospheric pressure, a hydrogen to methyl benzoate molar ratio of 40:1, and a Gas Hourly Space Velocity (GHSV) of 800 h−1. This research underscores the potential for optimizing catalysts to enhance the efficiency and sustainability of benzaldehyde synthesis. [ABSTRACT FROM AUTHOR]

Tungstoborate heteropolyacid catalysts have good catalytic degradation performance, especially for selective cleavage of C–C bonds in biomass. In this paper, the product yield and component distribution of tungstoborate heteropolyacid (BW12)-catalyzed lignin liquefaction were investigated at different parameters, including temperatures (120, 140, 160, 180, and 200 °C), catalyst amount (0, 2.5, 5, 10, and 20 wt. %), and reaction time (0, 30, 60, 90, and 120 min). It was found that a higher conversion (72.16 wt. %) and bio-oil yield (68.41 wt. %) could be obtained under suitable reaction conditions (180 °C, 60 min, 5 wt. %). Bio-oil analysis showed that the BW12 catalyst had a significant effect on the distribution of bio-oil fractions, in which mono-aromatic components increased from 32.96% to 47.56% compared to those without the catalyst. In particular, carbonyl substances in the mono-aromatic components increased from 18.66% to 26.97%. Spectroscopic analysis (FT-IR) found that the absorption peaks of C–O and C–C bonds in the liquefied residue catalyzed by BW12 decreased compared to the raw lignin. Moreover, the mechanism of BW12-catalyzed lignin depolymerization was investigated by DFT simulations. The simulation results demonstrated that the shortening of Cα–O bond, the breaking of Cβ–Cγ and Cα–Cβ bonds in lignin promoted the formation of vanillin and benzaldehyde, 3-hydroxy-4-methoxy. Finally, based on the experimental data and simulation results, a possible reaction pathway for the BW12-catalyzed liquefaction of lignin into mono-aromatic substances was proposed. [ABSTRACT FROM AUTHOR]

This article reports, the fabrication of cationic microgel doped MnO2/Fe3O4 nanocomposites (CM@MnO2/Fe3O4) via free radical emulsion polymerization technique, and an economical and environmental friendly approach to some organic transformations, such as heterogeneous photocatalytic reduction of methylene blue (MB, toxic dye), para‐nitro phenol (PNP, harmful pollutant) and dimethyl amino benzaldehyde (DMAB, skin allergic reagent) in presence of UV light (38 W). First of all, three different crosslinked grades of cationic microgels (CMs) have been synthesized by using styrene, dimethyl acrylamide, cyclohexyl methacrylate, [2‐(acryloyloxy)ethyl] trimethylammonium chloride and N‐hydroxymethyl acrylamide monomers by taking different amounts of N‐hydroxymethyl acrylamide, and keeping the other monomers in fixed quantities. Further, all the grades of CMs have been doped by bimetallic MnO2/Fe3O4 nanoparticles, through hydrothermal method. Fabrication of CMs and CM@MnO2/Fe3O4 nanocomposites has been confirmed by the characteristic peaks observed in FT‐IR spectral analysis and their thermal stability has been evidenced by thermogravimetric analysis. TEM and DLS analyses have revealed their particular size. The surface morphology of CMs and CM@MnO2/Fe3O4 nanocomposites has been visualized by scanning electrode microscope analysis. The nanocomposites have effectively and efficiently catalyzed the reduction reactions of MB, PNP, and DMAB, in presence of UV light, by 98%, 98%, and 86%, respectively. The photocatalysts have been reused up to eight cycles without any loss of their catalytic activity. The photocatalytic reductions have also been studied for their kinetics, and exhibited pseudo first order kinetics (kapp, 10−2 min−1). [ABSTRACT FROM AUTHOR]

Ponstane Fort, a famous pharmaceutical drug has many medicinal uses. Recently, it has been used in different chemical reactions in order to improve its biological effectiveness. Three chemical compounds have been prepared as derivatives of Mefenamic acid by certain steps included adding thiosemicarbazide to Mefenamic acid with a catalyst of H2SO4 to obtain a Mefenamic derivative C1; mixing a certain amount of C1 with 4- carboxybenzaldehyde to obtain compound C2; dissolving C2 at various reagents by diazotization reaction to yield Mefenamic derivative C3. All formatted compounds had been monitored through FTIR-Spectra, 1H.NMRSpectra, Mass-Spectra and melting point. This method has high target product productivity, simple process procedures, mild reaction conditions, simple purifying process, high product purity and suitability for industrialized production. So that the production cost is further reduced. By using the agar well diffusion method, all prepared three compounds showed good antibacterial activity against studied Gram-positive and Gramnegative bacteria, however, C3 showed the highest activity. A skin test for Delayed Hypersensitivity was done to know if there are allergic reactions for the created compounds, while the test for Killing Mice has been done for testing mortality rate in animals. The compounds have a high cellular immune response through in experimental animals. [ABSTRACT FROM AUTHOR]

Several regulations on exhaust gases have been introduced to curb hazardous exhaust of volatile organic compounds (VOCs) and particulate matter (PM) from the paint and printing industries. VOCs produce photochemical oxidants and suspended PM such as PM2.5, which is now recognized as a global environmental problem. We assess a nonthermal plasma technique for controlling VOC emissions, especially, propose a wet-type packed-bed plasma reactor to extend the treatment of water-non-soluble VOCs. This paper proposes a wet-type packed-bed plasma reactor to extend the treatment of water-non-soluble VOCs. The proposed technique is evaluated through the simultaneous removal of nanoparticles and toluene at a relatively high flow rate. Simultaneous treatment of the VOCs and nanoparticles using the reactor indicates that the average particle collection efficiency is 94%, and the removal efficiency of 60 ppm toluene is 73% with a gas flow rate of 10 L/min. The resultant byproducts are benzaldehyde (C6H5CHO), benzyl alcohol (C6H5CH2OH), phenol (C6H5OH), ozone, formic acid, and acetic acid, and some are easily dissolved and removed by the sodium hydroxide solution film. A smaller pellet diameter leads to more efficient toluene removal at lower specific energy values, while the ozone concentration does not change. However, the ozone concentration can be greatly suppressed by dissolving the ozone in the alkali solution film. [ABSTRACT FROM AUTHOR]

A modular platform for facile access to 1,2,3,9‐tetrahydro‐4H‐carbazol‐4‐ones (H4‐carbazolones) and 3,4‐dihydrocyclopenta[b]indol‐1(2H)‐ones (H2‐indolones) is described. The requisite 6‐ and 5‐membered 2‐arylcycloalkane‐1,3‐dione precursors were readily obtained through a Cu‐catalyzed arylation of 1,3‐cyclohexanediones or by a ring expansion of aryl succinoin derivatives. Enolization of one carbonyl group in the diones, conversion to a leaving group, and subsequent azidation gave 2‐aryl‐3‐azidocycloalk‐2‐en‐1‐ones. This two‐step, one‐pot azidation is highly regioselective with unsymmetrically substituted 2‐arylcyclohexane‐1,3‐diones. The regioselectivity, which is important for access to single isomers of 3,3‐disubstituted carbazolones, was analyzed mechanistically and computationally. Finally, a Rh‐catalyzed nitrene/nitrenoid insertion into the ortho C−H bond of the aryl moiety gave the H4‐carbazolones and H2‐indolones. One carbazolone was elaborated to an intermediate reported in the total synthesis of N‐decarbomethoxychanofruticosinate, (−)‐aspidospermidine, (+)‐kopsihainanine A. With 2‐phenylcycloheptane‐1,3‐dione, prepared from cyclohexanone and benzaldehyde, the azidation reaction was readily accomplished. However, the Rh‐catalyzed reaction unexpectedly led to a labile but characterizable azirine rather than the indole derivative. Computations were performed to understand the differences in reactivities of the 5‐ and 6‐membered 2‐aryl‐3‐azidocycloalk‐2‐en‐1‐ones in comparison to the 7‐membered analogue, and to support the structural assignment of the azirine. [ABSTRACT FROM AUTHOR]

The presence of syn and anti-conformers in tetramethyl substituted meta-benziporphodimethenes has been well studied. Herein, we report a new sterically hindered hexaaryl-m-benziporphodimethene (m-BPDM) using benzaldehyde and its Zn(II) and Cd(II) complexes. The UV-Vis, mass, and NMR characterized data confirmed the synthesis of these m-BPDM analogues. Time-dependent DFT analysis has been performed to visualize the distribution of electron density at the HUMO and LUMO. The present work primarily focuses on the comparative study of the syn,anti-conformers of metallated meta-benziporphodimethenes upon increasing the bulkiness at the sp3meso carbon atoms. The placement of –H, –CH3, and –Ph groups at the C6- and C21-positions of m-BPDM greatly impacts the stability of these conformers, which has been explored. Along with this, a comparison has also been drawn between the reported X-ray crystallographic geometry and B3LYP/LANL2DZ optimized structures for free-base tetramethyl-m-BPDM and its Zn(II) and Cd(II) complexes. The article sums up the much-anticipated results from the tetramethylene analogue of m-BPDM, which were contrary to that of tetraphenylene analogues. [ABSTRACT FROM AUTHOR]

In this work, two ZIF-8-based biocomposites were obtained by entrapping the biomolecules benzaldehyde and methyl anthranilate via direct impregnation with fast encapsulation kinetics and high molecule payloads were achieved. The obtained biocomposites exhibit an enhanced antifungal activity against Penicilium expansum after integration in biopolymeric zein films in comparison with the action of free molecules, making these biomaterials promising candidates for food preservation and packaging applications. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis of halogen-bond-donor-site-introduced functional monomers through the Wittig reaction of perfluorohalogenated benzaldehydes. The study focuses on the potential utility of perfluorohalogenated styrenes as functional monomers in smart polymer materials. The authors report on the Wittig reaction of perfluorohalogenated benzaldehydes and provide insights into the key factors for obtaining these functional monomers. The research aims to facilitate future research endeavors in the field of small-molecule synthesis. The given text appears to be a table showing various reactions and their conditions. It also includes information about molecular electrostatic potential maps, V s,min, and NBO charges. The table provides data on different organic bases and their corresponding values for V s,min and NBO charges. The information seems to be relevant for research on organic chemistry and may be useful for understanding the properties and behavior of different organic bases. This article discusses the development of an organic-base-mediated Wittig reaction for the synthesis of 2,3,5,6-tetrafluoro-4-halobenzaldehydes (TFXSs) from 2,3,5,6-tetrafluoro-4-halobenzaldehydes. The authors conducted experiments using different bases and solvents to optimize the reaction conditions and improve the yield of TFXSs. They also performed density functional theory (DFT) calculations [Extracted from the article]

Four new natural compounds named hericenone O (1), hericenone P (2), hericenone Q (3), and hericenone R (4), two of them were reported synthetically (3-4), together with eleven known compounds were isolated from the fruiting bodies of Hericium erinaceus. The chemical structures of the isolated compounds were elucidated by using NMR analysis and mass spectrometry, as well as comparisons with the reported data in the literature. The bioactivity evaluation revealed that hericenone Q showed significant cytotoxic activity against Hep-G2 with IC50 values of 23.89 μM, and against HCT-116 with IC50 values of 65.64 μM. [ABSTRACT FROM AUTHOR]

In this study, we have reported the impact of the surface morphologies and distinct exposed facets of WO3 nanoparticles on the photocatalytic oxidation of toluene. We successfully synthesized monoclinic-WO3 nanocubes (WNCs), hexagonal-WO3 nanosheets (WNSs), and nanorods (WNRs) with dominant exposed facets of (200), (110), and (110), respectively. The structural properties of the materials were thoroughly scrutinized using various analytical techniques, including X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET), UV–vis, and X-ray photoelectron spectroscopy (XPS). The formation energies of the oxygen vacancy surfaces of WO3(100) and WO3(110) planes and the binding energy of reactant molecules, including O2 and toluene, were calculated using plane wave density functional theory (DFT). The WO3(100) surface is more active for the adsorption of O2 (adsorption energy −8.8 eV) than the (110) surface (adsorption energy −4.4 eV) on the oxygen vacancy site. Toluene adsorption on the (100) surface is also found to be more favorable by 1.01 eV compared to that on the (110) surface. Overall, WNC(100) was more active for the oxidation of toluene to benzaldehyde than WNS(110) and WNR(110), which is in good agreement with the experimental results. WNCs demonstrated exceptional photocatalytic performance with a benzaldehyde formation rate of 650 mmol g–1 h–1. Additionally, it exhibited a high benzaldehyde selectivity (99%) and remarkable stability. [ABSTRACT FROM AUTHOR]

Photocatalytic organic functionalization reactions represent a green, cost‐effective, and sustainable synthesis route for value‐added chemicals. However, heterogeneous photocatalysis is inefficient in directly activating ammonia molecules for the production of high‐value‐added nitrogenous organic products when compared with oxygen activation in the formation of related oxygenated compounds. In this study, we report the heterogeneous photosynthesis of benzonitriles by the ammoxidation of benzyl alcohols (99 % conversion, 93 % selectivity) promoted using BiOBr nanosheets with surface vacancy associates. In contrast, the main reaction of catalysts with other types of vacancy sites is the oxidation of benzyl alcohol to benzaldehyde or benzoic acid. Experimental measurements and theoretical calculations have demonstrated a specificity of vacancy type with respect to product selectivity, which arises from the adsorption and activation of NH3 and O2 that is required to promote subsequent C−N coupling and oxidation to nitrile. This study provides a better understanding of the role of vacancies as catalytic sites in heterogeneous photocatalysis. [ABSTRACT FROM AUTHOR]

The article represents a translated, revised, and updated Section 6.3 of the monograph by A.S. Burlov, V.G. Vlasenko, D.A. Garnovskiy, A.I. Uraev, E.I. Maltsev, D.A. Lypenko, and A.V. Vannikov, Electroluminescent Organic Light-Emitting Diodes Based on Metal Coordination Compounds, Rostov-on-Don: Yuzhn. Fed. Univ., 2015; ISBN 978-5-9275-1469-4 (see Additional Information). This section is dedicated to reviewing the photoluminescence and electroluminescence properties of metal complexes based on bi- and polydentate ligands of the azomethine type (Schiff bases). Many metal complexes of Schiff bases find wide use as luminescent materials. One of the applications of these compounds is the use as emissive layers or dopants for manufacturing OLED. The photo- and electroluminescence properties of a series of the metal complexes with the ligands based on the derivatives of hydroxybenzaldehyde, 2-(N-tosylamino)benzaldehyde, 1‑phenyl-3-methyl-4-formylpyrazol-5-one, and some others are reviewed. The systematic categorization of these compounds extends beyond their photophysical properties to consider the electroluminescence characteristics observed in OLED devices employing them as the basis. By modifying known azomethine-type ligand systems, one can obtain metal complex compounds with exceptional thermal stability, solubility, and quantum efficiency. These characteristics enable their use as luminescent materials in highly efficient OLED devices. [ABSTRACT FROM AUTHOR]

Synthesized substituted N-acetyl-3,5-diaryl-2-pyrazolines through their chalcone intermediates and evaluated for anti-cancer activity. Chalcones were synthesized from 2,4,5-trimethoxy benzaldehyde obtained from oxidation of β-asarone ((Z)-2,4,5-trimethoxy-1-propenylbenzene) is a major active principle component found in Acorus calamus oil (70–80%) and reacting with substituted acetophenones by Claisen-Schmidt condensation. Substituted chalcones were further treated with hydroxylamine in presence of sodium acetate and acetic acid cyclizes to give directly the corresponding N-acetyl-3,5-diaryl-2-pyrazolines in 68–85% yields. Structures were confirmed by IR, GC-MS,1H NMR, and 13C NMR.These novel analogues were evaluated for their in vitro anticancer activity against three human tumor cell lines (MCF-7, SW-982, and HeLa) using MTT assay. The results reveled that among the synthesized pyrazolines, which are having electron donor groups in para position of the aryl ring, i.e. 5th position of the N-acetyl pyrazolines showed better inhibitory activity (5b, 5c, 5d, 5e, 5f, 5g, 5k, and 5j) when compared with β-asarone. The compound 3'-nitro, 4'-chloro pyrazolines (5k) showed highest IC50 values 11.67 ± 0.54, 14.17 ± 0.92, and 18.26 ± 0.98 µg/mL (P <0.05) respectively, when compared to natural precursor. [ABSTRACT FROM AUTHOR]

A comparative study of a Schiff base reaction involving benzaldehyde and n-butylamine was carried out to improve the yield of the resulting imine. This reaction was carried out at different temperatures without and with the elimination of the water produced during the process by the pervaporation (PV) technique using a typical cylindrical cell. To reach this goal, different dense membranes made of crosslinked poly(vinyl alcohol) with different oxalic acid (crosslinker) contents were prepared by the solvent casting method. Different parameters influencing the performance of the membrane in the separation process including swellability, diffusivity, crosslinking density, and thermal properties were investigated. The total and partial cumulative transmembranar fluxes as well as the separation factor were studied and the separation process was monitored by HPLC analysis. The n-butyl-1-phenylmethanimine produced was characterized by FTIR and 1HNMR analyses. The results obtained were a clear improvement in the yield of the reaction. For example, the yield obtained from the Schiff base reaction occurring without assistance by PV varied from 58 to 84 wt% when the temperature changed from 5 to 45 °C. On the other hand, when the PV process was used to eliminate water from this reaction mixture, the yield went from 90.4 to 98.6% by weight in this same temperature order. The cumulative total and partial fluxes significantly decreased with time. On the other hand, the separation factor reached a maximum at about one hour at 5, 15, and 45 °C. At 25 °C, the maximum total flux was reached at about 2 h of the PV process. The best selectivity of the PVA-0.5 membrane with regard to water was obtained at 15 °C. It was also revealed from the results obtained that the cumulative total and partial flux decreased rapidly with time and the separation factor reached a maximum at one hour into the PV process, in which 1.51 × 104 was reached at 15 °C, 6.25 × 103 and 3.50 × 103 at one hour of the separation process, and 10.23 × 103 at 25 °C at 2 h of the water removal by PV. [ABSTRACT FROM AUTHOR]

This work presents the synthesis of a new compound, 1-[aryl-(diphenylphosphono)methyl]-3,4,6-trimethylglycolurils, via the interaction of benzaldehyde and its mononitro- and monohydroxyderivatives with 1,3,4-trimethylglycoluril and triphenylphosphite. By varying the reaction conditions and the catalysts, the obtained product yields ranged from satisfactory to good. The diastereomers formed during the reaction were separated by semipreparative HPLC on the C18 stationary phase. The isolated diastereomers were characterized by 1H, 13C, and 31P NMR, and the structures of the diastereomers were confirmed using a single-crystal X-ray crystal structure analysis and quantum chemical calculations. [ABSTRACT FROM AUTHOR]

A novel double shelled titanium dioxide@mesoporous organosilica nanotubes as an amphiphilic photoactive nanoreactor for photocatalytic oxidation of styrene under green conditions. [Display omitted] In this work, we have proposed a strategy to fabricate double-shell nanotubes as amphiphilic photoactive nanoreactors (HTTBPC) through the ordered hybridization of mesoporous organosilicon (PMO) and titanium dioxide (TiO 2) nanotubes. Unlike the previous rough composite, the heterogeneous structure established between cobalt-porphyrin functionalized PMO and conventional TiO 2 has a staggered matching band gap, which makes it have excellent light harvesting and high carrier separation ability. This is still unexplored. Interestingly, the prepared photocatalysts exhibited superior activity (99%) and benzaldehyde selectivity (94%) in the oxidation of styrene in water at room temperature, which was 3.8 and 2.8 times higher than that of TiO 2 nanotubes and PMO functionalized with cobalt porphyrin, respectively. It was demonstrated that the strong interaction between cobalt porphyrin PMO and TiO 2 improved the separation of photogenerated carriers and the amphiphilic properties of mesoporous organosilica boosted the adsorption of substrate molecules in water, contributing to the significantly enhanced photocatalytic activity. This work provides a design of high-performance photocatalysts for alkene oxidation under green conditions. [ABSTRACT FROM AUTHOR]

The production of trifluoromethyl groups on organic compounds by graphene-based photocatalysts is an emerging research area in the 21st century. However, the pricey and poisonous nature of metal-based photocatalysts poses a significant barrier to the insertion of trifluoromethyl groups. Therefore, the trifluoromethylation of organic compounds and conversion into sustainable, greener chemicals via solar light irradiation is a hot and challenging topic. So, herein we developed a solar light-harvesting nitrogen enrich Eosin-Y functionalized graphene-based (NDGFE-Y) photocatalytic system with appropriate band gap and supported by UV-Visible, FTIR, XRD, and FE-SEM, Raman spectra and TGA curve. This prepared photocatalyst is a yardstick example for the photoinduced oxide CF3SO2Na to produce the CF3 as an electrophilic radical, effectively making the trifluoromethylation of benzaldehyde and their derivatives. The graphical abstract represents the highly selective NDGFE-Y photocatalyst for trifluoromethylation of Benzaldehyde under solar light irradiation. The NDGFE-Y photocatalyst has effective photocatalytic properties due to the functionalization of Eosin -Y dye. [ABSTRACT FROM AUTHOR]

Multicomponent reactions involving three or more reactants are commonly used to prepare dihydropyrimidinone with various bioactivities. This study reports the different routes for the synthesis of benzaldehyde-based dihydropyrimidinone via the Biginelli reaction and investigates the yield of the obtained products. The synthesis was performed via routes A, B, C, D, and E based on the formation of iminium, enamine, and Knoevenagel intermediates between urea, benzaldehyde, and ethyl acetoacetate. Route A, through a one-pot reaction via iminium, produced dihydropyrimidinone with a yield of 58%. The product from route B via iminium was obtained in 62% yield. Route C and D occurred via enamine at room temperature, and reflux gave the product 31% and 40% yield, respectively. Route E involving Knoevenagel intermediate provided the product in a 38% yield. ¹H NMR, FTIR, and MS spectroscopic techniques were used for structure elucidation. [ABSTRACT FROM AUTHOR]

A new organic‐inorganic hybrid open‐framework molybdovanadate with mixed‐valences of vanadium (V4+/V5+=4/3) and molybdenum (Mo5+/Mo6+=8/2) cations has been synthesized. The complex possesses the unique V/Mo ratio (7/10), fascinating 8‐C topological network and 1D 4‐MR channels (7.793 Å×6.699 Å). Importantly, its catalytic activities for the selective oxidation of benzyl alcohol to benzaldehyde (oxidant: H2O2, 30 wt %) have been well evaluated. The results indicated that it exhibited improved catalytic activities (conv.: 96.8 %) compared with the catalyst (Cpyr)5PV2Mo5W5O40 [conv.: 88.51 %, Cpyr=(C16H32C5H4N)+)], high recyclability and structural stability. Moreover, the conversions and selectivities (conv.: 82.4–92.5 %; sele.: 91.5–95.7 %) of the substrates containing electron donating groups (−OH, −CH3, −OCH3 and −Cl) were significantly higher than those of the substrate containing electron withdrawing group (−NO2) (conv. 67.4 %; sele.: 80.8 %). This is due to the fact that the −NO2 with a large Hammett substituent constant is not conducive to the generation of transition state products. The studies revealed the complex could act as a highly efficient heterogeneous catalyst in selective oxidation of benzyl alcohols. [ABSTRACT FROM AUTHOR]

The direct oxidative esterification of benzaldehydes and benzyl alcohols to high value-added aromatic esters under mild and green reaction conditions is significant in the fine chemical industry. The accurate design of catalysts with high catalytic performance is crucial for this process. Herein, 2,4,6-trimethylpyridine, benzoic anhydride, and terephthalaldehyde were used to prepare a covalent organic framework (COF) material, which was then used as a template to construct a mesoporous CeO2-supported Au nanoparticles catalyst. The obtained Au@CeO2 catalyst was thoroughly characterized, and it possessed a mesoporous structure with a high surface area. Meanwhile, the as-prepared Au@CeO2 exhibited excellent catalytic performance in the oxidative esterification of benzaldehydes and benzyl alcohols with methanol, affording the corresponding aromatic esters under mild and green reaction conditions. Furthermore, the Au@CeO2 catalyst could also be recycled. Therefore, this study provides a green and sustainable pathway for the synthesis of high-value-added esters through a direct oxidative esterification strategy. [ABSTRACT FROM AUTHOR]

The synthesis of N‐pyridinylamides has been realized by particularly efficient technologies via bimetallic organic (Co/Fe‐MOF) catalyzed oxidative amidation between 2‐aminopyridine and benzaldehyde. The C−N bond was formed with the presence of a catalyst (Co/Fe‐MOF) as a Lewis acid and the oxidant as DTBP. The oxidative amidation reaction was conducted in 1,4‐dioxane at 120 °C with a wide range of substrates producing the corresponding amide products in good to 94 % yields. Experimental results illustrated that This accessibly offers a significant improvement over the earlier successful attempts in forming N‐pyridinyl amides. The Co/Fe‐MOF material was synthesized by solvothermal methods with the salt mixture of Fe(NO3)3.9H2O and Co(NO3)2.6H2O. The material was determined by modern analytic methods like X‐ray diffraction (XRD), Fourier‐transform Infrared spectroscopy (FT‐IR), Scanning Electron Microscope (SEM), and N2 adsorption/desorption isotherms. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) organic transformations occurring at anodes are a promising strategy for circumventing the sluggish kinetics of the oxygen evolution reaction. Here, we report a free radical-mediated reaction instead of direct hole transfer occurring at the solid/liquid interface for PEC oxidation of benzyl alcohol (BA) to benzaldehyde (BAD) with high selectivity. A bismuth vanadate (BiVO4) photoanode coated with a 2,20-bipyridine-based covalent organic framework bearing single Ni sites (Ni-TpBpy) was developed to drive the transformation. Experimental studies reveal that the reaction at the Ni-TpBpy/BiVO4 photoanode followed first-order reaction kinetics, boosting the formation of surface-bound ·OH radicals, which suppressed further BAD oxidation and provided a nearly 100% selectivity and a rate of 80.63 µmol hour-1 for the BA-to-BAD conversion. Because alcohol-to-aldehyde conversions are involved in the valorizations of biomass and plastics, this work is expected to open distinct avenues for producing key intermediates of great value. [ABSTRACT FROM AUTHOR]

2H−MoS2 is an appealing semiconductor because of its Earth‐abundant nature, cheapness, and low toxicity. This material has shown promising catalytic activity for various energy‐related processes, but its use in catalysis for C−C bond forming reactions towards useful organic compounds is still largely unexplored. The lack of examples in organic synthesis is mainly due to the intrinsic difficulties of using bulk 2H−MoS2 (e. g., low surface area), which implies the reliance on high catalytic loadings for obtaining acceptable yields. This makes the optimization process more expensive and tedious. Here, we report the development of a 2H−MoS2‐mediated synthesis of valuable bis(indolyl)methane derivatives, using indoles and benzaldehydes as starting materials. Exploiting the Design of Experiments (DoE) method, we identified the critical parameters affecting the catalytic performance of commercial 2H−MoS2 powder and optimized the reaction conditions. Lastly, we demonstrated that the catalytic system has versatility and good tolerance towards functional group variations of the reagents. [ABSTRACT FROM AUTHOR]