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Although covalent organic frameworks (COFs) have earned significant interest in separation applications, the use of COFs in biomolecule separation remains unexplored. We examined the ionic COF Py-BPy2+-COF as an ion exchange material for biomolecule separation. After characterizing the properties of the synthesized COF with a variety of techniques, binding experiments with both large and small biomolecules were performed. High adsorption capacities of amino acids with different hydrophobicity and charge, as well as proteins of different isoelectric points and molecular weights, were determined in batch equilibrium experiments. Desorption experiments with mixtures of model proteins demonstrated an ability to successfully separate one protein from another with the selectivity hypothesized to be a combination of the isoelectric point, hydrophobicity, and ability to penetrate the crystalline material. Overall, the results demonstrated that Py-BPy2+-COF can be exploited as a robust crystalline anion exchange biomolecule separation material.

Hyper-cross-linked microporous organic polymers are a class of porous materials that have captured widespread attention owing to their high surface areas and wide range of monomeric sources. Balancing economy with performance is the initial hurdle when designing effective hyper-cross-linked microporous organic polymers. Herein, we demonstrated an inexpensive sulfurated solvent-knitted hyper-cross-linked microporous polymer scaffold, named sulfur-decorated hyper-cross-linked coal tar (

Carbon dots (CDs), as a new generation of fluorescent nanoparticles, have been greatly considered for different biomedical applications. In the present study, a one-pot hydrothermal method was developed for the synthesis of a series of carbon dots (CDs) for cancer imaging and therapy. Taxane diterpenoids were utilized as the carbon source, different diamines were used as the nitrogen source, and folic acid was used as a targeting agent. High-quality photostable and multicolor (blue and green) carbon nanocrystals with a hexagonal shape, a narrow size distribution of less than 20 nm, and high fluorescence quantum yield of up to 50.4% were obtained from taxanes in combination with

A one-pot process for the efficient synthesis of 3,5-diaryl-1,2,4-selenadiazoles from aryl nitriles has been developed. This tandem transformation was performed in excellent yields (91–98%) via in situ selenoamidation and a subsequent oxidative dimerization reaction. This method features relatively mild reaction conditions, operational simplicity, straightforward separation of the products, and the utilization of inexpensive reagents.

A practical and efficient synthetic procedure to novel chromeno[3,2-d]oxazoles through a one-pot sequential multistep process is presented. This procedure proceeds efficiently in propylene carbonat...

An eco-friendly, straightforward, and three-component condensation/cascade reaction of 4-hydroxycoumarins and (Z)-azlactones to construct diversified dihydro-5′H-spiro[benzo[c]chromene-8,4′-oxazole]-5′,6(7H)-diones as new masked amino acid derivatives has been developed with high to excellent yields and regio- and diastereoselectivity. This metal-free reaction proceeds via a one-pot cascade Michael addition/lactonization/decarboxylation reaction utilizing reusable propylene carbonate as a green solvent. The scale-up examination was also performed, showing high atom economy under the reaction conditions. Moreover, the mechanism of the reaction was further investigated using isotope-labeling, LC-MS monitoring, and TLC-MALDI-MS.

A new covalent organic framework (COF) based on imine bonds was assembled from 2-(4-formylphenyl)-5-formylpyridine and 1,3,6,8-tetrakis(4-aminophenyl)pyrene, which showed an interesting dual-pore structure with high crystallinity. Postmetallation of the COF with Pt occurred selectively at the N donor (imine and pyridyl) in the larger pores. The metallated COF served as an excellent recyclable heterogeneous photocatalyst for decarboxylative difluoroalkylation and oxidative cyclization reactions.

Sulfonic acid-functionalized (SO3H-functionalized) mesoporous MCM-41 catalyst was synthesized by anchoring 3-((3-(trimethoxysilyl)propyl)thio)propane-1-sulfonic acid onto MCM-41-type silica and characterized by FT-IR spectroscopy, elemental analysis and scanning electron microscopy (SEM) techniques. The catalyst was used for the efficient multi-component synthesis of 1H-pyrazolo-[3,4-b]pyridines and spiro-pyrazolo-[3,4-b]pyridines. Notably, the catalyst could be recycled and reused with negligible loss in activity over seven cycles.

1-Azabicyclo[3.3.0]oct-3-en-2-one derivatives were synthesized efficiently through the facile cascade reaction of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or 1,5-diazabicyclo[4.3.0]non-5-ene (DBN) with arylidene azlactones. This research provides a straightforward procedure for the synthesis of a novel class of multicyclic semi-alkaloids which shows good antimicrobial activity. Under catalyst-free, mild, and solventless condition, a wide range of fused tricyclic derivatives was obtained in high yields.

Cancer is one of the main causes of human fatality and finding effective anticancer drugs is a high priority. Modified anticancer medicines have advantages compared to traditional drugs including; better delivery and lower doses. In the present study, the anticancer activity of silver nanoparticles (Ag NPs) synthesized using Taxus baccata extracts was studied on Caov-4 and HeLa cancer cell lines as well as normal human fibroblast cells. Microscopic studies showed significant morphological changes of cancer cells following the exposure to the Ag NPs while MTT assay revealed dose, time and cell line dependent cytotoxicity. The toxic effect of Ag NPs on Caov-4 cells was considerably higher than HeLa cells as > 98% mortality obtained after 72 h incubation of Caov-4 cells with 5 and 20 μg/mL Ag NPs encapsulated by aqueous and ethanolic extract, respectively. Interestingly, aqueous extract encapsulated Ag NPs had no significant toxicity on normal fibroblast cells suggesting potent and selective anticancer activity on cancer cell lines. Flow cytometric analysis revealed a combination of apoptosis and necrosis following the exposure of Ag NPs to cancer cells. Apoptosis was determined as main mechanism of cell death in low concentration of Ag NPs while considerable necrosis (up to 41%) was observed by increasing the Ag NPs dose (up to 10 μg/mL) and incubation time (up to 72 h). The significant DNA damage and change in expression level of caspase 8 , caspase 9 , bcl-2 and c-Abl genes indicated the induction of mitochondrial death pathway following cell exposure to Ag NPs. It can be concluded that the preparation method and stabilizing agents may have major effects on the biological activity of nanoparticles as well as their physicochemical properties.

Several straightforward and practical processes have been established for the construction of 2-aminothiazoles, 1,3-thiazoles and 1,3-selenazoles from aryliodoazides. These strategies successfully proceed with a wide spectrum of substituted thioamides and its derivatives producing the resulting five-membered heterocycles obtained in satisfactory yields. The unique features of these protocols are operational simplicity and highly functional group tolerance, which make them convenient and practical routes for the preparation of various libraries of 2-aminothiazoles, 1,3-thiazoles, and 1,3-selenazoles.

The efficient synthesis of novel fused pyridines via the three component condensation of aldehydes, kojic acid, and 6-amino-1,3-dimethyluracil, catalyzed by the ionic liquid aminopropyl-1,3,5-triazine-2,4-diphosphonium hydrogen sulfate supported on functionalized nano-silica, under solvent-free conditions is reported. Additionally, bis-derivatives of these compounds were smoothly synthesized from dialdehydes. This method has the advantages of mild conditions, high yields, short reaction times, easy work-up, and being environmentally friendly. Moreover, the catalyst can be easily separated from the reaction mixture, recycled, and reused several times without a noticeable decrease in catalytic activity.

A mild and environmentally-benign protocol for the efficient synthesis of polysubstituted pyrroles via a one-pot three-component reaction of amines, α-bromo ketones and dialkyl acetylenedicarboxylate using H 3 PW 12 O 40 as a recyclable heterogeneous catalyst under solvent-free conditions at room temperature is reported. Importantly, the synthesis of symmetrical and unsymmetrical polysubstituted bis-pyrroles has been performed in good yields for the first time, which can be considered as a salient feature of this protocol.

The development of eco-friendly and efficient processes via one-pot multicomponent synthesis is a very attractive topic. In this work, the Erlenmeyer–Plochl azlactone synthesis was carried out through unique, safe, fast and practical conditions without any catalyst, applying a simple microreactor and gave the corresponding products exclusively. A continuous, first microflow synthesis of N-benzoylglycine carbamide derivatives as AT-130 analogues catalyzed by Nafion-H@SPIONs was also established successfully.

We describe herein the first, straightforward, green, and metal-free tandem continuous flow pseudo-four component reaction to form 3-aminohexahydrocoumarins using choline chloride–urea as a natural deep eutectic solvent. This technology exhibited superior yields relative to the batch reactions.

The combination of continuous flow technology with immobilizing of only 0.13 mol% of triflic acid (TfOH) on silica-encapsulated superparamagnetic iron oxide nanoparticles (SPIONs) under solvent-free conditions successfully provided a powerful, efficient, and eco-friendly route for the synthesis of plasticizers. The turnover frequency value in micro-flow conditions varied in the range of 948.7 to 7384.6 h−1 compared to 403.8 to 3099 h−1 for in-flask. This technique works efficiently, encouraging future applications of micro-flow nano-catalysis in green chemistry.

A versatile and straightforward synthetic strategy for the construction of new tetrasubstituted 1,3-diazinones is described. The procedure is based on CsF-catalyzed, microwave-assisted, ring transformation reaction of arylidene azlactones with amidines. Moreover, this technique provides diversified trans- N-(6-oxo-1,4,5,6-tetrahydropyrimidin-5-yl)benzamides with a good antimicrobial activity.

An efficient and facile method for the synthesis of 2-arylindoles, 2-arylimidazo[1,2-a]pyridines and 2-arylquinoxalines by the reaction of various α-bromo ketones with anilines, 2-aminopyridine and 1,2-phenylenediamine, respectively, in the presence of N-methylimidazolium trifluoromethanesulfonate ionic liquid supported on nano-silica ([Hmim]OTf@nano-SiO2) as a reusable catalyst under solvent-free conditions has been developed. The bis-derivatives of these compounds were also prepared efficiently, for the first time, using this catalytic system. All products were obtained in high yields and in short reaction times.

Suzuki reactions catalysed by a palladium(II) complex of a functionalized bis(imidazolium) ligand, PdII(BIM), immobilized on Dowex 50 WX8 and Amberlite IR-120 ion-exchange resins as heterogeneous, recyclable and active catalysts are reported. The catalysts, PdII(BIM)@Amberlite IR-120 and PdII(BIM)@Dowex 50 WX8, were characterized using Fourier transform infrared and diffuse-reflectance UV–visible spectroscopies and scanning electron microscopy. These heterogeneous catalysts are oxygen-insensitive and air- and moisture-stable in CC coupling reactions, and are reusable several times without significant loss of their catalytic activity. Copyright © 2015 John Wiley & Sons, Ltd.

A new supported phosphonium based ionic liquid, propylphosphonium hydrogen carbonate ionic liquid supported on nano-silica (PPHC–nSiO2), was prepared and characterized by FT-IR, TGA, SEM and ICP techniques. The resulting catalyst was used for the efficient synthesis of fully substituted pyridines via a one-pot multicomponent reaction of aldehydes, malononitrile, and thiols under solvent-free conditions. Expedient synthesis of bis-pyridines from dialdehydes and/or dithiols by using this catalytic system can be considered as a noteworthy advantage of this method. Furthermore, there was no obvious loss of catalytic activity even after 5th cycle.

The expansion of practical processes for superferromagnetic nanocatalysts is a very attractive subject. In this work, we successfully developed a new and efficient procedure with combination of continuous flow technology with immobilizing of only 0.35 mol% of Nafion-H on silica-encapsulated supperparamagnetic iron oxide nanoparticles (SPIONs) to maximize catalyst efficiency for the synthesis of β-acetamido ketones. The turnover frequency value varies in the range of 1336 to 1577 h−1 compared to 256–515 h−1 in the conventional stirred reactor. Moreover, the catalyst could be quickly recovered by external magnetic field and could be reused for several reaction cycles without any change in its catalytic activity.

1-Methyl-3-(propyl-3-sulfonic acid)imidazolium triflate supported on magnetic nanoparticles ([HSO3PMIM]OTf–SiO2@MNPs) was prepared by immobilization of [HSO3PMIM]OTf onto the surface of silica-coated Fe3O4 nanoparticles and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), and FT-IR techniques. Efficient synthesis of mono- and bis-isobenzofuran-1(3H)-ones was performed in the presence of this catalyst under thermal conditions and MW irradiation. The catalyst could be easily separated by an external magnet and reused six times under thermal conditions and MW irradiation without significant loss of its activity.

A domino approach to naphtho[2,1-b]furan-2(1H)-one derivatives from (Z)-4-arylidene-2-phenyl-5(4)-oxazolones (azlactones) and 2-naphthols catalyzed by p-TSA with reasonably moderate to high yields, has been developed. This protocol illustrates attractive features including a unique and convenient process.

In the present work, chloromethylated MIL-101(Cr) modified with imidazole, Im-MIL-101, was applied as a support for immobilizing of tetraphenylporphyrinatomangenese(III) chloride. The imidazole-bound MIL-101, Im-MIL-101, not only used as support for immobilization of manganese porphyrin but also applied as a heterogeneous axial base. The Mn(TPP)Cl@Im-MIL-101 catalyst was characterized by UV–vis, FT-IR, X-ray diffraction (XRD), N 2 adsorption, field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX), elemental analysis and inductively coupled plasma (ICP) methods. The catalytic activity of this new catalytic system was investigated in the alkene epoxidation and alkane hydroxylation using NaIO 4 as an oxidant in CH 3 CN/H 2 O at room temperature. This heterogeneous catalyst is highly efficient, stable and reusable in the oxidation of hydrocarbons.

Bi(OTf)3 was found to be an efficient, reusable and high yielding catalyst for the synthesis of dihydropyrano[3,2-b]chromenediones via the three-component reaction of aromatic aldehydes, kojic acid and 1,3-diones. The catalyst could be separated and recovered easily, and was reused for several runs without significant loss of its activity.

Palladium nanoparticles immobilized on nano-silica triazine dendritic polymer (Pdnp-nSTDP) was found to be a highly effective catalyst for the Sonogashira cross-coupling of aryl halides (iodides, bromides, and chlorides) with aromatic and aliphatic terminal alkynes. This reaction was best performed in water as a green solvent in the presence of just 0.01 mol-% of the catalyst at room temperature. Efficient synthesis of V- and star-shaped polyalkynylated molecules with a benzene, pyridine, or pyrimidine central core was also achieved through Sonogashira cross-coupling of dihalo and trihalo aromatics with terminal alkynes in the presence of this catalytic system. The Pdnp-nSTDP catalyst was easily recovered and reused several times without significant loss of reactivity.

Efficient epoxidation of alkenes catalysed by tetraphenylporphyrinatomanganese(III) chloride, [Mn(TPP)Cl], supported on silica coated magnetite nanoparticles, SiO 2 –Fe 3 O 4 , is reported. First, the SiO 2 –Fe 3 O 4 nanoparticles were modified with triethoxysilylpropyl chloride and then with imidazole. In the final step, [Mn(TPP)Cl] was attached to the support via axial ligation. The prepared catalyst was characterized by elemental analysis, FT-IR and diffuses reflectance UV–vis spectroscopic methods, and scanning electron microscopy. This new heterogenized catalyst was used for efficient epoxidation of alkenes with NaIO 4 at room temperature. The catalyst is of high reusability in the epoxidation reactions, in which it was reused several times without significant loss of its catalytic activity.

Palladium nanoparticles (Pd NPs) supported on amino functionalized UiO-66-NH2 (UiO = University of Oslo) metal-organic framework was prepared using a direct anionic exchange method followed by chemical reduction with sodium acetate in methanol. This nano palladium containing catalyst was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), N2 adsorption, inductively coupled plasma atomic emission spectroscopy (ICP-AES), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). The Pd/UiO-66-NH2 catalyst showed excellent activity in Suzuki–Miyaura cross-coupling reaction and reused several times without any appreciable loss of activity even after five consecutive times.

In the present work, tetra(4-pyridyl)porphyrinatomanganese(III) acetate, Mn(TPyP)OAc, was covalently attached to chloromethylated MIL-101, CM-MIL-101, and a new hybrid material was prepared. The Mn(TPyP)OAc/CM-MIL-101 hybrid catalyst was characterized by FT-IR and diffuse reflectance UV–Vis spectroscopic methods, inductively coupled plasma (ICP), X-ray diffraction (XRD), BET and scanning electron microscopy (SEM) methods. This heterogenized catalyst was applied in epoxidation of alkenes and hydroxylation of alkanes with sodium periodate at room temperature. The catalyst reusability was also investigated and no significant metal leaching and decreasing of the catalyst activity were detected.

Di[1,6-bis(3-methylimidazolium-1-yl)hexane] decatangstate ([C6(MIm)2]2W10O32) was found to be a novel, powerful and effective catalyst for the preparation of N-benzoylglycine carbamides as derivatives of AT-130 via one-pot multicomponent reaction performed under microwave irradiations. The products were obtained in high to excellent yields, thus providing a unique strategy to the large-scale synthesis of these compounds.

An efficient, atom-economical, and regioselective synthesis of a wide range of 1,4-disubstituted 1,2,3-triazoles in excellent yields has been achieved via a one-pot three-component reaction of alkynes and sodium azide with organic halides or α-bromo ketones catalyzed by Cu(II)-TD@nSiO2/sodium ascorbate at room temperature. This catalytic system also showed excellent activity in the synthesis of bis- and tris-1,4-substituted 1,2,3-triazoles. Moreover, the catalyst could be recycled and reused for seven cycles without any loss in its catalytic activity.

A wide variety of diaryl sulfides has been synthesized in excellent yields via C–S cross-couplings of aryl/heteroaryl halides with aromatic/heteroaromatic thiols in the presence of palladium nanoparticles immobilized on nanosilica triazine dendritic polymer (Pd np -nSTDP) as a reusable catalyst under thermal conditions and microwave irradiation. Pd np -nSTDP also showed excellent catalytic activity for the preparation of a series of di- and trisulfides with benzene, pyridine, pyrimidine, and/or 1,3,5-triazine as the central cores by one-pot multi C–S cross-coupling reactions.

A novel and one-pot procedure for the synthesis of N-(phenylimino)indazole-1-carbothioamides was reported via three-component condensation of aldehydes, dithizone and dimedone in the presence of [bpy][FeCl4] under solvent-free conditions. This protocol has valuable features of mild and environmentally benign conditions, short reaction times and high yields of desired products.

A highly efficient route for the synthesis of symmetrical and unsymmetrical 1,3-diynes has been developed by Cu(II)-TD@nSiO2/DBU catalyzed homocoupling/heterocoupling of aromatic as well as aliphatic terminal alkynes under aerobic conditions at ambient temperature. The catalyst could be easily recovered and reused several times without significant loss of its activity.

The present study describes the synthesis, characterization, and catalytic activity of Cu(II) containing nanosilica triazine dendrimer (Cu(II)-TD@nSiO2). The prepared catalyst was characterized by FT-IR, TGA, elemental analysis, UV–vis, FE-SEM, TEM, XPS and ICP-OES techniques. The Cu(II)-TD@nSiO2 has been used as an efficient catalyst for the preparation of various benzimidazoles, benzothiazoles, symmetrical bis-benzimidazoles and bis-benzothiazoles under mild conditions. For the first time, we report the synthesis of an unsymmetrical bis-benzimidazole and also a compound containing both benzimidazole and benzothiazole moieties, indicating the efficiency of this catalytic system. The present method offers advantages of excellent yields, short reaction times and simple work-up. Also, the catalyst can be easily recycled and reused several times, which makes this method attractive, economic and environmentally-benign.

This article presents a synthetic method and reaction mechanism of the 1,5-benzothiazepines and 1,5-benzodiazepines derivatives. In this research, 36 thiazepines and diazepines (mostly new) with a new method have been prepared and their structures have been characterized by spectroscopic methods. Crystal structures of a new thiazepine and diazepine (seven-membered rings) have also been determined and compared with thiazine (six-membered ring). In this method, N-methylimidazolium nitrate [Hmim][NO3] has been used as a catalyst that acts as an environmental friendly system.

Efficient alkene epoxidation with sodium periodate catalyzed by manganese(III) salophen supported on nanomagnetic materials is reported. First, the iron nanomagnets were silica coated, functionalized with imidazole and then manganese salophen was successfully bonded to their surface. The catalyst, [MnIII(salophen)Cl]@SiIm-Fe, was characterized by elemental analysis, FT-IR and UV/Vis spectroscopic techniques, SEM and ICP. The [MnIII(salophen)Cl]@SiIm-Fe was used for alkene epoxidation with sodium periodate at room temperature. Different aromatic and aliphatic terminal alkenes were epoxidized efficiently using sodium periodate as an oxidant. The effect of reaction parameters such as solvent and oxidant in the epoxidation of cis-cyclooctene was investigated. This new heterogenized epoxidation catalyst is easily recovered with a magnet and showed no appreciable loss of activity even after four consecutive runs.

The Lewis acidic room-temperature ionic liquid, [bmim][InCl 4 ], was found to be an efficient catalyst for the regio­selective synthesis of fully substituted pyrazoles and pyrazole-fused cyclohexanones through condensation of hydrazones with symmetrical and unsymmetrical 1,3-diketones. This procedure is simple, ­affording the corresponding products in good to high yields.

A new catalyst based on palladium nanoparticles immobilized on nano-silica triazine dendritic polymer (Pdnp-nSTDP) was synthesized and characterized by FT-IR spectroscopy, thermogravimetric analysis, field emission scanning electron microscopy, energy dispersive X-ray, transmission electron microscopy and elemental analysis. The size of the palladium nanoparticles was determined to be 3.1±0.5 nm. This catalytic system showed high activity in the Suzuki–Miyaura cross-coupling of aryl iodides, bromides and chlorides with arylboronic acids and also in the Heck reaction of these aryl halides with styrenes. These reactions were best performed in a dimethylformamide (DMF)/water mixture (1:3) in the presence of only 0.006 mol% and 0.01 mol% of the catalyst, respectively, under conventional conditions and microwave irradiation to afford the desired coupling products in high yields. The Pdnp-nSTDP was also used as an efficient catalyst for the preparation of a series of star- and banana-shaped compounds with a benzene, pyridine, pyrimidine or 1,3,5-triazine unit as the central core. Moreover, the catalyst could be recovered easily and reused several times without any considerable loss of its catalytic activity.

An efficient one-pot synthesis of novel pyrano[3,2-b]pyrazolo[4,3-e]pyridin-8(1H)-ones via three-component condensation of kojic acid, 1-H-pyrazol-5-amines and aldehydes in the presence of a catalytic amount of Zn(OTf)(2) followed by H(2)O(2)-mediated oxidation is reported. Furthermore, the synthesis of 1'H-spiro[indoline-3,4'-pyrano[2,3-b]pyrazolo[3,4-e]pyridine]-2,8'(9'H)-diones were chosen for the library validation.

A rapid and scale up protocol for the synthesis of azlactones by the Erlenmeyer method under solvent-free conditions was developed. Tungstophosphoric acid supported on nano-silica, TPA@nano-SiO2 was used as a heterogeneous catalyst for the synthesis of a wide range of azlactone derivatives. The catalyst was characterized by physicochemical measurements. The procedure was simple and permitted the quantitative isolation of products and catalyst under thermal conditions. The recycled catalyst was reused more than 5-times without loss of catalytic activity.

An efficient protocol for the excellent diastereoselective synthesis of pyrazolines via a three-component reaction of aldehydes, hydrazines and dimethyl acetylenedicarboxylate (DMAD) in the presence of a bifunctional Bronsted acidic ionic liquid as a reusable catalyst under solvent-free conditions is reported. Easy work-up, short reaction times, high yields of the products and an environmentally benign procedure avoiding toxic organic solvents are other significant features of this method.

The epoxidation of alkenes with hydrogen peroxide catalyzed by [PZnMo 2 W 9 O 39 ] 5- , ZnPOM, supported on ionic liquid-modified silica, Im-SiO 2 , is reported. The immobilized catalyst, [ZnPOM@Im-SiO 2 ] was characterized by elemental analysis, X-ray diffraction (XRD), scanning electron microscopy (SEM), FT-IR and UV–Vis spectroscopic methods. This new synthesized hybrid catalyst was applied for efficient epoxidation of various olefins with aqueous H 2 O 2 in acetonitrile under reflux conditions. This solid catalyst can be easily recovered by simple filtration and reused several times without significant loss of its catalytic activity.

Efficient epoxidation of olefins catalyzed by MoO2(acac)2 supported on amines functionalized MWCNTs is reported. The MWCNTs bearing carboxylic acid groups were modified with 2-aminophenol and 2-aminothiophenol. These amine–MWCNTs act as bidentate ligand for attachment of Mo catalyst. These catalysts were characterized by elemental analysis, scanning electron microscopy, FT-IR and diffuse reflectance UV–Vis spectroscopic methods. The prepared catalysts were used for efficient epoxidation of different alkenes such as cyclic and linear ones with tert-butyl hydroperoxide in refluxing 1,2-dichloroethane. These heterogeneous catalysts can be reused several times without significant loss of their catalytic activity.

The efficient synthesis of novel fused pyridines via the three component condensation of aldehydes, kojic acid, and 6-amino-1,3-dimethyluracil, catalyzed by the ionic liquid aminopropyl-1,3,5-triazine-2,4-diphosphonium hydrogen sulfate supported on functionalized nano-silica, under solvent-free conditions is reported. Additionally, bis-derivatives of these compounds were smoothly synthesized from dialdehydes. This method has the advantages of mild conditions, high yields, short reaction times, easy work-up, and being environmentally friendly. Moreover, the catalyst can be easily separated from the reaction mixture, recycled, and reused several times without a noticeable decrease in catalytic activity.

An expeditious, straightforward and efficient synthesis of diversely naphtho[1,2-e][1,3]oxazines via one-pot condensation reaction of β- naphthol, 3-amino-5-methylisoxazole and arylaldehydes catalyzed by bismuth(III) trifluoromethanesulfonate is described. The reaction preferentially afforded 1,3-trans oxazines.

A novel, diastereoselective, one-pot synthesis of new bis-Betti bases via condensation of dihydroxynaphthalene, two equivalents of aryl aldehydes, and two equivalents of 3-amino-5-methylisoxazole is reported. Conversion into the adducts was almost quantitative without the use of solvent or catalyst. The reaction conditions are very simple and enable easy isolation of the product.

Nano-silica sulfuric acid as a heterogeneous, eco-friendly and reusable catalyst was used in the synthesis of 1,3,5-triarylbenzenes via triple-self condensation of acetophenones. All reactions were performed under solvent-free conditions and microwave irradiation. Short reaction times, high yields, easy isolation and purification of products and good reusability of this catalyst are the mainspring to choose for the preparation of 1,3,5-triarylbenzenes.