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To mitigate global carbon emissions, utilizing bio-based oils instead of petroleum for biodiesel production has emerged as a viable strategy. However, the development of efficient catalysts for the mild conversion of fatty acid esters (the mainly compounds of oils or fats) into diesel-range alkanes remains challenging due to the low reactivity of carbonyl group in esters. Herein, we report an efficient catalyst system for the hydrodeoxygenation of fatty acid esters into diesel-range alkanes under mild conditions over the RemNin@SiO2 catalyst. The catalyst containing a Re/Ni molar ratio of 1.0 showed the best catalytic performance, a 100% conversion and 96.3% selectivity towards n-octadecane/n-heptadecane(C18/C17) were obtained when using the methyl stearate as model compound under mild condition (170 °C and 2.5 MPa H2 pressure), surpassing the catalytic performance of the most catalytic systems reported so far. Characterization results showed that the excellent catalytic performance of the RemNin@SiO2 catalyst was mainly attributed to the formation of ReNi alloy, which enhanced the interaction between the catalyst and the oxygen atom of carbonyl group of esters, thereby activating the carbonyl group and promoting the deoxygenation of fatty acid esters under mild conditions. In addition, the synthesized Re1Ni1@SiO2 bimetallic catalyst has good stability, and after four cycles, the catalyst still exhibits high catalytic performance with above 90% alkane conversion. Re1Ni1@SiO2 catalyzed the hydrodeoxygenation of Methyl Stearate towards alkanes (C18/C17) under mild conditions. [ABSTRACT FROM AUTHOR]

Reducing catalyst costs and reaction energy consumption is a potent way to advance biorefinery energy from fundamental research to industrial implementation. Herein, we developed a series of low‐cost CuCo/Al2O3 catalysts for hydrodeoxygenation of 5‐hydroxymethylfurfural to biofuel 2,5‐dimethylfuran (DMF). Combined characterizations showed CuCo alloy and Co@CuCo core–shell structures were successfully constructed by reducing layered double hydroxides (LDHs) at different temperatures. Detailed catalytic performance studies found that Co@CuCo catalyst achieved a decent DMF yield of 91.7% under 130°C and 1 MPa H2, which is milder than most literatures. While the CuCo alloy catalyst only gave 23.2% yield. H2‐TPD and in situ‐IR indicated the CuCo‐alloy shell can prevent oxidation of Co core, so that maintain its high H2 dissociation capacity. Moreover, the electronic structure changes in the Cu–Co alloy promote the hydrolysis of CO bond. Hence, the local atomic arrangement and corresponding electronic structure in the Co@CuCo structure jointly strengthened the low‐temperature reactivity. [ABSTRACT FROM AUTHOR]

Eucalyptol or 1,8-cineole, a bio-based monoterpene, whose potential has been explored as a viable alternative reaction media for the development of several heterocyclic systems. As an eco-benign solvent eucalyptol has been found to be a promising, bio-competent, green media in our protocols without allowing the involvement of any transition metal catalyst at suitable temperature. In our present work, we carried out the synthesis of 2,3-dihydroquinazolin-4(1H)-one and isoxazolone derivatives from several aldehydes by using this unexplored but effective eco-benign solvent. The use of this recyclable solvent helped us to avoid the use of hazardous, toxic, and harsh reaction conditions toward the synthesis of different desired heterocyclic systems. [ABSTRACT FROM AUTHOR]

In the presence of cesium carbonate, ynones bearing an ortho‐amino group reacted with cyclic β‐ketoesters through conjugated addition/carbon‐carbon σ‐bond cleavage/nucleophilic aromatic substitution tandem reaction to obtain 4‐quinolones fused with medium‐sized rings in good yields. This is the first example of synthesis of 4‐quinolones through base‐promoted insertion reactions of carbon‐carbon triple bonds into carbon‐carbon σ‐bonds. Notable features of this program are mild and transition‐metal‐free reaction conditions. [ABSTRACT FROM AUTHOR]

The electrochemical synthesis of hetero[7]helicenes including pyrrole and furan rings has been established. A single electrochemical operation led to an oxidative heterocoupling and dehydrative cyclization sequence to afford oxaza[7]helicenes in 50–86% yields with 45–77% Faradic efficiencies. Their derivatization and chiroptical properties were also investigated. [ABSTRACT FROM AUTHOR]

In recent decades, direct C–H arylation has become a preferred tool for biaryl coupling over traditional cross-coupling methods owing to its operationally simple protocol, inherent atom and step economy, and reduced metallic waste. Several elegant methods have been developed that offer the facile transformation of usually inert Csp2 –H bonds into Csp2 –Csp2 bonds in a single synthetic operation. Despite many merits, a major drawback to this chemistry comes from the low reactivity of aryl C–H bonds, which often mandate harsh reaction conditions compromising sustainability. Hence, developing reaction protocols that require milder conditions has become an important goal in this area of research. This review article comprehensively highlights the synthesis and mechanistic aspects of direct C–H arylation reactions, which proceed at or below room temperature. 1 Introduction 2 Concepts and Examples 2.1 Transition-Metal-Catalyzed Procedures 2.1.1 Pd Catalysis 2.1.2 Other Metal-Based Procedures 2.1.3 Additive-Free Procedures 2.2 Direct Arylation Polymerization 2.3 Photocatalyzed Procedures 2.3.1 Organometallic C–H-Activation-Based Procedures 2.3.2 Radical-Addition-Based Procedures 2.4 Transition-Metal-Free Procedures 2.4.1 Base-Mediated Procedures 2.4.2 Iodonium- and Diazonium-Salt-Based Procedures 2.5 Electrocatalyzed Procedures 3 Summary and Outlook [ABSTRACT FROM AUTHOR]

1,1'-(2-Hydroxypropane-1,3-diyl) bis(1,4-diazabicyclo[2.2.2]octan-1-ium) tetrachloronickelate (II) ([C3H5OH(DABCO)2]. NiCl4) has been successfully prepared and characterized using energy dispersive X-ray (EDX), thermal gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), inductively coupled plasma atomic emission spectrometer (ICP-AES), field emission scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM) techniques. In continue, the easily preparable nano sized reagent showed efficient catalytic ability in the high yielding synthesis of 1,4-dihydropyridine and pyrano[2,3-d]pyrimidinone derivatives during short reaction times. Ease of preparation of the catalyst, green reaction condition and simple work-up procedure are some of the other important advantages of the reported methods. [ABSTRACT FROM AUTHOR]

Cefonicid is a common second-generation cephalosporin, and the 7-amino-3-[sulphomethyl-1-H-tetrazol-5-yl-thiomethyl]-3-cephem-4-carboxylate monosodium salt is a key synthetic intermediate in its preparation. Despite the considerable international demand for this antibiotic, its preparation is hampered by low synthetic yield, long reaction time, and time-consuming industrial filtration over charcoal after the purification step. In the context of the industrial production of pharmaceutical intermediates, in which the balance between streamlining and enhancing productivity is necessary in order to compete in the global active pharmaceutical ingredients (API) market, we have investigated an efficient and practical procedure for the synthesis of a key cefonicid intermediate that features a telescopic route whose synthetic steps are all performed at room temperature; from the displacement of the acetoxy group with boron trifluoride to crystallization without treatment with charcoal. In other words, a simpler, scalable, cost-effective and energy-saving protocol is herein reported as a means of moving towards commercial manufacturing. The optimization of the process parameters and the industrial-scale impact assessment should pave the way for industrialization.

The development of an efficient, easily prepared, and environmentally friendly catalyst is important for the coupling reaction between CO2 and epoxides. Herein, novel TBAB‐based (tetrabutylammonium bromide, TBAB) deep eutectic solvents (DESs) have been applied in the transformation of CO2 and epoxides into cyclic carbonates with exhibit high activity and selectivity under mild conditions (25 °C, 8 bar CO2), The excellent activity and versatility of the TBAB‐based DESs can be attributed to the hydrogen‐bond interaction between the TBAB and citric acid. Due to hydrogen‐bond interaction between −OH and Br−, the Br− becomes more flexible and facilitates the nucleophilic ring‐opening process. The density functional theory (DFT) method has been used to explore the mechanism governing the CO2 cycloaddition reaction. DFT results imply that intramolecular hydrogen bonding and the flexible nucleophilic Br− anion can significantly accelerate the ring‐opening process. Hence, the ring‐closure reaction may be the rate‐determining step in the CO2 cycloaddition reaction catalyzed by TBAB‐based DESs. Both the experimental and computational results have demonstrated that the synergistic effect between the −OH and Br− in the TBAB‐based DESs play a significant role in the acceleration of the ring‐opening process of the CO2 cycloaddition reaction. [ABSTRACT FROM AUTHOR]

Waste lipids, which are generated in enormous quantities worldwide each year (over 10 million tons), are a type of green and sustainable energy source. The production of renewable fuels from these waste lipids is therefore of great interest due to their contribution to carbon neutrality. The advancement of hydrodeoxygenation (HDO), which enables the production of fossil-like hydrocarbon fuels, offers tantalizing prospects. However, realistically scaling up HDO is still a challenge due to high production costs. Designing a catalyst that enables efficient HDO under mild and solvent-free conditions would significantly contribute to reducing production costs. In this context, the new catalysts, and the corresponding strategies for catalytic HDO processing of waste lipids were reviewed and summarized. First, the HDO reaction pathways, products, and solvation effects were presented. The development of state-of-the-art HDO catalysts with a focus on alleviating the reaction conditions was summarized. Mechanistic insights into HDO conversion based on density functional theory (DFT) calculations were also reviewed. Discussions of other promising deoxygenation strategies such as electro-/photo-catalysis were included. Finally, future developments and directions on the catalytic strategy for mild HDO conversion were suggested. [Display omitted] • Emerging catalysts for solvent-free HDO under mild conditions are reviewed. • Newly developed HDO mechanisms based on DFT calculations are summarized. • Electro-/photo-catalysis conversion shows promise in mild deoxygenation. • Promising strategies and directions for waste lipids upgrading are proposed. [ABSTRACT FROM AUTHOR]

A novel method for the ring‐opening/cyclization of cyclobutanone oxime esters with three different types of alkenes for the synthesis of valuable 2‐pyrrolidones and benzimidazo[2,1‐a]isoquinolin‐6(5H)‐ones is demonstrated for the first time, which uses CuCl as a catalyst and K2S2O8 as an oxidant in a biomass‐derived solvent 2‐methyltetrahydrofuran (2‐MeTHF). This protocol is highly efficient and gives full conversions of the substrates with good functional group compatibility. The use of economic and stable copper catalyst along with inorganic oxidant for the ring‐opening/cyclization in green solvent makes it a benign and sustainable strategy. [ABSTRACT FROM AUTHOR]

[Display omitted] • Under mild reaction conditions, the green technique was employed to carry out a condensation reaction for aromatic aldehyde, 2,4 thiazolidenedione and malononitrile to generate derivatives of pyrano thiazole 6-carbonitrile In comparison to our new complexes, all reaction conditions were optimized for those variable Lewis acid catalysts. • In general tests conducted under high yield, speedy, and environmentally friendly (solvent H 2 O/EtOH) conditions, the FePOph catalyst showed superiority over others. • The heterocatalyst recovery proved successful and could be employed with the same efficiency up to six times before the efficiency started to decrease. In this study, the Fe(III)–porphyrin complex (FePOphy complex) was successfully utilized as an efficient and recyclable catalyst for a one-pot, three-component reaction involving aromatic aldehydes, 2,4-thiazolidenedione, and malononitrile. This reaction led to the synthesis of pyrano thiazole 6-carbonitrile derivatives under environmentally friendly conditions. The structures of the formed compounds were determined through elemental and spectral analyses including infrared (IR, 1H NMR and 13C NMR, CHN and mass spectrometry, confirming the successful synthesis of the desired products. The reactions were conducted in a compassionate environment using a green solvent (H 2 O/EtOH). The outcomes demonstrated the excellent catalytic activity and selectivity of the complexes, which led to good yields of the intended products. As a result, the study offers useful information on the FePOphy complex' synthetic uses, and the creation of effective and environmentally acceptable catalysts, and emphasizes their potential as powerful catalysts for a variety of organic transformations. This strategy's simplicity, safety, commercially accessible catalyst, stability, fast reaction time, and outstanding yields may be used in the industry in the future. [ABSTRACT FROM AUTHOR]

Melamine, as an inexpensive and commercially available reagent, can be efficiently used for the promotion of the synthesis of 3,3′-(4-arylmethylene) bis-(4-hydroxycoumarins), 2,2′-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-ones) and 2-amino-4H-chromene derivatives. In addition to the mild conditions, this method provides other important advantages including simple work-up procedure, environmental friendliness, short reaction times, high yields of the products and use of a cheap, stable and reusable catalyst. [ABSTRACT FROM AUTHOR]

The synthesis of (2‐Phenoxy)benzothiazole and (2‐Phenylthio)benzothiazole has been demonstrated in the presence of iron catalyst under mild reaction conditions. Library of target compounds are prepared under optimized reaction conditions. Both electron donating and electron withdrawing substituent's are readily carried out the reaction to provide their respective target products in moderate to good yield. Mechanistic studies have suggested that the methodology involves intra molecular C‐S cross‐coupling approach. [ABSTRACT FROM AUTHOR]

Furfural has been widely reported as a new‐generation renewable source for the production of chemicals and fuels. In this study, Fe−Pd immobilized Al‐pillared laponite clay material with suitable catalytic properties was explored as an efficient catalyst for the direct conversion of furfural (FAL) into tetrahydrofurfuryl alcohol (THFOL) under the mild reaction conditions (H2 pressure‐ 10 bar, temperature‐ 60 °C and time‐ 4 hrs). The synthesized samples were characterized by several physico–chemical techniques. XRD, FT‐IR, H2‐TPR and ICP‐OES results revealed the successful loading of those bi‐metals into the Al‐pillared laponite structure. Acidity of the sample has been thoroughly investigated by NH3‐TPD and FT‐IR techniques. The catalytic activity of synthesized samples was thoroughly evaluated for the total hydrogenation of FAL for the production of THFOL. It was observed that pure Fe−Pd catalyst showed very low FAL conversion (∼53 %) and THFOL selectivity (∼38 %), whereas the Al‐pillared laponite clay supported Fe−Pd catalyst showed an increase in the FAL conversion and THFOL selectivity up to 95 % and 98 %, respectively. The high performance of Fe−Pd/Al‐pillared laponite catalyst towards the formation of THFOL is not only ascribed to the fine dispersion of Fe and Pd species and their synergistic effect but also due to the high surface area, mesoporosity and suitable acidity of Al‐pillared laponite. The recyclability of the catalyst was also explored thoroughly which confirmed their stability. Sustainability of this process lies in the utilization of low‐value bio‐derived FAL for the production of industrially important THFOL chemical. [ABSTRACT FROM AUTHOR]

Herein, we report a highly efficient Sonogashira‐type cross‐coupling reaction of heteroaryl halides with terminal alkynes under mild transition‐metal‐free conditions using PPh3 and Cs2CO3/NEt3, A wide range of functional groups was tolerated under optimized conditions. Furthermore, the protocol could be extended to the Suzuki‐type cross‐coupling of heteroaryl halides with phenylboronic acid, achieving the corresponding products in good to excellent yields. A test reaction on gram scale delivered the product in reasonably high yield and thus has the potential of promising applications in drug discovery and functional materials. [ABSTRACT FROM AUTHOR]

The cascade synthesis of pyrroles from nitroarenes is an attractive alternative strategy. However, metal catalysts and relatively high temperatures cover the existing reported catalytic systems for this strategy. The development of nonmetallic heterogeneous catalytic systems for the one-pot synthesis of pyrrole from nitroarenes under mild conditions is both worthwhile and challenging. Herein, we describe an exceptionally efficient method for the synthesis of N -substituted pyrroles by the reductive coupling of nitroarenes and diketones over heterogeneous metal-free catalysts under mild conditions. Nonmetallic NC-X catalysts with high activity were prepared from the pyrolysis of well-defined ligands via simple sacrificing hard template methods. Hydrazine hydrate, formic acid, and molecular hydrogen can all be used as reducing agents in the hydrogenation/Paal-Knorr reaction sequence to efficiently synthesize various N -substituted pyrroles, including drugs and bioactive molecules. The catalytic system was featured with good tolerance to sensitive functional groups and no side reactions such as dehalogenation and aromatics hydrogenation. Hammett correlation studies have shown that the electron-donating substituents are beneficial for the one-pot synthesis of N -substituted pyrroles. The results established that the outstanding performance of the catalyst is mainly attributed to the contribution of graphitic N in the catalyst as well as the promotion effect of the mesoporous structure on the reaction.

The reaction of 2‐chloroquinoline‐3‐carbaldehydes with indoline‐2‐thione in ethanol provides a series of novel indolo[3′,2′:5,6]thiopyrano[2,3‐b]quinoline derivatives. The desired products were obtained in short reaction time and high yields (69‐93%) under mild reaction conditions. [ABSTRACT FROM AUTHOR]

The synthesis of 2-(N -aryolamino)benzothiazoles and 2-(N -aryolamino)benzimidazoles has been accomplished in the presence of copper catalyst. These reactions involve C-S and C-N cross-coupling reaction. All electron donating and withdrawing substituent's readily underwent the reaction to give target products in good to excellent yield. In addition, the reaction also gave target product in high yield with bulk scale. Multistep reaction has been developed for the synthesis of substituted 2-(N -Aryolamino)benzothiazoles and 2-(N -Aryolamino)benzimidazoles under moderate reaction conditions. Image 1 • To the best of our knowledge no one has reported for the synthesis of substituted 2-(N -Aryolamino)benzimidazoles in the presence of copper catalyst. • This methodology is general, clean and efficient. • We could find cheap, readily available and air stable copper catalyst for desulphurization. • The reactions are rapid, facile and accomplished at room temperature. • Moreover, all substituents readily underwent the reaction to provide their corresponding target products in good to high yield. [ABSTRACT FROM AUTHOR]

The synthesis of 2‐aminobenzothiazoles has been demonstrated in the presence of transition metal under mild reaction conditions. In this paper, disubstituted thioureas have also been reported from isothiocyanates at room temperature. Subsequently, C−S cross‐coupling reaction was described for the construction of benzothiazoles using cheap, readily available and air stable Iron catalyst. Moreover, no other byproducts could be observed except target products. Furthermore, control experiments were performed for reveal the mechanism. In addition, a broad range of substrate scope has been explored. The synthesis of 2‐aminobenzothiazoles has been demonstrated in the presence of transition metal under mild reaction conditions. In this paper, disubstituted thioureas have also been reported from isothiocyanates at room temperature. Subsequently, C‐S cross‐coupling reaction was described for the construction of benzothiazoles using cheap, readily available and air stable Iron catalyst. Moreover, no other byproducts could be observed except target products. Furthermore, control experiments were performed for reveal the mechanism. In addition, a broad range of substrate scope has been explored. [ABSTRACT FROM AUTHOR]

An efficient and green protocol for highly selective reduction of α,β‐unsaturated aldehydes and ketones at room temperature is described in a range of ionic liquids, in the absence of noble metal catalysts, by using NaBH4 as reducing agent. Most notably, using [P6,6,6,14][N(CN)2] ionic liquid, in absence of organic solvent, within 10 min, 97% conversion of cinnamaldehyde was achieved with 100% selectivity towards cinnamyl alcohol. The ionic liquid was easily recycled without any noticeable decline in activity. The reduction protocol was further extended to a variety of α,β‐unsaturated aldehydes and ketones. A novel protocol for highly selective reduction of a range of α,β‐unsaturated aldehydes and ketones at room‐temperature has been developed. In the absence of organic solvent, using [P6,6,6,14][N(CN)2] ionic liquid, 100% selectivity to cinnamyl alcohol at 97% cinnamaldehyde conversion was achieved within 10 minutes. [ABSTRACT FROM AUTHOR]

Abstract: The generation of reactive singlet oxygen under mild conditions is of current interest in chemistry, biology, and medicine. We were able to release oxygen from dipyridylanthracene endoperoxides (EPOs) by using a simple chemical trigger at low temperature. Protonation and methylation of such EPOs strongly accelerated these reactions. Furthermore, the methyl pyridinium derivatives are water soluble and therefore serve as oxygen carriers in aqueous media. Methylation of the EPO of the ortho isomer affords the parent form directly without increasing the temperature under very mild conditions. This exceptional behavior is ascribed to the close contact between the nitrogen atom and the peroxo group. Singlet oxygen is released upon this reaction, and can be used to oxygenate an acceptor such as tetramethylethylene in the dark with no heating. Thus, a new chemical source of singlet oxygen has been found, which is triggered by a simple stimulus. [ABSTRACT FROM AUTHOR]

Transition-metal-catalyzed C-H functionalization is already a useful tool in organic synthesis, whilst the rapid development of photoredox catalysis provides new pathways for C-H functionalization with high selectivity and efficiency under mild reaction conditions. In this review, recent advances in C-H functionalization through merging transition-metal catalysis with photoredox catalysis are discussed. [ABSTRACT FROM AUTHOR]

We have developed methodology for the synthesis of aryl/alkyl cyanamides from amines in one-pot four steps reaction using cheap, readily available and air stable copper source as catalyst under mild reaction conditions. We have also studied the application of cyanamides. In this connection, we could construct aryl tetrazolamine from cyanamides using click reaction [ABSTRACT FROM AUTHOR]

[Display omitted] Herein, we report a photoredox-catalyzed cross-coupling reaction of N -indolylacetic acids with nitrones to generate indole- N -ethylamines under mild reaction conditions. This reaction has the characteristics of simple operation, mild conditions, easy to obtain biologically relevant indole- N -ethylamines structural motifs not readily accessible by other methods. [ABSTRACT FROM AUTHOR]

A green, simple and eco-friendly three-component condensation for the synthesis of 1-(benzothiazolylamino)methyl-2-naphthols using new magnetic nanoparticles formulated as Fe3O4@SiO2-ZrCl2-MNPs is described. Considering the economic and environmental aspects, the method provides some advantages such as clean procedure, solvent-free conditions, simple operation and work-up, relatively short reaction times and high yields of the products. Moreover the introduced catalyst can be readily recovered up to 4 consecutive runs with consistent activity using an external magnet. [ABSTRACT FROM AUTHOR]

This work describes a mild and efficient approach for the synthesis of aryl amides via catalytic aminocarbonylation of aryl halides with alicyclic amines using a Pd(P tBu3)2/NH4Cl catalyst system. Under mild reaction temperature of 60°C and balloon pressure of CO, 5 mol% Pd(P tBu3)2 with a cheap NH4Cl promoter is sufficient for high yields of aryl amides. The influence of reaction parameters such as reaction temperature, ligand type and promoter on catalytic activity was investigated. This work also discusses the catalytic intermediates in detail, and provides a plausible mechanism based on an acid chloride intermediate. [ABSTRACT FROM AUTHOR]

A catalyst-free, environmentally benign, and simple one-pot multi-component protocol has been developed for the efficient synthesis of novel (benzo[ d ]imidazo[2,1- b ]thiazol-3-yl)-2H-chromen-2-one derivatives in excellent yields using ethanol-PEG-600. This novel and green protocol have the advantages of shorter reaction times, high conversions, and follow the group-assisted-purification (GAP) chemistry process, which can avoid traditional purifications, chromatography and recrystallization. This is the first report for the synthesis of benzo[ d ]imidazo[2,1- b ]thiazol-3-yl)-2H-chromen-2-one. [ABSTRACT FROM AUTHOR]

Electrocatalytic hydrogenation and catalytic thermal hydrogenation of substituted phenols and diaryl ethers were studied on carbon-supported Rh. The rates of electrocatalytic hydrogenation increase with increasingly negative potentials, which have been related with the coverage of adsorbed hydrogen. For electrocatalytic and catalytic thermal hydrogen addition reactions, the dominant reaction pathway is hydrogenation to cyclic alcohols and cycloalkyl ethers. The presence of substituting methyl or methoxy groups led to lower rates compared to unsubstituted phenol or diphenyl ether. Methoxy or benzyloxy groups, however, undergo C–O bond cleavage via hydrogenolysis and hydrolysis (minor pathway). The surface chemical potential of hydrogen can be increased also by generating a H 2 atmosphere above the reaction media, supporting the conclusion that thermal and electrochemical routes share the same reaction pathways. [ABSTRACT FROM AUTHOR]

A domino reaction of palladium(II)-catalyzed dual C-H functionalization with subsequent intramolecular annulation is presented. This method provides a convenient synthesis of a range of symmetrical and unsymmetrical biologically important ( E)-bisindole-2-ones under extremely mild reaction conditions - room temperature, green oxidant and no additive. The reaction mechanism is elucidated in light of the yield values as well as additional control experiment results. [ABSTRACT FROM AUTHOR]

A rapid and efficient ultrasound-promoted protocol for iodination of aromatic and heteroaromatic compounds, using molecular iodine in the presence of aqueous hydrogen peroxide in water without any cosolvent, has produced versatile iodinated organic molecules with potential application in organic synthesis and medicine in short reaction times and good to excellent yields. [ABSTRACT FROM AUTHOR]

Abstract: An efficient copper-catalyzed N-arylation of N-arylsulfonamides with diaryliodonium salts is reported. The reaction employs diaryliodonium salts and N-arylsulfonamides in water at room temperature, giving the products in moderate to excellent yields. [Copyright &y& Elsevier]

Xanthenes and their derivatives as very important classes of organic compounds are key structural elements of many biologically active compounds. These materials are important heterocyclic nucleus of various dyes and drugs. Because of their wide range of pharmacological, industrial and synthetic applications, many methods for the preparation of xanthenes are reported in the literature. In recent years, among the other chemists, introduction of new methods for the preparation of these types of compounds has attracted the attention of Iranian chemists. The result of these efforts is the introduction of appropriate, effective and efficient methods. In this paper, we have a brief review on these methods and their main advantages and important applicabilities. [ABSTRACT FROM AUTHOR]

A mild, efficient, and eco-friendly protocol for the protection of alcohols and phenols as trimethylsilyl ethers has been developed using rice husk ash as a reagent. This reagent is also able to catalyze the acetylation of alcohols, phenols, thiols, and amines with acetic anhydride. All reactions were performed under mild conditions in good to high yields. [Supplementary materials are available for this article. Go to the publisher's online edition ofPhosphorus, Sulfur, and Silicon and the Related Elementsfor the following free supplemental files: Additional text, tables, and figures.] [ABSTRACT FROM AUTHOR]

Abstract: A single step access to fused imidazopyridine involving [bmIm]OH promoted click cyclocondensation of N-methylisatin with 2-aminopyridine has been achieved. The title heterocyclic scaffolds were obtained in excellent yield with high purity. [bmIm]OH was found to be more attractive as it plays the role of solvent, base, and catalyst. [Copyright &y& Elsevier]

Abstract: The reaction between 2,6-dihalophenols and 2-(trimethylsilyl)aryl triflates in the presence of CsF using acetonitrile as solvent at room temperature led to the formation of functionalized diaryl ethers in very good yields. [Copyright &y& Elsevier]

Abstract: An inorganic–organic hybrid complex, {[Cu2(phen)2(OH)2(H2O)]2[α-SiW12O40]}·8H2O 1, (phen=1,10-phenanthroline), has been synthesized under mild reaction conditions and characterized by single-crystal X-ray diffraction, IR spectrum, thermal analyses (TG-DTA) and fluorescent measurement. The crystallographic analysis reveals that in the compound, the Keggin polyanion [α-SiW12O40]4− acts as the inorganic building block, two [Cu2(phen)2(OH)2(H2O)] units covalently bond to it via terminal oxygen atoms of the Keggin anion. An open framework is formed through supramolecular interactions with solvent accessible volume of 18% in the unit-cell. Dehydration and re-adsorption of water in 1 were investigated by X-ray powder diffraction (XRPD).The compound shows thermal stability and photoluminescence property in the solid state. [Copyright &y& Elsevier]

Abstract: A new protocol for the Knoevenagel condensation between β-diketones and aliphatic and aromatic aldehydes promoted by Mg(ClO4)2 under mild conditions is reported. [Copyright &y& Elsevier]

Supercritical water oxidation (SCWO) is a technology that can oxidize various organic (wet) wastes into CO 2. Complete oxidation of specific organics with SCWO goes in tandem with tailored conditions, typically involving elevated operating temperatures, long residence times, high oxidizer-to-waste ratios, or a combination of those, which promote difficulties, e.g., corrosion. These challenges hamper the practical implementation of SCWO, albeit SCWO offers excellent oxidation efficiencies. This work proposes a novel process combining mild supercritical water oxidation (SCWO) with membrane filtration to enhance the oxidation of organics. The modified SCWO works at mild reaction conditions (i.e., 380 °C, 25 MPa and oxidizer equivalence ratios as low as 1.5) to potentially decrease the risks. The membrane filtration discards clean effluent and recycles the retentate (containing incomplete oxidized organics) back to the mild SCWO process for further oxidation, thereafter resulting in near-complete removal of organics. Fresh feed is continuously added, as in the conventional process, along with recycled retentate to guarantee the throughput of the modified SCWO process. A mixture of SCWO-resistant volatile fatty acids (TOC = 4000 mg·L−1) was studied to validate the proposed process. The proposed process in this study enhances the organic decomposition from 43.2% to 100% at mild conditions with only 10% capacity loss. CO 2 was the dominant gas product with traces of CO and H 2. Carbon output in the gas products increased with recirculation and got close to the carbon input of the freshly added feed ultimately. The results indicated that the proposed process maximized the benefits of both technologies, which allows the development of a technological process for supercritical water oxidation, as well as a new stratagem for waste treatment. Unlabelled Image • Effluent recirculation was applied to modify SCWO. • A combination of SCWO and membrane filtration process was proposed. • The membrane retained the majority of incompletely oxidized organics for recycling. • Mild SCWO with recirculation of retentate achieved high oxidation of organics. [ABSTRACT FROM AUTHOR]

The mild and readily available Cu(NO 3) 2 mediated ortho nitration of anilides with broad substrate using K 2 S 2 O 8 as an oxidant in the absence of any other metal catalyst and nitrating agent under mild conditions was reported for the first time. • Regioselective ortho nitration. • Cheap and readily available nitrating source. • Mild reaction conditions. • Broad substrate scope. The mild and readily available Cu(NO 3) 2 mediated ortho nitration of anilides with broad substrate using K 2 S 2 O 8 as an oxidant in the absence of any other metal catalyst and nitrating agent under mild conditions was reported for the first time. [ABSTRACT FROM AUTHOR]

• A mild and efficient strategy for the synthesis of 1,3-thiazolidin-4-ones. • 22 W CFL (compact fluorescence lamp) is used because of nontoxicity and cost effectiveness. • Catalyst and solvent-free reaction conditions. • Operational simplicity and short reaction durability. • Diversified 4-thiazolidinone scaffolds show numerous biological activities. A visible-light-induced, one-pot mild and efficient, multicomponent-tandem synthesis of diversified 1,3-thiazolidin-4-ones under catalyst and solvent-free conditions is reported. Here, visible-light, an ideal source of energy, has been used as photochemical activator to generate C N and C S bonds under radical mechanistic pathway from aromatic amines, aldehydes and thioglycolic acid. The reported methodology can be extensively utilized to explore 1,3-thiazolidin-4-one derivatives with high selectivity, short reaction time, tolerance of functional groups, cost effectiveness and excellent yields. [ABSTRACT FROM AUTHOR]