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In this research, we first fabricated Fe3O4@Dop-Triazine-CuCl2 nanocatalyst by simple method, then its catalytic activity was investigated in the preparation of various derivatives of aryl-heteroaryl and di-heteroaryl selenides through C–Se coupling reactions of aryl iodides with powder selenium and various derivatives of heterocyclic compounds (with active C–H bonds). The catalyst exhibited spherical morphology with a diameter of approximately 20–30 nm and a magnetic saturation moment of 50.032 emu/g. The hydrocarbon content was measured to be around 12% by weight. In this method, a wide range of aryl-heteroaryl and di-heteroaryl selenides (36 examples) were synthesized with high yields (85–97%) using catalytic amount of the Fe3O4@Dop-Triazine-CuCl2 nanomaterial in the presence of KHCO3 in [BMIM]PF6 as solvent. This method has several remarkable features, which can be mentioned as follows: the synthesis of aryl-heteroaryl and di-heteroaryl selenide derivatives with high yields, performing the reactions in a suitable time (4 h), the applicability of this catalytic system for a wide range of substrates, the use of ionic liquid as solvent, high efficiency of Fe3O4@Dop-Triazine-CuCl2 catalyst, simple separation and high reusability of nanocatalyst. [ABSTRACT FROM AUTHOR]

Developing novel and environmentally friendly green methodologies are critical in synthetic organic chemistry. Here, we investigated the one‐pot, efficient green synthesis of pyrazolo[3,4‐b]pyridine derivatives via a multicomponent approach. The reactions were operated in an aqueous medium by using microwave irradiation and conventional protocols. The green protocol offered high yields of desired product in swift reaction time, and good tolerance under reaction conditions. [ABSTRACT FROM AUTHOR]

Abstract A novel palladium-loaded yolk-shell structured nanomaterial with magnetite core and phenylene-based periodic mesoporous organosilica (PMO) shell (Fe3O4@YS-Ph-PMO/Pd) nanocatalyst was synthesized for the reduction of nitrobenzenes. The Fe3O4@YS-Ph-PMO/Pd was prepared through cetyltrimethylammonium bromide (CTAB) directed condensation of 1,4-bis(triethoxysilyl)benzene (BTEB) around Fe3O4@silica nanoparticles followed by treatment with palladium acetate. This nanocatalyst was characterized by using Fourier transform infrared (FT-IR) spectroscopy, thermal gravimetric analysis (TGA), low-angle and wide-angle powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM) analyses. These analyses showed a magnetic nanomaterial with high chemical and thermal stability for the designed composite. The Fe3O4@YS-Ph-PMO/Pd nanocomposite was employed as a powerful and highly recoverable catalyst in the green reduction of nitroarenes in H2O at room temperature. A variety of nitroarene derivatives were applied as substrate in the presence of 0.9 mol% of Fe3O4@YS-Ph-PMO/Pd catalyst. All nitroarenes were selectively converted to their corresponding amines with high to excellent yields (92–96%) within short reaction times (10–18 min). This catalyst was recovered and reused at least 11 times without significant decrease in efficiency and stability.

A novel palladium-loaded yolk-shell structured nanomaterial with magnetite core and phenylene-based periodic mesoporous organosilica (PMO) shell (Fe3O4@YS-Ph-PMO/Pd) nanocatalyst was synthesized for the reduction of nitrobenzenes. The Fe3O4@YS-Ph-PMO/Pd was prepared through cetyltrimethylammonium bromide (CTAB) directed condensation of 1,4-bis(triethoxysilyl)benzene (BTEB) around Fe3O4@silica nanoparticles followed by treatment with palladium acetate. This nanocatalyst was characterized by using Fourier transform infrared (FT-IR) spectroscopy, thermal gravimetric analysis (TGA), low-angle and wide-angle powder X-ray diffraction (PXRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM) analyses. These analyses showed a magnetic nanomaterial with high chemical and thermal stability for the designed composite. The Fe3O4@YS-Ph-PMO/Pd nanocomposite was employed as a powerful and highly recoverable catalyst in the green reduction of nitroarenes in H2O at room temperature. A variety of nitroarene derivatives were applied as substrate in the presence of 0.9 mol% of Fe3O4@YS-Ph-PMO/Pd catalyst. All nitroarenes were selectively converted to their corresponding amines with high to excellent yields (92–96%) within short reaction times (10–18 min). This catalyst was recovered and reused at least 11 times without significant decrease in efficiency and stability. [ABSTRACT FROM AUTHOR]

An efficient, one-pot quantitative procedure for the preparation of benzo[a]pyrano[2,3-c]phenazine derivatives from four-component condensation reaction of 2-hydroxynaphthalene-1,4-dione, benzene-1,2-diamine, aromatic aldehydes, and malononitrile in the presence of [(EtO)3Si(CH2)3N+H3][CH3COO−] as basic ionic liquid as catalyst in homogenous solution under solvent-free conditions at 90 °C is described. Simple procedure, high yields, short reaction times, and an environmentally benign method are advantages of this protocol. The [(EtO)3Si(CH2)3N+H3][CH3COO−] can be recovered and reused several times without loss of its activity. [ABSTRACT FROM AUTHOR]

–The one-pot three-component combinatorial synthesis of pharmaceutically active 2-amino-7,7-dimethyl-5-oxo-4-(1H-pyrazol-5-yl)-5,6,7,8-tetrahydro-4H-chromene-3-carbonitriles or -carboxylates, which involves a DBU-catalyzed reaction of 1H-pyrazole-5-carbaldehyde, 5,5-dimethylcyclohexane-1,3-dione, and malononitrile or ethyl 2-cyanoacetate at 60–65°C in ethanol for 60–90 min. The procedure offers a few advantages, including versatility, good yields, facility, and environmentally friendly conditions. [ABSTRACT FROM AUTHOR]

MnCoFe2O4@Sucrose-CuS magnetic nanoparticles, containing sucrose as a cheap and available cover group with especial structure, were prepared by a simple and green method. The structure of these nanoparticles was identified by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), thermal gravimetric analysis (TGA), vibrating sample magnetometer (VSM) and Inductively coupled plasma atomic emission spectroscopy (ICP-OES). The obtained results from the FE-SEM images show a spherical structure with an average size of NPs of about 28.47 nm, which is in agreement with the XRD pattern. These novel bio-based magnetic nanoparticles were used as a green and inexpensive nanocatalyst for the synthesis of biscoumarin derivatives via two components reaction 4-hydroxycumarin and aryl aldehydes under reflux conditions and using ethanol as a solvent. The structure of prepared biscoumarin derivatives was identified by FT-IR, 1H- and 13C NMR spectroscopy as well as microanalysis data. The green and accessible synthesis of biscoumarin derivatives, easy workup, short reaction time and high efficiency of the catalyst are some highlights of this clean procedure. The amount of copper on MnCoFe2O4@Scurose-CuS nanoparticles was estimated to be about 2.62 mmol/g by ICP-OES analysis, which shows a slight decrease of about 4.19% after 5 times of use as a catalyst. [ABSTRACT FROM AUTHOR]

The Fe3O4@SiO2@Pr‐N (CH2CH2‐OBuSO3H)3 as magnetic nanocatalyst with Fe3O4 core has been synthesized and used in the synthesis of tetrahydroacenaphtho[1,2‐b]indolones, which was accomplished through the one‐pot four‐component reaction of 5,5‐dimethyl cyclohexane‐1,3‐dione, acenaphthoquinone, arylamines, and active methylenes under solvent‐free conditions at 80°C. Fe3O4@SiO2@Pr‐N (CH2CH2‐OBuSO3H)3 with high magnetical and nontoxic properties has a core‐shell structure. The molecular docking was performed against the cancer target like the crystal structure of the motor protein kinesin spindle protein in complex with adenosine‐5'‐diphosphate and monastrol (pdb: 1Q0B) (2) and crystal structure of Mcl‐1 in complex with compound 7‐(4‐carboxyphenyl)‐3‐[3‐(naphthalen‐1‐yloxy)propyl]pyrazolo[1,5‐a]pyridine‐2‐carboxylic acid (pdb: 3WIX) (3). [ABSTRACT FROM AUTHOR]

Ionic liquids act as green solvents, which can replace the usual traditional solvents which pose both environmental and biological hazard. In the present work 4,4'diamino azobenzene has been condensed with various aliphatic diacids such as succinic acid, glutaric acid, adipic acid, azelaic acid, sebacic acid and Pimelic acid using imidazolium based ionic liquids in the presence of triphenylphosphite(TPP). The resulting azopolyamides have been obtained in high yield with intrinsic viscosity ranging from 0.56 - 0.81 dlg-1. This method is compared with modified Higashi's method. The thermodynamic parameters like ΔG, ΔH and ΔS are calculated by approximate methods such as Freeman & Carroll, Coats & Red fern, Doyle and Murray and White. The resulting polyamides prepared using green condition show increased thermal stability when compared to polyamides prepared by modified Higashi's method. [ABSTRACT FROM AUTHOR]

Quinazolinone synthesis usually requires employing sensitive substrates, hazardous solvents, large excess oxidants, and expensive catalysts. In this study, an efficient and environmentally benign pathway was developed to synthesize 2-phenylquinazolin-4(3H)-one via oxidative coupling between commercially available and stable chemicals, including 2-aminobenzamide and benzyl alcohol without toxic oxidizing agents and transition-metal catalysts. A high yield of the desired product (up to 84%) was obtained at 120°C for 24 h in the presence of oxygen as a green oxidant and t-BuONa as a base. Importantly, the study scope was expanded toward successfully producing various 2-phenylquinazolin-4(3H)-one derivatives in moderate-to-good yields. Furthermore, control experiments proposed that the conversion involved the initial partial oxidation of benzyl alcohol to the benzaldehyde intermediate under basic conditions, followed by the condensation, intramolecular nucleophilic addition, and oxidative dehydrogenation to 2-phenylquinazolin-4(3H)-one.

Novel 2-amino bis(2-phosphonoacetic) acids were prepared by microwave irradiation of a mixture of amine, glyoxylic acid and phosphorous acid. The reaction takes place with various amines including primary and secondary amines and polyamines, but this reaction is more sensitive to steric hindrance of amine than the similar Kabachnik–Fields reaction. Amino acids can be also transformed into the expected bis(2-phosphonoacetic) acids, with the exception of tryptophan, which gives a β-carboline product.

A one-pot multicomponent reaction of a variety of benzaldehydes, dimedone, and 1H-1,2,4-triazol-3-amine for the efficient synthesis of quinazolinone derivatives under green conditions is reported. It was proved that MIL-101(Cr) could carry out successfully this multicomponent strategy to afford target products in high yields. The scope and limitation of this catalytic system concerning the aldehyde substrates were explored. Different aldehydes could be conveniently delivered to quinazolinones at room temperature with short reaction times in an atom-economy way. Notably, MIL-101(Cr) was also characterized by different analytic methods such as FT-IR, SEM, and EDX. The outstanding benefits of this methodology are the availability of substrates, using green conditions, excellent functional group compatibility, and reusability of catalysts, therefore providing easy access to a range of products of interest in organic and medicinal chemistry.

This article describes the use of Pregabalin as a commercially available chiral amino acid in the efficient synthesis of the Passerini‐type condensation products via two‐component condensation of aromatic aldehydes with cyclohexyl isocyanide. All reactions are accompanied with aerobic oxidation of aldehydes in water leading to chiral α‐acyloxycarboxamides with moderate to good enantioselectivities (up to 88 % ee) under green conditions such as nonmetal source. This is the first report of asymmetric synthesis of Passerini products in water. [ABSTRACT FROM AUTHOR]

In the present study, we explored the reactivity of 5‐hydroxymethylfurfural (5‐HMF), a renewable platform chemical, as the aldehyde component in the Groebke‐Blackburn‐Bienaymé (GBB) multicomponent reaction. Given the limited stability of 5‐HMF under conventional conditions used for this reaction, acidic milieu in combination with high temperature or long reaction times, we explored factors which influence the course of the reaction (solvent, catalyst, time, and temperature) within the guidelines of previously reported green reaction conditions. Mild conditions and short reaction times were achieved to obtain good conversion and selectivity values. The reaction scope was exemplified by preparing a small compound library based on the optimized conditions varying the amidine and the isocyanide component. The hydroxymethylfuran moiety present in the GBB products, imidazo[1,2‐a]heterocycles, provides useful functionalization for further transformations, which could expand the diversity of the chemical space. [ABSTRACT FROM AUTHOR]

The reaction of a mixture of cyclohexanone and anthranilic acid in a closed reactor without solvent or even catalyst, under monomode microwave irradiation in controlled conditions, allows the synthesis of tetrahydroacridones. The reaction is possible with several other cyclic ketones. This reaction under monomode microwave irradiation is an example of green synthesis involving the formation of a C-C bond in the absence of catalyst and solvent with the formation of only a benign water molecule. [ABSTRACT FROM AUTHOR]

A novel bifunctional periodic mesoporous organosilica with ionic liquid and phenylene framework supported manganese (BPMO-Ph-IL/Mn) was synthesized, characterized and its catalytic application was investigated. The BPMO-Ph-IL/Mn nanocatalyst was prepared through grafting of ionic liquid on a phenylene based PMO followed by treatment with manganese nitrate. The designed BPMO-Ph-IL/Mn catalyst was characterized using FT-IR, PXRD, TEM, EDX and N2 adsorption–desorption analyses. This was used as an efficient catalyst for selective oxidation of different alcohols. The BPMO-Ph-IL/Mn catalyst was recovered and reused for at least five times without a significant decrease in its efficiency.

• [Triazolamine][Acetate] as a new functionalized stable ionic liquid was prepared. • New (methylsulfonyl)benzo[ h ]chromen-2-amine derivatives were synthesized. • New un-known compounds using a green and novel reusable ionic liquid were prepared. • Basic ionic liquid is stable and reusable in the reaction. • Simple reaction, and easy work-up procedure are advantages of this green protocol. A new functionalized stable ionic liquid as [Triazolamine][Acetate] was prepared for the first times. The novel catalyst was well characterized by various techniques and confirmed molecular structure. The ionic liquid as a novel catalyst was carried out for the green synthesis of new (methylsulfonyl)benzo[ h ]chromen-2-amine derivatives via three components reaction of aldehydes, alpha-naphthol, and (methylsulfonyl)acetonitrile. A simple and an efficient procedure for the synthesis of new un-known compounds using a green and novel reusable ionic liquid as catalyst under thermal conditions in ethanol as solvent was reported. The easy preparation of ionic liquids without any toxic solvent, short reaction times, and simple work-up with excellent yields are advantages of the present research. [Triazolamine][Acetate] as new green catalyst can be reused several times without significant loss of its catalytic activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Fe3O4@SiO2/Schiff base/Pd(II) is reported as a magnetically recoverable heterogeneous catalyst for the chemoselective reduction of aromatic nitro compounds to the corresponding amines through catalytic transfer hydrogenation (CTH). In this regard, a small amount of the nanocatalyst (0.52 mol% Pd) and hydrazine hydrate, showing safe characteristics and perfect ability as the hydrogen donor, were added to the nitro substrates. The experiments described the successful reduction of aromatic nitro compounds with good to excellent yields and short reaction times. The catalyst, due to its magnetic property, could be simply separated from the reaction mixture by a permanent magnet and reused in seven consecutive reactions without considerable loss in its activity. Moreover, the leaching of Pd was only 3.6% after the seventh run. Thus, the most striking feature of this method is to use a small amount of the magnetic nanocatalyst along with a cheap and safe hydrogen source to produce the important amine substances selectively, which makes the method economical, cheap, environmentally friendly, and simple. [ABSTRACT FROM AUTHOR]

A Cu(II)-Schiff base complex supported on functionalized Fe3O4 magnetic nanoparticles (MNPs@Salen-Cu(II)) was obtained as a new heterogeneous nanocatalyst. The nanocomposite materials were characterized by vibrating sample magnetometer (VSM), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA). The catalyst was used in the Henry reaction in order to accomplish one-pot synthesis of nitroaldol derivatives in green conditions. This nanocatalyst can be easily separated from media of reaction using an external magnet and reused several times without loss of its catalytic activity. Furthermore, the non-toxicity of the catalysts and the high yield of the products are other advantages of this method. [ABSTRACT FROM AUTHOR]

A novel magnetic bifunctional ethyl-based periodic mesoporous organosilica supported ionic liquid/manganese complex (Mag-BPMO/Mn) with core–shell structure was synthesized and characterized. The Mag-BPMO/Mn was prepared via grafting of ionic liquid on magnetic Et-based PMO followed by treatment with Mn(NO3)2•4H2O. The physiochemical properties of this nanocatalyst was studied by using Fourier transform infrared (FT-IR) spectroscopy, low angle powder X-ray diffraction (LAPXRD), wide-angle PXRD, energy-dispersive X-ray (EDX) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM) analyses. The Mag-BPMO/Mn was applied as an efficient and reusable heterogeneous nanocatalyst for green synthesis of 4H-pyran derivatives via a one‐pot three‐component reaction. The effect of several parameters such as catalyst loading and solvent were investigated in the catalytic process. The recoverability and reusability of the designed Mag-BPMO/Mn nanocatalyst were also studied under applied conditions.

A facile, efficient, and eco‐friendly strategy to access benzoxazole heterocyclic products has been accomplished through oxidation of catechols followed by condensation/cyclization/aromatization sequences. This process is catalyzed by nanostructured iron(III)‐porphyrin complex to form desired benzoxazole derivatives at room temperature under air condition. The procedure is widely applicable to diverse amines, and can provide the heterocyclic products in a scalable fashion, as well. One of the most significant types of oxidizing agents in nature is the iron‐porphyrin complexes (0.1 mol‐%), existing in the structure of hemoglobin. They have benefits such as low toxicity and high oxidation potential for many substrates. [ABSTRACT FROM AUTHOR]

• Functionalized GO materials remove Cu(II) ions from aqueous solutions. • Functionalized GO-Cu(II) reused material is a catalyst for the coupling of alkynes under green conditions. • Functionalized GO-Cu(II) has been recycled for fifteen times consecutively. This paper deals with the preparation of graphene oxide sheets (GO) modified with magnetite nanoparticles (Fe 3 O 4 NPs) for removing Cu(II) ions from aqueous solutions. Moreover, the recovered Cu(II)-based material was recycled as a catalyst for the homocoupling of a series of alkynes. The adsorption behavior of magnetic GO-based materials towards Cu(II) ions from aqueous solutions was studied as a function of the pH value and the contact time and it was observed that the magnetic GO-based absorbent can be separated quickly from its aqueous solution by using an external magnetic field. Its equilibrium adsorption capacity value for Cu(II) ions was as high as 3.808 ± 0.125 mmol.g−1 under neutral conditions. In addition, the catalytic activity of the resulting [GO-EDA-CAC@Fe 3 O 4 NPs]-BPED-Cu(II) material toward the homocoupling of phenylacetylene into 1,4-diphenylbuta-1,3-diyne was demonstrated with a yield up to 99%. Importantly, the [GO-EDA-CAC@Fe 3 O 4 NPs]-BPED-Cu(II) supported catalyst was consecutively reused for fifteen runs without a significant loss of its activity. [ABSTRACT FROM AUTHOR]

Task specific ionic liquid as a novel and environmental eco-friendly green catalyst has been synthesized and used in the ring opening of epoxides under green conditions. This ionic liquids as solvent, catalyst and reagent afforded the corresponding thiocyanohydrins and azidohydrines with good regioselectivity and very short reaction times. The desired thiocyanohydrins and azidohydrines in 83–93% isolated yields. [ABSTRACT FROM AUTHOR]

Electron-deficient nitrobenzenes were coupled with phenols/alcohols to form diaryl/alkyl aryl ethers by the aid of NiCl2 as the catalyst. The reactions were conducted under ligand- and oxidant-free conditions without the exclusion of air or moisture. The initial studies upon the mechanism of the reaction revealed two solvent-dependent approaches. In molten TBAB, SNAr mechanism seems to be predominated, while, in DMF, the reaction might include the radical species. [ABSTRACT FROM AUTHOR]

In this work, a magnetic hybrid dichromate nanocomposite with triphenylphosphine surface modified superparamagnetic iron oxide nanoparticles (SPIONs) as a recyclable nanocatalyst was designed, prepared and characterized by Fourier transform infrared spectroscopy (FT‐IR) spectra, X‐ray diffraction (XRD) pattern analysis, vibrating sample magnetometer (VSM) curves, X‐ray fluorescence (XRF) analysis, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images and dynamic light scattering (DLS) analysis. Then, it was used in a green and efficient procedure for one‐pot multicomponent synthesis of polyhydroquinoline derivatives by the condensation of aldehydes, dimedone or 1,3‐cyclohexadione, ethyl acetoacetate and ammonium acetate. This protocol includes some new and exceptional advantages such as short reaction times, low catalyst loading, high yields, solvent‐free and room temperature conditions, easy separation and reusability of the catalyst. [ABSTRACT FROM AUTHOR]

A one-pot efficient, practical and eco-friendly synthesis of tocopherol analogues has been developed using water or solvent free conditions via Passerini and Ugi multicomponent reactions. These reactions can be optimized using microwave irradiation or ultrasound as the energy source. Accordingly, a small library of 30 compounds was prepared for biological tests. The evaluation of the antiproliferative activity in the human solid tumor cell lines A549 (lung), HBL-100 (breast), HeLa (cervix), SW1573 (lung), T-47D (breast), and WiDr (colon) provided lead compounds with GI 50 values between 1 and 5 μM. A structure–activity relationship is also discussed. One of the studied compounds comes up as a future candidate for the development of potent tocopherol-mimetic therapeutic agents for cancer. [ABSTRACT FROM AUTHOR]

An efficient and facile one-pot, multi-component reaction for the regio- and diastereoselective synthesis of novel dispirocyclopentanebisoxindoles has been reported by a reaction between phenyl-2-(triphenylphosphoranylidene)ethanone and isatin derivatives. The great advantages of this synthetic protocol are the minimal reaction steps, short reaction time, and operational simplicity. In consequence, a variety of new dispirocyclopentanebisoxindole derivatives with potential medicinal applications were synthesized through one-pot and multi-component reaction in high to excellent yields. [Display omitted] [ABSTRACT FROM AUTHOR]

Supported metallic and bimetallic systems were used for the selective oxidation of but-3-en-1,2-ol (BDO) to hydroxybut-3-en-2-one (HBO), an intermediate in the hydroxymethionine synthesis. All catalysts were active in this reaction. However, bimetallic systems were found more active and selective to HBO in the liquid aqueous phase at 50 °C using molecular O 2 as a benign oxidant. The best performance (87% BDO conversion and 88% HBO selectivity) was observed over a 2%PdPt/TiO 2 catalyst. No metal leaching was observed under the conditions studied. [ABSTRACT FROM AUTHOR]

• Boron nitride nanosheets as efficient support. • Materials with high mechanical and thermal resistance. • Waste-free approach for the synthesis of propargylamines under mild conditions. • Easy recovery and reusability of boron nitride nanosheets supported copper catalyst in A3-couplings. Single or multilayer boron nitride nanoflakes (BNNSs), known as white graphite, due to their have various technological applications unique properties such as mechanical stability, high thermal stability and chemical inertness. In this study, copper (Cu) nanoparticles (NPs) were successfully uniformly attached on BNSS surface by precipitation process. The morphology, composition, and chemical structure of modified BNNS were carefully identified by transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), nitrogen adsorption–desorption, elemental mapping and energy-dispersive X-ray (EDX), UV–vis absorption spectra, and atomic force microscopy (AFM). It was observed that the Cu/BNSs displayed excellent catalytic activity and recyclability for the generation of diverse propargylamines at mild conditions of three component reaction of aldehydes, amines, and alkynes. It also demonstrates that BNNSs act as efficient support to generate heterogeneous catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, the combination of 7,8-dihydroxy-4-methyl coumarin (DHMC) as a novel bidentate O, O-chelating agent and copper(II) acetate monohydrate (2:1 molar ratio) has been found to form an efficient catalytic system. This catalyst provided good to excellent yields in the multi-component click synthesis of 1,4-disubstituted-1,2,3-triazoles by using various structurally diverse organic halides, different non-activated terminal alkynes, and sodium azide. This catalytic system eliminates the need for the isolation of the hazardous azide intermediates which are generated in situ. The reaction is carried out in aqueous phase at room temperature and it can be accelerated by sonication or by increasing the reaction temperature. Moreover, the reaction can be performed in large scale. It is noteworthy that DHMC is commercially available and that it can be easily synthesized with low cost materials. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In the present study, novel optically active poly(amide–imide)/alumina nanocomposites (PAI/Al2O3 NCs) containing different amounts of modified α-Al2O3 nanoparticles (NPs) were synthesized using the ultrasonic-assisted technique. To improve NPs dispersion and increase the possible interaction between NPs and PAI matrix, the surface of α-Al2O3 NP was modified with bioactive diacid coupling agent. The PAI chains were formed from the polycondensation of N-trimellitylimido-l-phenylalanine diacid with 1,5-diamino naphthalene under green conditions. The obtained polymer and inorganic metal oxide NPs were used to prepare chiral PAI/Al2O3 NCs through the ultrasonic irradiation. PAI/Al2O3 NCs were characterized by Fourier transform infrared spectra, x-ray diffraction patterns, field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and ultraviolet–visible (UV-Vis). TGA results confirmed that the heat stability of the prepared NP-reinforced composites was improved compared with the pure polymer. In addition, TEM and FESEM images showed that NPs were dispersed into the polymer matrix at nanoscale. [ABSTRACT FROM AUTHOR]

Stable Pd nanoparticles (Pd NPs) have been uniformly dispersed and immobilized into the metal-organic framework of UiO-66, Pd/UiO-66, by a facile impregnation reduction method. Pd/UiO-66 retains the integrity of the UiO-66 crystal structure and incorporated with ultrasmall Pd NPs(1.70 ± 0.32 nm). Using ammonium formate(AF) as a H-donor and water as solvent under green condition, the optimized 1.16 wt% Pd/UiO-66 catalyst exhibits remarkable activity in the catalytic transfer hydrogenation(CTH) of α-methylstyrene(AMS) into cumin(achieving 99.6% conversion of AMS and almost full selectivity to cumin with an extremely high turnover frequency value 456.7 h−1 at 323.15 K). Pd/UiO-66 also show superior catalytic activity in CTH of unsaturated alkene compounds to saturated compounds with excellent stability and recyclability. Furthermore, the as-formed saturated alkanes can be fast and automatic separated easily from the aqueous catalytic media. This study supplies a general method for immobilizing ultrafine Pd nanoparticles into crystalline MOFs and a "green" path for hydrogenation of unsaturated alkene compounds. [Display omitted] • Stable Pd nanoparticles have been uniformly dispersed and immobilized into UiO-66. • Pd/UiO-66 showed superior activity and stability in the CTH of unsaturated alkene compounds. • As-formed saturated alkanes can be fast and automatic separated easily from the aqueous catalytic media. [ABSTRACT FROM AUTHOR]

Condensation reaction of several ketones with pyrrole in the presence of ferric hydrogen sulfate as a green homogenous acidic catalyst furnished the corresponding pure dipyrromethanes in good yields. Gold nanoparticles were produced through reduction of HAuCl with substituted dipyrromethanes as new reducing agents at room temperature with the exclusion of any capping agent or surfactant. Gold nanoparticles were characterized by transmission electron microscopy, scanning electron microscopy, XRD and UV-visible absorption spectroscopic measurements. It is proposed that in situ formed oxidative products of dipyrromethane, such as polydipyrromethane could serve effectively as a capping agent to preferably adsorb the {111} facets of gold crystals during the reduction process, which leads to the formation of gold nanoparticles. [ABSTRACT FROM AUTHOR]

• A new functionalized ionic liquid as [(EtO) 3 Si(CH 2) 3 NH 3 +][CH 3 COO−] was prepared. • The novel catalyst was carried out for the synthesis of new 2-(phenylsulfonyl)-1 H -benzo[ a ]pyrano[ 2,3-c ]phenazin-3-amine derivatives. • The green ionic liquid was prepared easily. • Simple reaction, and easy work-up procedure are advantages of this green protocols. • Ionic liquid is stable and reusable in the reaction. An efficient, one-pot procedure for the preparation new 2-(phenylsulfonyl)-1 H -benzo[ a ]pyrano[ 2,3-c ]phenazin-3-amine derivatives from four-component condensation reaction of 2-hydroxynaphthalene-1,4‑dione, o -phenylenediamine, aromatic aldehydes, and (phenylsulfonyl)acetonitrile in the presence of [(EtO) 3 Si(CH 2) 3 NH 3 +][CH 3 COO−] as a novel basic ionic liquid as catalyst under solvent-free conditions is described. Simple procedure, high yields, short reaction times and an environmentally benign method are advantages of this protocol. The [(EtO) 3 Si(CH 2) 3 NH 3 +][CH 3 COO−] can be recovered and reused several times without loss of its activity. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A convenient method for the synthesis of hollow mesoporous boron nitride spheres with modified surfaces by CuO (HMBNS/CuO) was reported. • The activity of bifunctional acid-base catalyst was studied for the green synthesis of heterocyclic propellanes in water media at room temperature. • Heterocyclic [3,3,3] propellanes were obtained in good to excellent yields after short reaction times. • Obtained results demonstrated the high efficiency of presented protocol compare with other reported methods. In this study, we try to develop an effective route to the preparation of hollow mesoporous boron nitride spheres (HMBNS) with surface decorated by CuO for the synthesis of some heterocyclic [3,3,3] propellane derivatives under green conditions. Hollow boron nitride spheres were synthesized using the carbon spheres (as a primary template) through the reaction of boric acid and urea follow by surface decoration with CuO. The carbonic template was removed by thermal treatment and hollow boron nitride spheres/CuO (HBNS/CuO) was prepared. In addition to boron and nitrogen which have catalytic role, loading of CuO on the boron nitride shell surfaces, creates a special bifunctional acid-base catalyst to synthesis of heterocyclic [3,3,3] propellane derivatives. The structure of prepared catalyst was characterized by FT-IR, XRD, XPS, BET, FE-SEM, EDX and TEM methods and the influence of the catalyst activity was explored for the synthesis of heterocyclic [3,3,3] propellane derivatives in water media at room temperature. Green conditions, easy recovery of catalyst as well as high to excellent yield of products are some of the merits of presented method. [ABSTRACT FROM AUTHOR]

Front Cover: Synthetic Study of 5-Hydroxymethylfurfural in Groebke-Blackburn-Bienaymé Reaction (Eur. J. Org. Biomass-derived, Green conditions, Groebke-Blackburn-Bienaymé Multicomponent Reaction, 5-Hydroxymethylfurfural, Monowave 50® Keywords: Biomass-derived; Green conditions; Groebke-Blackburn-Bienaymé Multicomponent Reaction; 5-Hydroxymethylfurfural; Monowave 50® EN Biomass-derived Green conditions Groebke-Blackburn-Bienaymé Multicomponent Reaction 5-Hydroxymethylfurfural Monowave 50® 1 1 1 03/28/22 20220315 NES 220315 B The Front Cover b illustrates the use of renewable 5-hydroxymethylfurfural as the aldehyde component in the GBB-3CR multicomponent reaction under environmentally friendly conditions. [Extracted from the article]

[Display omitted] • 3-(Triethoxysilyl)propane-1-aminium formate as a new ionic liquid was prepared. • Novel 2-(phenylsulfonyl)-1 H -benzo[ a ]pyrano[ 2,3-c ]phenazin-3-amines were synthesized. • The green and novel ionic liquid as catalyst was prepared easily. • Simple reaction, and easy work-up procedure are advantages of this green protocols. • Ionic liquid is stable and reusable in the reaction. A new functionalized stable ionic liquid as 3-(triethoxysilyl)propane-1-aminium formate was prepared and characterized. The ionic liquid as a novel catalyst was carried out for the synthesis of new 2-(phenylsulfonyl)-1 H -benzo[ a ]pyrano[ 2,3-c ]phenazin-3-amine derivatives via four-component reaction of 2-hydroxynaphthalene-1,4-dione, o -phenylenediamine, arylaldehydes, and (phenylsulfonyl)acetonitrile. A simple and an efficient procedure for the synthesis of new un-known compounds using a green and novel reusable ionic liquid as catalyst under solvent-free and thermal conditions was reported. The easy preparation of ionic liquids without any toxic solvent, short reaction times, and simple work-up with excellent yields are advantages of the present reaction. [ABSTRACT FROM AUTHOR]

Aim: The reactions were carried out by one pot three-component synthesis, 3- cyanoacetylindole (1) on reaction with aromatic aldehydes (2) and β-naphthol (3) in an aqueous medium in the presence of L-proline as a catalyst under reflux for 30 min, resulting in (3-amino-1- phenyl-1H-benzo[f]chromen-2-yl) (1H-indol-3-yl)methanone (4). The method has many advantages like short reaction times, good yields, and simple workup procedure, besides being green in nature. Pharmacological evaluation of title compounds was done for anti-inflammatory and analgesic activities. Anti-inflammatory activity was carried carrageenan-induced paw edema model in which indomethacin was used as standard and analgesic activity was evaluated by eddy's hot plate method using diclofenac as standard drug., Background: Benzopyrans or chromenes are an important class of heterocyclic compounds due to their broad spectrum of biological activity and a wide range of applications in medicinal chemistry. The chromene moiety is found in various natural products with interesting biological properties. Chromenes constitute the basic backbone of various types of polyphenols and are widely found in alkaloids, tocopherols, flavonoids, and anthocyanins. Indoles are omnipresent in various bioactive compounds like alkaloids, agrochemicals, and pharmaceuticals., Objective: The objective of this study is to synthesize one-pot stepwise Green synthesis, antiinflammatory and analgesic activities of 3-amino-1-phenyl-1H-benzo[f]chromen-2-yl) (1H-indol-3- yl) methanones., Methods: The acute anti-inflammatory effect was evaluated by carrageenan-induced mice paw edema (Ma Rachchh et al., 2011). Edema was induced by injecting carrageenan (1% w/v, 0.1 ml) in the right hind paw of mice. The test compounds 1-12, indomethacin (10 mg/kg), and the vehicle were administered orally one hour before injection of carrageenan. Paw volume was measured with a digital plethysmometer at 0, 30, 60, 90, 120 min after injection. Percentage increase =A-B/ A *100., Results: Carrageenan induced paw edema model was used for anti-inflammatory activity in which animals treated with standard (indomethacin) and test compounds showed a significant decrease in the paw edema. Analgesic activity was estimated using Eddy's hot plate method; animals were treated with standard (diclofenac) and test compounds showed a significant increase in the reaction time., Conclusion: A green, one-pot, step-wise and three-component synthesis of 3-amino-1-phenyl-1Hbenzo[ f]chromen-2-yl) (1H-indol-3-yl) methanone was achieved by using water as a solvent, Lproline as catalyst under reflux conditions. The reactions were carried out in eco-friendly conditions with shorter reaction times, easier workup, and high yields. Anti-inflammatory activity was evaluated by carrageenan-induced paw edema model, where significant anti-inflammatory activity is shown by all the test compounds 4(a-l) compared to standard drug. Analgesic activity was studied by Eddy's Hot plate method and Test compounds 4e, 4f, 4h, 4i, 4j, 4k, 4l showed significant activities compared to the reference drug., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)