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In this work, a new ternary-layered double-hydroxide photocatalyst, denoted as Fe3O4/AlZn–Cu, was synthesized using a specific 6.5 : 3 : 7.5 : 1.5 mol mol−1ratio. The rational selection of constituents in this catalyst – Fe3O4for bulk and electron richness effect, AlZn LDH for supporting the photo redox process, and copper as an active site – is thoroughly elucidated. This paper comprehensively investigates the synthesis and characterizes the properties of this magnetic ternary-layered double-hydroxide heterogeneous multifunctional photocatalyst. Several key scientific domains are explored within this study: (i) demonstrating the catalyst's efficacy in synthesizing 1,2,3-triazoles N-acetamide as an active biological candidate; (ii) synthesize a 1,2,3-triazole scaffold in a benign and ambient environment, having biologically active properties (iii) a comprehensive analysis of the catalyst's structural, optical, and electrochemical properties; and (iv) evaluating the potential of newly structured drug candidates, integrating two anti-Alzheimer heterocyclic moieties linked through click chemistry, through in vitroassessment. Employing insights from biorthogonal chemistry, this study establishes a link between two distinct active Alzheimer-targeting biological moieties viaclick chemistry, obviating the need for organic ligands, photosensitizers, and additives. Furthermore, the multifunctional photocatalyst proves to be cost-effective, robust, and recyclable. The stability of the Fe3O4/AlZn–Cu structure allows for efficient recyclability, facilitated by magnetic recovery techniques, demonstrated effectively over five cycles. Extensive analysis of the recycled catalyst is conducted, affirming its potential for sustainable applications.

In the present study, Pd nanoparticles (NPs) supported on α-Fe2O3-decorated melamine-based COFs (Pd/α-Fe2O3@CTF) were employed as photocatalysts for water-mediated photocatalytic one-pot reductive N-formylation of nitroarenes using HCOOH as a sustainable hydrogen and formylation source under visible light irradiation. The desired products were obtained in good to excellent yields at room temperature. The high photocatalytic performance over Pd/α-Fe2O3@CTF was ascribed to redshift absorption in the visible-light region compared to pure CTF, resulting in the enhancement of photocatalytic activity under visible light. By combining CTF with inorganic semiconductor α-Fe2O3, which has significant and widespread visible light absorption, a hybrid heterostructure that increases the photocatalytic activity can be created. Moreover, Pd incorporation can also boost the photogenerated electron–hole separation efficiency. Pd/α-Fe2O3@CTF was found to be photostable and could be reused five times without any loss of its activity.

Graphical abstract:

The phase transition behavior and structure of an ionic liquid crystal (ILC), 1,3 detetradecyl imidazolium bromide [C14H29Im C14H29] Br–, with double alkyl chain lengths and binary mixtures of 4-cyano-4′-pentylbiphenyl (5CB) with [C14Im C14] Br–were studied by wide-angle X-ray scattering, differential scanning calorimetry, and polarizing optical microscopy. These ILCs can form a high-ordered mesophase smectic-A beside the plastic crystalline phases and also the isotropic state because of the formation of a three-dimensional network by noncovalent bonding. The phase behaviors of binary mixtures show a different phase transition compared to each pure compound. Also, the smectic (Sm-A) to I phase transition temperatures in binary mixtures were reduced significantly compared to the pure ones. A metastable phase was found to appear via a supercooled Sm-A phase on the cooling scan rate in a rich ratio of ILCs in binary mixtures. The modified regular solution theory was used to describe the nature of interaction in binary mixtures. The proposed model provided a good description of the asymmetric thermodynamic behavior in the binary system of 5CB and [C14H29Im C14H29] Br–mixtures.

Because of special characteristics of vanadate compound, such as its sustainability, magneticity, high selectivity in reactions and catalytic character, this study aimed to preparation and analyzing novel ceramic iron vanadate (FeVO4) nanofibers. The ceramic nanofibers of iron vanadate were made by the combination of sol-gel and electrospinning methods. First, polyvinyl alcohol (PVA), as a matrix polymer, was mixed separately with ammonium metavanadate (NH4VO3) and iron (III) nitrate (Fe(NO3)3). As a result, the spinnable polymeric gel was obtained from the controlled mixture of these two precursors of ceramic material. Electrospinning of PVA/iron (III) nitrate/ammonium vanadate solution was done using an Electroris setup that enabled preparation of polymeric template nanofiber. Finally, iron vanadate nanofiber was obtained by calcination of polymer nanofiber at controlled temperature. The products were characterized with scanning electron microscope (SEM), energy dispersive X-ray spectroscope (EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometer (VSM) and Brunauer-Emmett-Teller (BET) surface area analysis.

Tungstate ion was heterogenized on the silica-coated magnetite nanoparticles and applied for the selective oxidation of anilines to nitroso arenes—with hydrogen peroxide/urea as oxidant in dimethyl carbonate as solvent—in moderate–good yields (40–96%). The catalyst was characterized using different techniques including Fourier-transform infrared spectroscopy, X-ray powder diffraction, vibrating sample magnetometry, scanning electron microscopy, energy dispersive X-ray and inductively coupled plasma atomic emission spectroscopy (ICP-AES). The catalyst was easily recovered using an external magnet and reused for six times.

Citric acid-coated magnetic nanoparticles (Fe3O4–CA NPs) were successfully prepared and characterized. This magnetic nanocatalyst was employed as an efficient, recyclable, and environmentally benign heterogeneous catalyst for the transamidation of carboxamides, phthalimide, urea and thiourea with amines. Several derivatives of formylated and transamidated products were synthesized in good to excellent yields in the presence of this catalytic system. And, the catalyst could be easily separated from the reaction mixture using an external magnet and can be reused six times without any significant loss in its catalytic activity.

Aqueous formic acid is used for the synthesis of α-aminophosphonates through Kabachnik–Fields reaction applying aromatic amine, phosphite, and carbonyl compounds. Using formic acid as an efficient and low-cost organocatalyst provides environmental friendly, high yields, low reaction time and mild reaction condition. The isolated products were analyzed by IR, NMR, and mass techniques.

We reported here the preparation, characterization, and catalytic ability of a Fe3O4–supported palladium–carbon (Fe3O4–Pd–C) as an efficient catalyst in disproportionation of gum rosin. The magnetic nanocatalyst was prepared by a simple method and was characterized by FTIR, XRD, TEM, N2adsorption–desorption, VSM, and atomic absorption analysis. The prepared catalyst displayed excellent activity in disproportionation of gum rosin. The magnetic Fe3O4–Pd–C catalyst was successfully recycled three times with keeping its catalytic performance. The simplicity of the nanocatalyst production method and simple separation and recyclability, on the other hand, make possible the industrial production and application of the catalyst.

Disproportionate rosin (DPR) is a mixture of rosin acids with dehydro-abietic acid as its major component. Alkaline salts of DPR are used as emulsifier surfactant in emulsion polymerization reactions. In this work, synthesis of DPR by the use of palladium nanoparticles loaded on activated carbon was studied. The nanocatalyst was characterized by TEM, SEM, XRD, N2adsorption–desorption and AAS. The reusability of the prepared nanocatalyst was successfully examined three times with only a very slight loss of catalytic activity.

Magnetically recyclable

Some derivatives of nitroenamines were synthesized in moderate to good yields in the presence of sulfonic acid supported on silica-modified maghemite (γ-Fe2O3@SiO2–OSO3H) as a highly efficient and magnetically separable catalyst. Both up to five times recyclability and the magnetic separation are salient features of this catalytic system.

Herein, we introduce the first magnetic CuO nanoparticles based on carbon nanotubes as a highly intriguing magnetic catalyst in Ullmann-type coupling of aryl halides with phenols. Two facile procedures were used for the preparation of this magnetically separable catalytic system. Having been treated with FeSO4and then H2O2, nanotubes accommodated the resulting iron hydroxides on the walls. The resulting nanocomposite was then exposed to argon atmosphere at 450 °C giving rise to a carbon nanotube-supported α-Fe2O3compound. Ultimately, copper acetate was hydrolysed in the presence of CNT supported α-Fe2O3at 100 °C and our novel catalyst was gained. Some spectroscopic and microscopic techniques such as Infrared spectroscopy (IR), X-ray diffraction spectroscopy (XRD), Vibrational sample magnetometry (VSM), Brunauer–Emmett–Teller (BET), Barrett–Joyner–Halenda (BJH), Inductively coupled plasma (ICP), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) corroborated the structure of the catalyst. The catalyst synthesized showed good activity in C–O cross coupling reactions affording the highest rate of completion. Magnetic feature of the catalyst helped facile separation of it from the reaction medium. The catalyst could also be reused up to six times without any loss of its activity.

Mn3O4 Nanoparticles were synthesized from Mn(OAc)2 by hydrothermal method in water in the presence and absence of ionic liquids (ILs) as template for controlling the size and the shape of nanoparticles. In order to produce nanoparticles which are more similar and uniform in distribution and morphology, ionic liquids have been used. The ionic liquid [BMIm][Cl] caused more uniform nanoparticles as well as small nanoparticles. Structural characterizations revealed that the synthesized nanoparticles were of tetragonal Mn3O4 structure and that they were uniform in the presence of ionic liquid.

A simple and efficient protocol for the chemoselective mono-N-Boc protection of various structurally diverse amines with di-tert-butyl dicarbonate using magnetically recoverable γ-Fe2O3@SiO2 nanoparticles is reported. The catalyst can be easily recovered and recycled without a significant loss in the catalytic activity. No competitive side reactions, such as formation of isocyanate, urea, oxazolidinone, and N,N-di-Boc derivatives were obsereved.

An efficient ZnO nano catalyst, which was readily prepared from Zn(CH3CO2)2, 2H2O and PVP by a chemical solution approach has successfully catalyzed N-tertbutoxy carbonylation of amines. The ZnO nanorods were successful and gave promising results for highly active and chemoselective as well as easily recyclable catalyst for the NBoc protection reaction of a wide variety of amines. The catalyst could be easily recycled for five times without noticeable decrease in catalytic activity. The ZnO nanocatalyst was characterized with XRD and SEM.

Nanohydroxyapatite microsphere (HAp) as an environmentally benign and biocompatible material is found to be efficient catalyst for the synthesis of -hydroxy and -amino phosphonates derived from carbonyl compounds. This heterogeneous catalyst does not require aqueous workup, additionally catalyst can be simply recovered and recycled.

Nanohydroxyapatite microsphere (HAp) as an environmentally benign and biocompatible material is found to be efficient catalyst for the synthesis of α-hydroxy and α-amino phosphonates derived from carbonyl compounds. This heterogeneous catalyst does not require aqueous workup, additionally catalyst can be simply recovered and recycled.

A new mild and chemoselective method for mono-N-protection of amines and amine derivatives as tert-butoxycarbonyl derivatives is reported. The reaction proceeds with lithium perchlorate (20 4;mol %) and pyrocarbonates, and shows general applicability. The catalytic action of LiClO4 is specific for the activation of Boc2O, thus acid-sensitive functionalities of the starting materials remain unchanged in the protection process. This procedure works well for sterically hindered primary amine as well as electron-deficient primary arylamines, primary and secondary amino alcohols, α-amino acid esters, hydroxylamines, hydrazines and sulfonamides.

Summary Following a brief historical account of the initial difficulties of introducing modern sciences, especially the Western art of independent scientific inquiry, into Iran, using data obtained from the ISI (http://access.isiproducts.com/trials) an attempt is made to analyze the apparent present successes of Iranian scientists on the international science market. Using the corresponding ISI data of the publications (1990-2003) of 24 selected young chemistry Ph.D. graduates and present faculty members at various internal academia, a quantitative and qualitative assessment (www.geocities.com/iipopescu) of their achievements has been attempted and the results related to the strengths and weaknesses of the present science policy of the country.

A simple and general one-pot method was developed to give α-amino phosphonates from aldehydes + amines + dimethyl phosphite in LPDE. Optically active α-amino phosphonates were synthesized using ( R)-(+), ( S)-(−) α-methylbenzylamine, ( R)-(−), ( S)-(+) 2-phenylglycinol. ( R)-(+) α-methylbenzylamine affords predominantly ( S)- α-amino phosphonates and ( R)-(−) 2-phenylglycinol leads predominantly to ( R)- α-amino phosphonates.

The sodium tungstate-catalyzed (10 4;mol 4;%) oxidation of primary amines with a urea-hydrogen peroxide complex (UHP) gives the corresponding N-monoalkylhydroxylamines, which are important biologically active compounds, in good to excellent yields. The method is applicable for a wide range of primary amines, including chiral benzylic amines, α-1,2-hydroxylamine and α-amino esters.

A simple and efficent one-pot method was developed to give N-trimethylsilyloxy-α-amino phosphonate derivatives from aldehydes+hydroxylamines+dimethyl(trimethylsilyl)phosphonate in lithium perchlorate/diethyl ether solution (LPDE) in high yields.

The population of Iran has nearly doubled in less than 25 years, while the number of university students has increased more than 10 times and 720 Ph. D. degrees have been awarded in basic science in the past 10 years. Despite the great difficulties that the Iranian scientists have been facing for more than two decades (as a consequence of a social revolution, 8 years of a destructive war imposed by Iraq, excessive brain drain, discriminatory practices by some international journals in publishing the Iranian articles, and unfair sanctions imposed by the industrialized countries) Iran's science is still thriving and the current number of yearly scientific publications exceeds 1500. When normalized with respect to the number of researchers and the research budget, the Iranian scientists seem to outperform most of their counterparts in the advanced industrialized nations. Main reason: total engagement in truncated research activities (basic or applied) leading solely to pure publications; lack of infrastructure for developmental research activities leading to new technologies. The average impact factor of the papers in various fields of basic science seems quite satisfactory considering the difficult conditions the Iranian scientists are working under. Should the research budgets and conditions improve and the unfair sanctions currently imposed by the world politics be eliminated, a far better contribution to the world science can be expected.

Migration of a trimethylsilyl group from oxygen to the a-carbon (retro- [1,3]-Brook rearrangement) in silyl ketene acetals is catalyzed by LPDE/methyl triflate under mild conditions.

a-Hydrazinophosphonates (N-hydroxy-a-aminophosphonates) are generated by lithium perchlorate-catalyzed three-component reaction of aldehydes, N,N-dimethylhydrazine (phenylhydroxylamine) and trimethylphosphite/trimethylsilyl chloride (acetic acid). The method utilizes cheaply available reagents and hence it is a practical and cost effective strategy, compared to other methods available in the literature.

Condensation of N,N-dimethylhydrazine, an aldehyde in lithium perchlorate/diethylether solution (5.0 M) gave N,N-dimethylhydrazone, which were treated with trimethylsilyl-cyanide to afford α-C-cyanohydrazine. These compounds are important precursors of nitrogen-substituted reagents.

The addition of dialkyl acetylenedicarboxylates to isatin, a strong NH acid, in the presence of triphenylphosphine leads to stable crystalline phosphorus ylids in excellent yields and one of the three synthesised compounds (3a)exists as a mixture of two rotational isomers on the basis of variable temperature nmr spectroscopy.

The addition of dialkyl acetylenedicarboxylates to isatin, a strong N–H acid, in the presence of triphenylphosphine leads to stable crystalline phosphorus ylids in excellent yields. Some of these ylid derivatives exist as a mixture of two rotational isomers. Interconversion between these two forms was investigated by variable temperature NMR spectroscopy.

A simple and efficient one-pot method was developed to give α-aminonitriles from aldehydes + amines + TMSCN in LPDE. Optically active α-aminonitriles were snythesized by using ( S)-(−)- or ( R)-(+) α-methylbenzylamine, ( S)-(−) α-methylbenzylamine affords predominantly S-aminonitriles and ( R)-(+) α-methylbenzylamine leads to the R-aminonitriles.

A simple procedure for the reductive amination of aldehydes (including formaldehyde) and ketones using NaBH4is developed.

by reaction of appropriate o‐diamines or amines with orthoesters

Chemoselective monoprotection of primary and secondary amines is achieved in a short reaction time, even in the presence of other functional groups.

Epoxides (I) and (IV) undergo ring‐opening reactions with aliphatic and aromatic amines (II) as nucleophiles under mild conditions to furnish the corresponding β‐amino alcohols in high yields and regioselectivity.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.