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The C–H functionalization strategy was first applied to the Cu-mediated radical arylation reactions of triazolotriazines with aromatic diazonium salts. A series of C(3)-modified triazolo[5,1- c ][1,2,4]triazines were obtained in yields of up to 80% under mild conditions. The radical nature of the reaction mechanism was established by the TEMPO radical trap experiments. The developed method is characterized by its versatile application opportunities, particularly it allows C(3)-arylated azoloazine-derived compounds of various architectures to be available. The elaborated synthetic strategy is of interest in the directed design of azaheterocyclic biomolecules with diverse pharmacological applications. [ABSTRACT FROM AUTHOR]

Despite the widespread applications of aryl diazonium salts, capturing both aryl radicals and aryl diazo radicals simultaneously remains a significant challenge due to the extreme instability of the diazonium radicals. Herein, we report a mild and efficient electrochemical reduction approach employing aryl diazonium salts as dual synthons to synthesize valuable multi-substituted pyrazoles for the first time. Furthermore, this method demonstrates significant practical potential through the modification of pharmaceutical intermediates, and a two-step one-pot approach that utilizes anilines as starting materials. [ABSTRACT FROM AUTHOR]

The article discusses the synthesis of aryl iodides and azides from aryl amines using copper phthalocyanine tetrasulfonic acid as a solid acid catalyst. The method offers advantages such as regiospecific iodination, mild reaction conditions, and the use of water as a solvent. The results show high yields and the ability to recycle the catalyst multiple times without significant loss of activity. The study provides a detailed experimental procedure and characterization of synthesized compounds, demonstrating the potential for further applications in synthetic chemistry. [Extracted from the article]

Proximity-dependent biotinylation coupled with mass spectrometry enables the characterization of subcellular proteomes. This technique has significantly advanced neuroscience by revealing sub-synaptic protein networks, such as the synaptic cleft and post-synaptic density. Profiling proteins at this detailed level is essential for understanding the molecular mechanisms of neuronal connectivity and transmission. Despite its recent successful application to various neuronal types, proximity labelling has yet to be employed to study the serotonin system. In this study, we uncovered an unreported inhibitory mechanism of serotonin on horseradish peroxidase (HRP)-based biotinylation. Our result showed that serotonin significantly reduces biotinylation levels across various Biotin-XX-tyramide (BxxP) concentrations in HEK293T cells and primary neurons, whereas dopamine exerts minimal interference, highlighting the specificity of this inhibition. To counteract this inhibition, we demonstrated that Dz-PEG, an aryl diazonium compound that consumes serotonin through an azo-coupling reaction, restores biotinylation efficiency. Label-free quantitative proteomics confirmed that serotonin inhibits biotinylation, and that Dz-PEG effectively reverses this inhibition. These findings highlight the importance of accounting for neurotransmitter interference in proximity-dependent biotinylation studies, especially for cell-type specific profiling in neuroscience. Additionally, we provided a potential strategy to mitigate these challenges, thereby enhancing the accuracy and reliability of such studies. [ABSTRACT FROM AUTHOR]

This report describes a dual catalytic approach for the versatile C−H arylation of arenes under photo‐excitation at room temperature. The cooperative catalysis utilizes iron oxide magnetic nanoparticles (which mostly contain Fe3O4 along with some γ‐Fe2O3) as the potential photocatalyst, which merges with the Pd‐catalyzed C−H activation cycle for the reductive generation of aryl radical from aryl diazonium salt, revealing its photocatalytic activities. The method is applicable to a wide range of aryl coupling partners and different directing groups, demonstrating excellent productivity, nice co‐operativity and recyclability. Adequate control experiments and mechanistic studies assisted in establishing the radical‐based reaction mechanism for the C−H arylation occurring in the heterogeneous phase. [ABSTRACT FROM AUTHOR]

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The reaction of the cyclometalated five‐coordinate 16 electron iridium(III) complex [IrCl(H){P(tBu)2C6H4–κ2P,C}{P(tBu)2Ph}] (1) with the diazonium salt [p‐BrC6H4N2]BF4 in dichloromethane at room temperature was investigated. By spontaneous reductive elimination the iridium(I) complex salt trans‐[IrCl(N2C6H4Br‐p){(P(tBu)2)Ph}2]BF4 (2) was obtained in good yield. Therefore, this observed reaction behavior exhibits the diazonium unit as a strong π‐acceptor group and confirms furthermore the analogy between nitrosyl and aryldiazonium ligands. The new compound 2 has been characterized by standard spectroscopic methods and the molecular structure of 2 was determined by a single‐crystal X‐ray diffraction analysis (monoclinic, space group Cc, Z=4). [ABSTRACT FROM AUTHOR]

The use of diaryl‐substituted vinyl boronates, a class of chemical building blocks with well‐known synthetic utility, is principally limited by the difficulty faced in their preparation. Herein, we present a convenient synthetic strategy based on a gold‐catalyzed Hiyama arylation of (Z)‐β‐(borylvinyl)silanes, which are easily accessible by hydroboration of silylalkynes. By exploiting the highly electronegative nature of the gold(III) intermediate (which is accessed by light‐assisted oxidation using aryl diazonium salts), a selective activation of the silyl group in the presence of the boron moiety is achieved. This opens a route to selectively synthesize diaryl‐substituted vinyl boronates. The reaction shows a broad substrate range, excellent functional group tolerance, and perfect chemoselectivity. Experimental studies and density functional theory (DFT) calculations allowed us to elucidate the mechanism of the reaction. The synthetic potential was demonstrated by downstream transformations providing a facile route to bifunctional phenanthrenes and triaryl‐substituted olefins. [ABSTRACT FROM AUTHOR]

We report a one-pot synthesis of aryl carboxylic acids utilizing HCOOH as a CO surrogate with low Pd-catalyst loading. This operationally simple and scalable method does not require use of a high-pressure reactor, two-chamber reaction vessel, phosphine ligand, or base and proceeds in a relatively short amount of time at ambient temperature. Notably, halides, including iodo and bromo groups, and nitro groups remain intact under these mild reaction conditions. This methodology has been successfully applied to synthesizing 13C-labeled aryl carboxylic acids with satisfactory yields. [ABSTRACT FROM AUTHOR]

The Chemical Communications journal, published by The Royal Society of Chemistry, features a variety of articles on advancements in chemistry. Topics covered include organelle-targeting fluorescent probes, photodynamic therapy, hydrogen production, and battery technologies. The journal aims to connect the global chemistry community and foster scientific progress through original research and discoveries. [Extracted from the article]

Electrochemical grafting of organic molecules to metal surfaces has been well-known as an efficient tool enabling tailored modification of surface at the nanoscale. Among many compounds with the ability to undergo the process of electrografting, iodonium salts belong to less frequently used, especially when compared with the most popular diazonium salts. Meanwhile, due to their increased stability, iodonium salts may be used in situations where the use of diazonium salts is constrained. The aim of this study was to examine the effect of the electrochemical reduction of iodonium salts on the physicochemical properties of Pt electrodes, and the possibility to form pro-adhesive layers facilitating further functionalization purposes. Consequently, we have selected four commercially available iodonium salts (diphenyliodonium chloride, bis(4-tertbutylphenyl)iodonium hexafluorophosphate, (4-nitrophenyl)(2,4,6-trimethylphenyl)iodonium triflate, bis(4-methylphenyl)iodonium hexafluorophosphate), and attached them to the surface of Pt electrodes by means of an electrochemical reduction process. As-formed layers were then extensively characterized in terms of wettability, roughness and charge transfer properties, and used as pro-adhesive coatings prior to the deposition of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate), PEDOT:PSS. Due to the increase in hydrophilicity and roughness, modified electrodes increased the stability of PEDOT:PSS coating while maintaining its high capacitance. IMPACT STATEMENT: Adhesion and charge transfer between PEDOT:PSS and the surface of the electrode are significantly improved by a simple electrode modification strategy using the electrochemical grafting of commercially available iodonium salts. [ABSTRACT FROM AUTHOR]

One of the main modern approaches to the creation of effective drugs is the design of new biologically active substances containing two or more pharmacophore groups in their structure. In recent years, there have been many publications on the synthesis and study of biological activity, including antitumour activity, of new organo-arsenic compounds. It is known that spatially hindered phenols can also have antitumor activity, so the synthesis and study of hybrid compounds based on organo-arsenic compounds and spatially hindered phenols is a relevant area of research. In this work, the modification of 4-aminophenylarsonic acid with 3,5-di-tert-butyl-4-hydroxybenzylacetate was carried out. In contrast to a similar transformation of 2-aminophenylarsonic acid, in this case it was possible to obtain both mono- and di-benzyl derivatives of the acid. Using the Zandmeyer method, the oxime isatin containing an arsonic acid fragment in the fifth position of the heterocycle was synthesised. Azo derivatives containing fragments of para-aminophenylarsonic acid and sterically hindered phenols were obtained. 4-((3,5-Di-tert-butyl-2-hydroxyphenyl)diazenyl)phenylarsonic acid was isolated in pure form. At the same time, it was found that the reaction of the diazonium azo salt of 4-aminophenylarsonic acid with 2-hydroxymethyl-4-tert-butylphenol proceeds in two directions. In addition to the classical diazotisation reaction at the 6-position of 2-hydroxymethyl-4-tert-butylphenol, a diazotisation accompanied by a dehydroxymethylation process occurs. The obtained compounds showed cytotoxic activity against human tumor cell lines M-HeLa (cervical epithelioid carcinoma) and HuTu 80 (duodenal adenocarcinoma cells). The most promising is the sodium salt of 4-((3,5-di-tert-butyl-2-hydroxyphenyl)diazenyl)phenylarsonic acid, which is superior to Tamoxifen and 5-fluorouracil in terms of selectivity index towards M-HeLa and HuTu 80 cells. [ABSTRACT FROM AUTHOR]

Due to the numerous challenges related to selectivity, sensitivity, stability, and operation at standard room temperature, improving the environmental detection of nitrogen oxide presents a considerable defy in the development of novel promising structures in chemical detection. In this study, a new series of p‐type heterojunction nanocomposites based on electrodeposited polypyrrole (PPy) doped with n‐dodecylbenzene sulphonate and either reduced graphene oxide (PPy/RedGO) or reduced graphene oxide functionalized using aryl 4‐carboxybenzene diazonium salt (PPy/RedGO‐arylCOOH) was synthetized using a one‐step chronoamperometric process. The influence of functionalized graphene incorporation on the structural, morphological, and sensory performances of the PPy film was investigated. Its sensitivity and reactivity to NO2 sensing were studied. The structural data confirms that PPy/RedGO‐arylCOOH film is a homogeneous nanocomposite with improved crystalline ordering. It shows optimal NO2 sensing properties compared to the PPy/RedGO composite in terms of sensitivity (0.87 ppm−1), detection limit (2 ppm), response time of 29 s, recovery time of 40 s and reproducibility at room temperature. [ABSTRACT FROM AUTHOR]

Quinones represent a ubiquitous class of natural products, extensively distributed throughout nature. Within these organisms, they fulfil pivotal roles across a spectrum of metabolic processes essential to the organisms. Their privileged core structure is present in a variety of substances explored in medicinal chemistry. Modification of the central core of quinones could give rise to new substances with great potential as drug candidates. In this context, the introduction of an aryl or heteroaryl moiety on the quinone structure can be an important strategy for the development of new potentially bioactive compounds. In the present work, direct arylation methods of quinones reported in the literature are summarized, restricting the text to methods where organometallics are not used as catalysts, nor are organometallic species formed during the catalytic cycle. Radical arylation methods are presented where diazonium salts, hydrazines and arylboronic acids are used as aryl radicals' sources, thermally and photochemically generated. Polar reactions are also presented, that is, through nucleophiles and electrophiles. In most reports, rich aromatics acts as nucleophiles against naphthoquinones, whose electrophilicity is increased by an Brönsted or Lewis acid. Quinones can be the starting materials or generated in situ from phenolic precursors. [ABSTRACT FROM AUTHOR]

A facile synthetic routes to access some new heterocyclic systems containing potent pharmacophoric groups such as pyrazole, pyrazolo[5,1-c]-1,2,4-triazine, 1,2,4-triazino[4,3-a]benzimidazole, and pyridine moieties linked to pyridine-carboxamide moiety are reported. Construction of the target compounds was achieved via reaction of 3-oxo-butanamides 1a,b with hydrazonoyl halides, heterocyclic diazonium salts, and malononitrile derivatives, respectively. The structures of the new products were confirmed by all possible spectral and elemental analyses. The antibacterial assessment showed that one product was moderately active against both K. pneumonia and S. aureus. [ABSTRACT FROM AUTHOR]

Copyright of Baghdad Science Journal is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Direct functionalization of C−H bonds is the most expeditious strategy to build complexity into organic molecules. Unfortunately, most Pd‐catalyzed C−H arylation strategies require high temperatures and/or stoichiometric oxidants. The discovery of metallaphotoredox C−H arylation in 2011 forged a new approach to achieve metal catalyzed C−H arylation at room temperature. Since this discovery, most reports still use explosive diazonium salts as aryl radical precursors. Alternatively, a single report uses bench‐stable diaryliodonium salts, albeit with an Ir‐based photocatalyst. In this study, we develop an organophotoredox manifold that enables Pd‐catalyzed C−H arylation of numerous N‐aryl amide substrates. The results we present are expected to revitalize the use of diaryliodonium salts to achieve room temperature arylations of wide‐ranging classes of C−H bonds. [ABSTRACT FROM AUTHOR]

ABSTRACT Coupling the diazonium salt of sulfadiazine with dibenzoylmethane afforded the 4‐(2‐(1,3‐dioxo‐1,3‐diphenylpropan‐2‐ylidene)hydrazinyl)‐N‐(pyrimidin‐2‐yl)benzene sulfonamide ligand (HL). The ligand (HL) and its Cu(II) complex structure have been investigated via magnetic attraction testing, TGA, FTIR, UV–visible, XRD, and CHN analyses. The spectrum data indicate that the ligand demonstrates monobasic bidentate behavior via deprotonating opposite the oxygen atom of the carbonyl (CO) group and linking using the NH of the hydrazone group (NNH). Copper (II) complex present in octahedral structure. A number of TGA steps (Ea, A, ΔH*, ΔS*, and ΔG*) had their dynamical characteristics computed and described using the Coats–Redfern and Horowitz–Metzger formulas. Molecular studio programmer was utilized to perform density functional theory (DFT) calculations in order to investigate the ideal configuration of HL and its Cu(II) complex. The HL and its copper (II) complex exhibited antitumor effects against MCF‐7 and HepG‐2 cell lines. Furthermore, the width of the inhibition zone was employed to evaluate the in vitro antibacterial effect of HL and a specific complex towards Gram‐negative organisms Escherichia coli (E. coli) and Gram‐positive organisms Staphylococcus aureus. The ligand and its Cu(II) complex were examined using both the viscosity and spectrum of absorption of calf thymus DNA binding experiments. [ABSTRACT FROM AUTHOR]

Recent years have witnessed the emergence of direct intermolecular C(sp3)–H bond functionalization using in situ generated aryl/alkyl radicals as a unique class of hydrogen atom transfer (HAT) agents. A variety of precursors have been exploited to produce these radical HAT agents under photocatalytic, electrochemical or thermal conditions. To date, viable aryl radical precursors have included aryl diazonium salts or aryl azosulfones, diaryliodonium salts, O-benzoyl oximes, aryl sulfonium salts, aryl thioesters, and aryl halides; and applicable alkyl radical sources have included tetrahalogenated methanes (e.g., CCl3Br, CBr4 and CF3I), N-hydroxyphthalimide esters, alkyl bromides, and acetic acid. This review summarizes the current advances in direct intermolecular C(sp3)–H functionalization through key HAT events with in situ generated aryl/alkyl radicals and categorizes the procedures by the specific radical precursors applied. With an emphasis on the reaction conditions, mechanisms and representative substrate scopes of these protocols, this review aims to demonstrate the current trends and future challenges of this emerging field. [ABSTRACT FROM AUTHOR]

Proteomics is a powerful method to comprehensively understand cellular posttranslational modifications (PTMs). Owing to low abundance, tryptic peptides with PTMs are usually enriched for enhanced coverage by liquid chromatography‐mass spectrometry/mass spectrometry (LC–MS/MS). Affinity chromatography for phosphoproteomes by metal‐oxide and pan‐specific antibodies for lysine acetylome allow identification of tens of thousands of modification sites. Lysine methylation is a significant PTM; however, only hundreds of methylation sites were identified by available approaches. Herein we report an aryl diazonium based chemoselective strategy that enables enrichment of monomethyllysine (Kme1) peptides through covalent bonds with extraordinary sensitivity. We identified more than 10000 Kme1 peptides from diverse cell lines and mouse tissues, which implied a wide lysine methylation impact on cellular processes. Furthermore, we found a significant amount of methyl marks that were not S‐adenosyl methionine (SAM)‐dependent by isotope labeling experiments. [ABSTRACT FROM AUTHOR]

New azo Schiff base disperse dyes based on a chromene moiety were synthesized by reacting (2-amino-7-hydroxy-4-(4-methoxyphenyl)-4 H-chromene-3 carbonitrile) and(2-amino-4-(3,4-dimethoxyphenyl)-7-hydroxy-4 H-chromene-3-carbonitrile), with vanillin and ninhydrin, producing new chromene Schiff base derivatives, which in turn were coupled with 2-chloro-4-nitroaniline diazonium salt to give new 4 azo disperse dyes (1–4). The structures of the prepared dyes were confirmed using elemental analysis, 1HNMR spectroscopy, mass spectrometry, and IR. The synthesized dyes were applied to polyester and nylon fabrics using different dyeing techniques: high temperature- high pressure, and ultrasonic dyeing methods. The highest K/S values for all investigated dyes were achieved usinga high temperature-high pressure dyeing technique. Also, the color reflectance of all synthesized dyes with different dyeing shades (1%, 2%, and 3%) was obtained. The fastness properties of the dyed samples using the investigated dyes showed good color fastness toward light, washing, rubbing, and perspiration fastness. The presence of a chromene moiety and Schiff base in the investigated dyes promotes a higher antimicrobial activity on nylon and polyester fabrics against all tested bacteria (E. coli gram-negative and Staphylococcus aureus gram-positive) and two fungi, Aspergillus Niger and Candida albicans. [ABSTRACT FROM AUTHOR]

Azo coupling reactions of (Z)-2-(3,3-dimethyl-3,4-dihydroisoquinolin-1(2H)ylidene)-N-(2,4-xylyl)-acetamide with diazonium salts were used to synthesize 2-(3,3-dimethyl-3,4-dihydroisoquinolin-1-yl)-2-(2-arylhydrazono)-N-(2,4-xylyl)-acetamides. All compounds showed analgesic effects in the hotplate test, exceeding the effect of metamizole sodium. In the case of the most active hydrazone, the defensive reflex time in mice was 27.10 min (compared with 16.60 min for metamizole sodium). [ABSTRACT FROM AUTHOR]

Sulfur‐containing functional groups have garnered considerable attention due to their common occurrence in ligands, pharmaceuticals, and insecticides. Nevertheless, enantioselective synthesis of sulfilimines, particularly diaryl sulfilimines remains a challenging and persistent goal. Herein we report a highly enantio‐ and chemoselective cross–coupling of sulfenamides with aryl diazonium salt to construct diverse S(IV) stereocenters by Pd catalysis. Bisphosphine ligands bearing sulfinamide groups play a crucial role in achieving high reactivity and selectivity. This approach provides a general, modular and divergent framework for quickly synthesizing chiral sulfilimines and sulfoximines that are otherwise challenging to access. In addition, the origins of the high chemoselectivity and enantioselectivity were extensively investigated using density functional theory calculations. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the versatile utility of bio-conjugated peptides and proteins in the fields of agriculture, food, cosmetics and pharmaceutical industry, the design of smart protocols to conjugate and modulate biomolecules becomes highly desirable. During this process, the most important consideration for biochemists is the retention of configurational integrity of the biomolecules. Moreover, this type of bioconjugation of peptide and protein becomes frivolous if the reaction is not performed with precise amino acid residues. Hence, chemo-selective, as well as site-selective reactions, that are biocompatible and possess an appropriate level of reactivity are necessary. Based on click chemistry, there are so many tyrosine (Y) conjugation strategies, such as sulfur-fluoride exchange (SuFEx), sulfur-triazole exchange (SuTEx), coupling with π-allyl palladium complexes, diazonium salts, diazodicarboxyamide-based reagents etc. Among these techniques, diazodicarboxyamide-based Y-conjugation, which is commonly known as the "tyrosine-click (Y-click) reaction", has met the expectations of synthetic and biochemists for the tyrosine-specific functionalization of biomolecules. Over the past one and a half decades, significant progress has been made in the classical organic synthesis approach, as well as its biochemical, photochemical, and electrochemical variants. Despite such progress and increasing importance, the Y-click reaction has not been reviewed to document variations in its methodology, applications, and broad utility. The present article aims to provide a summary of the approaches for the modulation of biomolecules at the hotspot of tyrosine residue by employing the Y-click reaction. The article also highlights its application for the mapping of proteins, imaging of living cells, and in the fields of analytical and medicinal chemistry. [ABSTRACT FROM AUTHOR]

α‐halo alkylboronic esters, acting as ambiphilic synthons, play a pivotal role as versatile intermediates in fields like pharmaceutical science and organic chemistry. The sequential transformation of carbon–boron and carbon–halogen bonds into a broad range of carbon–X bonds allows for programmable bond formation, facilitating the incorporation of multiple substituents at a single position and streamlining the synthesis of complex molecules. Nevertheless, the synthetic potential of these compounds is constrained by limited reaction patterns. Additionally, the conventional methods often necessitate the use of bulk toxic solvents, exhibit sensitivity to air/moisture, rely on expensive metal catalysts, and involve extended reaction times. In this report, a ball milling technique is introduced that overcomes these limitations, enabling the external catalyst‐free multicomponent coupling of aryl diazonium salts, alkenes, and simple metal halides. This approach offers a general and straightforward method for obtaining a diverse array of α‐halo alkylboronic esters, thereby paving the way for the extensive utilization of these synthons in the synthesis of fine chemicals. [ABSTRACT FROM AUTHOR]

New azo pyrimidine and pyrazole derivatives containing a quinazolin-4(3H)-one moiety were synthesized, and their antioxidant and antimicrobial effects were studied. The target compounds were obtained starting from ethyl 2-[2-(4-methoxyphenyl)-4-oxo-3,4-dihydroquinazolin-3-yl]acetate which was reacted with p-phenylenediamine, followed by diazotization, coupling with acetylacetone, and condensation with urea, thiourea, and substituted hydrazines. The synthesized compounds were characterized by melting points, FT-IR and 1H and 13C NMR spectra, and elemental analyses. Some of them showed high antioxidant activity compared to ascorbic acid as standard drug, while the others exhibited moderate to low activity. The title compounds were also evaluated for antimicrobial activity by the well diffusion method and were found to be effective against Gram-positive and Gram-negative bacteria such as Escherichiacoli, Bacilluscereus, and Staphylo-coccus aureus, as well as against the fungi Candida albicans and Rhizopus microsporum, at a concentration of 80 µg/mL. [ABSTRACT FROM AUTHOR]

Measuring pH with an optical sensor requires the immobilization of a chemical recognition phase on a solid surface. Neutral red (NR), an acid base indicator was used to develop two different optical probe configurations. The chemistry of aryl diazonium salts was chosen for the elaboration of this chemical phase, as it enables strong covalent bonds to be established on the surface of metallized glass or metallic surfaces. It also allows the formation of a thick film required to obtain an exploitable spectral response. The surfaces of interest (metallized optical fiber and 316 L stainless-steel mirror) are modelized by flat surfaces (metallized glass plates and 316 L stainless-steel plates). The analytical characterizations carried out (IR, XPS, UV-Visible, and profilometry) show that NR was covalently grafted onto the model surfaces as well as on the surfaces of interest. The supports grafted with NR to develop optical pH probes exhibit spectral changes, particularly the values of pKa, the pH range, and the isosbestic point wavelength. The experimental results show that the optical probe can be used for pH measurements between 4 and 8. [ABSTRACT FROM AUTHOR]

The diverse applications of azo compounds as reagents to bring about chemical synthesis is one of the fastest-growing areas of research. It is well known that the position of the substituents has an important role in the effect of the medicinal, dye industry, thermal, and optical properties of the compounds. In this work, we limit our studies to synthesizing two new diazo dye vanillin derivatives starting from aniline. Nitro aniline compounds 10 and 12 were prepared starting from aniline, and new nitro diazo vanillin derivatives were obtained 4 and 5. Through coupling reactions with vanillin 15 via diazonium salts, 4- hydroxy-3-methoxy-5-((2,4-dinitrophenyl)diazenyl)benzaldehyde 4 was obtained from 2,4-dinitroaniline 10, while 4-hydroxy-3-methoxy-5-((2,4- 6,trinitrophenyl)diazenyl)benzaldehyde 5 resulted from 2,4,6- trinitroaniline 12. The synthesized compounds were characterized by spectroscopic methods; UV-Vis., FTIR, MS, and 1HNMR and melting point determination. The results of the reactions gave good yields of all products. [ABSTRACT FROM AUTHOR]

This review presents the in‐dept analysis of the synthetic approaches towards thiazol‐2(3H)‐imine and embarks at its various biological properties published during 2000 to 2023. The most important method of synthesis involves the reaction of substituted thioureas and α‐halo carbonyl compounds, and condensation and nucleophilic addition of 2‐amino‐1,3‐thiazoline with aldehydes. Additionally, isothiocyanate‐based multicomponent synthesis, and α‐nitroepoxides have been proved as benign precursors for this motif. Several eco‐friendly and solvent‐free synthesis from diazonium salts, acetylenes, tertiary enaminones and thiosemicarbazides have also been reported. This epitome is a unique combination of synthetic methods as well as biological activities like anti‐inflammatory, anti‐bacterial, anti‐cancer, anti‐leishmanial, anti‐microbial, herbicidal, anti‐HIV, and may be a valuable tool for researchers to tailor the synthetic procedures according to specific target structures and applications. Moreover, this review enlightens the applications of thiazol‐2(3H)‐imine as platelet GPIIB/IIIA receptor antagonists, alkaline phosphatase inhibitors, neurodegenerative drug Pifithrin‐α analogues, and skin whitening agents. [ABSTRACT FROM AUTHOR]

Photoredox catalysis provides a green and sustainable alternative for C−H activation of organic molecules that eludes harsh conditions and use of transition metals. The photocatalytic C−N borylation and C−H arylation mostly depend on the ruthenium and iridium complexes or eosin Y and the use of porphyrin catalysts is still in infancy. A series of novel 21‐thiaporphyrins (A2B2 and A3B type) were synthesized having carbazole/phenothiazine moieties at their meso‐positions and screened as catalysts for C−N borylation and C−H arylation. This paper demonstrates the 21‐thiaporphyrin catalyzed C−N borylation and het‐arylation of anilines under visible light. The method utilizes only 0.1 mol % of 21‐thiaporphyrin catalyst under blue light for the direct C−N borylation and het‐arylation reactions. A variety of substituted anilines were used as source for expensive and unstable aryl diazonium salts in the reactions. The heterobiaryls and aryl boronic esters were obtained in decent yields (up to 88 %). Versatility of the 21‐thiaporphyrin catalyst was tested by thiolation and selenylation of anilines under similar conditions. Mechanistic insight was obtained from DFT studies, suggesting that 21‐thiaporphyrin undergo an oxidative quenching pathway. The photoredox process catalyzed by 21‐thiaporphyrins offers a mild, efficient and metal‐free alternative for the formation of C−C, C−S, and C−Se bonds in aryl compounds; it can also be extended to borylation reaction. [ABSTRACT FROM AUTHOR]

A method for the rearrangement of alkyne-tethered cyclohexadienone to furnish meta -enone-substituted anisoles using arene diazonium tetrafluoroborate salts as precatalyst was developed. The reaction proceeds via intramolecular 1,6-enyne cyclization-aromatization and oxetene ring opening. The same protocol was also employed to obtain phthalide-substituted anisoles. The reactions are atom economic, have a broad substrate scope and amenable to gram-scale synthesis. Further synthetic transformations of the products were also performed. [ABSTRACT FROM AUTHOR]

A magnetically isolable iron oxide nanoparticles is introduced as an efficient heterogeneous photocatalyst for non‐directed C−H arylation employing aryl diazonium salts as the aryl precursors. This first‐row transition metal‐based photocatalyst revealed versatile activities and is applicable to a wide range of substrates, demonstrating brilliant efficacy and superior recyclability. Detailed catalytic characterization describes the physical properties and redox behavior of the Fe‐catalyst. Adequate control experiments helped to establish the radical‐based mechanism for the C−H arylation. [ABSTRACT FROM AUTHOR]

The development of an efficient alternative to the widely employed Balz‐Schiemann deaminative fluorination method (i. e. without using aryl diazonium tetrafluoroborate salt) is a challenging task. Herein, we report a convenient one‐pot method for the FeCl3‐nanocellullose mediated mechanochemical synthesis of fluoroarenes through the selective substitution of an aromatic amino group by fluorine group using pyrylium tetrafluoroborate (Pyry‐BF4) and sodium fluoride (NaF) via in situ formation of pyridinium salt intermediate. The scope of the present protocol includes synthesis of thirty‐four organofluorine compounds with excellent yields via a selective substitution (SNAr) of an amino group by fluorine. The presented concise methodology opens a pathway to access new chemical spaces for the late‐stage functionalization in pharmaceutical industries. [ABSTRACT FROM AUTHOR]

The 3-diethylaminophenol (3-DEAP) incorporated anthraquinone mono-azo dye derivative [(E)-1-((4-(diethylamino)-2-hydroxyphenyl)diazenyl)anthracene-9,10-dione] DAAD was synthesized through an electrophilic substitution reaction. The interaction between the -OH functional group and the nitrogen atom of the azo moiety may result in intramolecular proton transfer in the DAAD. DAAD was treated with metal ions such as Co(II), Ni(II), and Cu(II) acetates in a ratio of 2 : 1 revealing an octahedral structure. Many analytical and spectroscopic methods, including UV-vis, FT-IR, (1H and 13C) NMR, HRMS, TGA, VSM, ESR, and powder XRD methods, were used to verify the structural characteristics of the compounds. Additionally, the potency of the in-vitro antioxidant properties of the ligand and its Cu(II), Ni(II), and Co(II) complexes were evaluated; the results revealed that the Co(II) complex showed a maximum percent inhibition of 85 μM against the standard ascorbic acid. [ABSTRACT FROM AUTHOR]

Using a diazonium combination of aniline and 1,3‐diphenylpropane‐1,3‐dione, the Japp‐Klingemann reaction yielded the 1,3‐diphenyl‐2‐(2‐phenylhydrazono)propane‐1,3‐dione ligand (HL). The copper (II) complex has been made using copper (II) acetate salt. The geometry of HL and its Cu (II) chelate were described through CHN analyses, FTIR, UV–Visible, XRD, TGA, and magnetic susceptibility tests. According to the spectral data, the ligand exhibits monobasic bidentate behavior by connecting through the N atom of hydrazone moiety (=N − NH−) by deprotonating beside the oxygen atom of the carbonyl (C=O) group forming octahedral geometry. Density functional theory (DFT) calculations were done by molecular studio software to examine the optimal geometry of HL and its complexity. MCF‐7 and HepG‐2 cell lines demonstrated anticancer action in response to the HL and its copper (II) complex. Additionally, inhibition zone diameter was used to assess the in vitro antibacterial action of HL and particular complex toward Gram +ve bacteria Staphylococcus aureus and Gram‐ve bacteria Escherichia coli (E. coli). Both viscosity and absorption spectra of Calf‐thymus DNA binding experimentations were used to examine the compounds. [ABSTRACT FROM AUTHOR]

The objective of this study is to synthesize novel heterocyclic scaffolds containing a thiophene moiety using easily accessible acetoacetamide as a key synthon. The reaction of acetoacetamide with diazonium salts resulted in the formation of the corresponding thiophene derivatives 4a–c. Additionally, the reaction of acetoacetamide derivative 3 with malononitrile, ethyl cyanoacetate, or 2‐cyanoacetamide, along with elemental sulfur, under refluxing in dioxane containing triethylamine afforded thiophene‐containing derivatives 5a–c. Furthermore, compound 3 reacted with phenyl isothiocyanate in dry dimethylformamide and K2CO3 to yield compound 7. In situ alkylation of the non‐isolable salt 6 was achieved by the addition of methyl iodide, resulting in the formation of methylthio‐thiophene‐2‐carboxamide 8. Compound 7 was employed with numerous alpha‐halogenated reagents in ethanol, affording thiazole derivative 9 and thiophene derivatives 10a and 10b, respectively. Moreover, compound 8 was reacted with hydrazine to produce the 1H‐pyrazole‐4‐carboxamide derivative 11. Additionally, refluxing acetoacetamide derivative 3 with malononitrile and/or ethyl cyanoacetate in dioxane, in the presence of catalytic amount of triethylamine afforded 4‐imino‐3,7‐dimethyl‐4H‐pyrido[1,2‐a]thieno[3,2‐e]pyrimidin‐9(5H)‐one derivatives 12a and 12b. Furthermore, the reactivity of acetoacetamide derivative 3 with 2‐cyanoacetohydrazide was investigated through refluxing the reactants in dioxane, which subsequently yielded the corresponding cyanoacetamide derivative 13. The chemical identity of the newly synthesized compounds was determined by employing infrared spectroscopy (IR), 1H NMR, and 13C NMR techniques. Newly synthesized heterocycles incorporating thiophenes were evaluated for their antioxidant and antimicrobial potentials. Notably, thiophene scaffolds 5a, 10b, 11, and 13 displayed notable antioxidant and antimicrobial activities. [ABSTRACT FROM AUTHOR]

The present work concentrates on synthesizing and adsorption surface investigation of polytetrazole polymer (P-T) created from polyimine (P-S) grafted with sulfadiazine drug. The prepared polymer is synthesized by mechanochemical polycondensation reaction between dialdehyde aromatic compound and diamine aromatic compound by applying appropriate polar solvent and glacial acetic acid at (78 °C) as dependent on the polymerization reaction. The synthetic route to prepare tetrazole polymer (P-T) consists off multi chemical reaction process, firstly the synthesis of polyimine backbone (P-S) (4-(((4'-amino-3,3'-dimethyl-[1,1'-biphenyl]-4- yl)imino)methyl)benzaldehyde) by Schiff base reaction between monomers diamine (o-tolidine) and dialdehyde (terephthalaldehyde). Secondly, is the sulfadiazine azid formation, since the conversion of sulfadiazine drug to sulfadiazine azid (4-azido-N-(pyrimidin-2-yl)benzenesulfonamide) occurred by diazonium salt formation of sulfadiazine at very low temperature (0–5 °C) and then reaction with sodium azide (NaN3) under cool conditions to convert amine group (NH2) to azide group (N3), after that sulfadiazine azide was grafted onto the polyimine backbone (P-S) by cyclization reaction process to form polytetrazole (P-T). All prepared products: sulfadiazine azide, polyimine (P-S) and polytetrazole (P-T) were characterized by FT-IR spectroscopy. Finally, the adsorption surface investigations of the prepared polymers (P-S) and (P-T) were studied for adsorption of Brilliant cresyl blue (BCB) dye. All adsorption results were recorded by using an UV-Vis spectrophotometer. Since the polytetrazole (P-T) gave very good adsorption results when applied to (BCB) dye adsorption, there can be suggestion on the polytertazole polymer applicability in many various environmental and medical applications. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to show the dyeing behaviour of polyester fabrics using four novel heterocyclic disperse dyes. Design/methodology/approach: The four dyes were synthesized based on 5, 5'-(1, 4-phenylene) bis (1, 3, 4-thiadiazol-2-amine) as a diazonium compound. The UV/Vis absorption spectroscopic data of these disperse dyes while dyeing polyester fabrics were investigated. Following this, the dyeing properties of these dyes on polyester fabrics were investigated under acid condition. Findings: The results showed that increasing the dyeing temperature from 80°C to 100°C led to an increase in dye uptake for all dyes, but further increases of the temperature to 130°C led to higher dye uptake for dye 3 as the dye exhaustion increased by about 50% from 55.9% to 91.4%. Originality/value: This study is important as it introduces new dyes for the dyeing of polyethylene terephthalate (PET) fibres with colours that range from yellowish orange to bluish yellow and scarlet red and all with excellent brightness, levelness and depth of shade. [ABSTRACT FROM AUTHOR]

This article discusses the development of a practical method for Fischer indolization, a commonly used synthetic approach in chemistry. The researchers used bench-stable sodium arylhydrazine sulfonates as a substitute for arylhydrazine, which is typically used in Fischer indolization. The sodium arylhydrazine sulfonates were easily obtained from substituted anilines and could be used directly in the reaction without further purification. The method was successful in synthesizing various tetrahydrocarbazoles and tryptamine-based pharmaceutical molecules. The researchers believe that this method has potential applications in the synthesis of indole-based pharmaceutical compounds. [Extracted from the article]

A mini review focused on the chemistry of selenosulfones reported since 2019 is here presented. Initially, methods aimed to the preparation of such moiety are discussed. Successively 1,2‐, 1,3‐, 1,4‐ and 1,7‐addition reactions to C−C single and multiple bonds are illustrated. The forth chapter focuses on electrophilic aromatic substitutions. The fifth chapter deals with C−H functionalizations while the sixth one shows the reactions with aryl diazonium salts or its precursors. The radical coupling with redox active reagents, is the subject of section seventh. Selenosulfones challenged in nucleophilic substitutions and in reactions with phosphorus‐containing compounds are shown in chapter eight and nine followed by the conclusions and perspectives section. [ABSTRACT FROM AUTHOR]

A new series of inorganic–organic hybrid perovskite materials were prepared by microwave-assisted grafting reactions. Simple carboxylic acids, acetic acid, and propionic acid, as well as hydroxyaromatic carboxylic acids, 3,5-dihydroxy benzoic acid (DBA), 5-hydroxyisophthalic acid (HPA), 4-hydroxybenzoic acid (HBA), and 4-hydroxy-4-biphenyl carboxylic acid (HBCA), were reacted with the Dion–Jacobson double-layered perovskite, HLaNb2O7, and its alcoxy derivatives. Grafting was found to not occur with simple carboxylic acids, while those molecules with hydroxyls were all attached to the perovskite interlayers. Reactivity of the hydroxyaromatic carboxylic acids varied with the different layered perovskite hosts where reactions with HLaNb2O7 did not occur, and those with n-propoxy-LaNb2O7 were limited; the greatest extent of reactivity was seen with n-decoxy-LaNb2O7. This is attributed to the larger interlayer spacing available for the insertion of the various hydroxyaromatic carboxylic acid compounds. The loading exhibited by the grafting species was less than that seen with well-known long-chain alkoxy grafting groups. It is expected that the width of the molecules contributes to this where, due to the benzyl groups, the interlayer volume of the grafted moieties occupies a larger horizontal fraction, therefore minimizing the loading to the below half. X-ray powder diffraction and transmission electron microscopy studies found that grafting of the n-decoxy-LaNb2O7 intermediates with the series of hydroxyaromatics resulted in a reduction in crystallinity along with a disruption of the layer structure. Raman data on the series show little variation in local structure except for HBCA, where there appears to be a lengthening of the Nb-O apical linkage and a possible reduction in the distortion of inner-layer NbO6 octahedra. The optical properties of the hydroxyaromatic carboxylic acid grafted perovskites were also investigated using diffuse-reflectance UV-Vis spectroscopy. The band gaps of DBA, HPA, and HBA were found to be similar to the parent (Eg ≈ 3.4 eV), while the HBCA was significantly less by ca. 0.6 eV. This difference is attributed to electron withdrawal from the perovskite block to the HBCA ligand, leading to a lower band gap for the HBCA compound. The methods described herein allow for the formation of a new series of inorganic–organic hybrid materials where the products are of interest as precursors to more complex architectures as well as models for band gap modification of metal oxide photocatalysts. [ABSTRACT FROM AUTHOR]

The interfacial properties between carbon fiber (CF) and thermoplastic resin are relatively weak, which can be problematic for composites in structural applications. Improving the surface roughness of CF is regarded as an effective way to enhance the interface of composites. However, most CF modifying methods are complex and time-consuming, which cannot meet the demand for industrial production. Therefore, it is of great significance to research a fast technique of CF surface modification to strengthen the interface of composites. Herein, a one-pot reaction based on the aryl diazonium salt modification was applied to enhance the interface between CF and poly ether ether ketone (PEEK) resin. Carbon nanotubes (CNTs) were linked to CF by p-phenylenediamine (PPD) via cyclic voltammetry (CV). The surface morphology, chemical characteristics and surface energy of modified CF illustrated the effectiveness of this method, and the interfacial properties of as-prepared modified CF/PEEK demonstrated the increased tendency. All the CF was treated within 5 min and the interfacial shear strength (IFSS) of CF/PEEK was increased to the maximum of 99.62 MPa by aryl diazonium salt modification. This work may shed some light on the industrialized application of CF reinforced high-performance engineering thermoplastic composites. [ABSTRACT FROM AUTHOR]

The reaction of [Ru2(CO)4(µ-H)(µ-PtBu2)(µ-Ph2PCH2PPh2)] (1) with the diazonium salts [PhN2]BF4 and [p-BrC6H4N2]BF4 in dichloromethane at T = 273 K was investigated. The oxidative addition afforded the products [Ru2(CO)4(µ-H)(µ-PtBu2)(µ-Ph2PCH2PPh2)(µ-N2Ph)]BF4 (2a) and [Ru2(CO)4(µ-H)(µ-PtBu2)(µ-Ph2PCH2PPh2)(µ-N2C6H4-p-Br)]BF4 (2b) in good yields. The products have been characterized by NMR and IR spectroscopy and mass spectrometry and the molecular structure of 2a has been determined by a single-crystal X-ray diffraction analysis (monoclinic, space group P21/m, Z = 2). [ABSTRACT FROM AUTHOR]

In this work, by converting 2-(4-aminophenyl) benzimidazole to diazonium salt and coupling it with 8-hydroxyquinoline in an alkaline medium, we were able to synthesize a new ligand, 2-(4 amino phenyl) benzimidazole azo derivative, which was used as the ligand to assess cadmium (II) in aqueous samples. The analysis of cadmium (II) in pure and aqueous components has been established and confirmed using micro-extraction techniques with UV-Vis measurement. In this work, the DLLME method was utilized for the separation, enrichment, and evaluation of cadmium (II) in pure form and aqueous samples by UV-Vis spectroscopy at 414 nm. Several experimental factors were achieved, including the type and volume of dispersive solvent, type and volume of extraction solvents, temperature, and time reaction, and centrifuging time. With a coefficient of determination (R2) of 0.9966 for the spectroscopic technique and 0.9964 for the DLLME method, respectively, the procedures were linear in the range of 1.0 µg/mL-50.0 µg/mL and 1.0 µg/mL-11.0 µg/mL under ideal conditions. The Limit of Detection (LOD) was 0.71 µg/mL and 0.16 µg/mL. The target analyte was recovered from aqueous samples using the spectroscopic approach between 96.6% and 99.6% and the DLLME method between 95.2% and 100.2%, respectively. [ABSTRACT FROM AUTHOR]