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In this study, a simple, cost-efficient and green protocol has been described for the synthesis of biscoumarin and bisdimedone derivatives via one-pot Knoevenagel–Michael reaction of aromatic aldehydes with 4-hydroxycoumarin and dimedone, respectively. This approach has defined a new way of synthesizing products (4a-i and 5a-i) in high yields using carbon sulfonic acid as a heterogeneous solid acid catalyst. All the reactions have been executed in a greener medium in short reaction times with high-to-excellent yields. This organic synthesis adheres to the principles of green chemistry as the catalyst is cheap, gentle toward environment, easy to handle and reusable up to six cycles, easily separable through filtration, green reaction media and high yield of derivatives in short reaction time. The structure of the synthesized compounds was established by spectral analysis.

New three-component reaction was developed via one-pot strategy for the synthesis of functionalized 3,3′-disubstituted oxindoles and spirooxindole through the reaction among isatin, malononitrile, and acetone/indole/nitromethane/acetylacetone/dimedone in ethanol as solvent without base. It was observed that all the mixed ligand transition metal complexes with triphenylphosphine worked as the efficient catalysts. The present methodology agreements several advantages, including simplicity of the preparation and handling of the catalyst, simple and easy work-up, short reaction times, high yields of the products.

Green solventless preparation of dihydropyrano[3,2-b]chromenediones was developed by a three-component reaction (3-CR) of dimedone, different aldehydes, and kojic acid that catalyzed with nano-silica-MCM‐41‐kojic acid‐Ni as a reusable, efficient, and high yielding nanocatalyst. The reactions were completed at 100 °C in 20 min using 5 mg of nanocatalyst under neat conditions to synthesize 1 mmol of the product in high yield. Nano-silica-MCM‐41‐KA‐Ni was prepared by the post-grafting method and characterized using XRD, ICP, EDX, TGA, DTA, SEM, and TEM analyses. The used nanocatalyst was easily recovered using centrifugation and effectively reutilized 5-recycle without considerable changes in its silicate structure mesoporosity and an important decrease in its catalytic activity.

In this paper, a convenient, one-pot, for the straightforward synthesis of pyrano[2,3-b]quinoline and benzo[h]pyrano[2,3-b]quinoline derivatives is presented, which includes a three-component reaction of (2-chloroquinoline-3-carbaldehyde, 2-chlorobenzo[h]quinoline-3-carbaldehyde), and 1-phenyl-2-(1,1,1-triphenyl-λ5- phosphanylidene)ethan-1-one (Wittig reagent) with the active methylene compounds such as (benzoylacetonitrile, dimedone, 1,3-dimethylbarbituric acid, 4-hydroxycoumarin and 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one), during the two processes of C–C bond formation (Michael addition) and intramolecular cyclization (by the attack of the oxygen atom of active methylene compounds). Advantages of this protocol include easily accessible starting materials, excellent yields (65–98%), absence of a metal catalyst and simple workup procedure (the pure products were obtained simply by washing the products with EtOH). A series of pyrano[2,3-b]quinoline and benzo[h]pyrano[2,3-b]quinoline derivatives have been synthesized in excellent yields (65–98%) via a one-pot three-component reaction of (2-chloroquinoline-3-carbaldehyde, 2-chlorobenzo[h]quinoline-3-carbaldehyde) and 1-phenyl-2-(1,1,1-triphenyl-λ5-phosphanylidene)ethan-1-one (Wittig reagent) with the active methylene compounds such as (benzoylacetonitrile, dimedone, 1,3-dimethylbarbituric acid, 4-hydroxycoumarin and 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one), during the two processes of C–C bond formation (Michael addition) and intramolecular cyclization (by the attack of the oxygen atom of active methylene compounds). Advantages of this protocol include easily accessible starting materials, excellent yields (65–98%), absence of a metal catalyst and simple workup procedure (the pure products were obtained simply by washing the products with EtOH).

An effective and environmentally friendly Fe3O4-PVP nanocomposite functionalized with sulfonic group, Fe3O4-PVP-SO3H, was synthesized and characterized as the heterogeneous nanocatalyst for one-pot synthesis of xanthene derivatives via condensation reaction of various aldehydes and dimedone in ethanol media. The catalyst was efficient, and can be separated easily from the reaction mixture and recovered rapidly by an external magnetic field. It can be used five times without significant loss of its activity. Physicochemical properties were characterized using different techniques including FT-IR, XRD, FE-SEM, EDS, TGA, and VSM to illustrate the structure of the catalyst. The presence of sulfonic group on the surface of the catalyst was confirmed by these analyses. Large number of the acidic groups on the surface of the PVP layer led to the more activity of the catalyst and consequently, the yield of xanthene increases. The products were obtained in high yields with short reaction times.

A novel series of bis(sulfanediyl)bis(tetrahydropyrimido[4,5-b]quinoline-4,6-diones) which are linked to benzene, pyridine, or thieno[4,5-d]thiophene cores were prepared to via multicomponent reaction of bis(sulfanediyl))bis(6-aminopyrimidin-4(1H)-ones) with two equivalents of both dimedone and the appropriate aromatic aldehyde. The target molecules were alternatively prepared via the bis-alkylation reactions of the appropriate 5-aryl-2-thioxohexahydropyrimido[4,5-b]quinoline-4,6-dione with the corresponding dibromo compounds.

The current study deals with the synthesis of some novel pyrimidine derivatives by the reaction of aromatic aldehydes, 2-aminobenzothiazole, and dimedone in the presence of thiamine hydrochloride (VB1) as an organocatalyst. The use of VB1 as a catalyst has eradicated the peril of metal contamination in the products that is viable for eco-friendly pathways and proven to be a better catalyst under sustainable conditions. The mechanism of the reaction involved Knoevenagel condensation followed by Michael addition. The designed protocol has many fascinating features, viz. high product yields, eco-friendly, milder reaction conditions, avoiding the use of hazardous solvent, and easily recoverable and reusable catalyst. The good functional group tolerance with a series of derivatives has been demonstrated. Molecular docking studies were performed on the synthesized compounds using Staphylococcus aureus dihydropteroate synthase (saDHPS) (6CLV) and DNA gyrase (1KZN) proteins. Furthermore, the binding mode of the ligands with the protein study was quite promising. Among the synthesized compounds, compound 5e was found to be the most potent and showed good binding interactions and the highest docking score against both proteins, 1KZN and 6CLV.

A trinuclear cobalt cluster complex was prepared into the nanocages of dealuminated Y zeolite ([Co3(O)(CH3COO)6(py)3]-DAZY) and characterized by XRD, FT-IR, EDS, FE-SEM, AAS and BET-BJH analyses. The elemental content of Cobalt in [Co3(O)(CH3COO)6(py)3]-DAZY was estimated to be about 5.5 mg/g support on the basis of atomic absorption spectroscopy. The catalytic activity of [Co3(O)(CH3COO)6(py)3]-DAZY was evaluated in the synthesis of tri series of spiro indoline derivatives in a library synthesis via the condensation of isatins, malononitrile or ethylcyano acetate, and active methylene compounds (4-hydroxycoumarine, dimedone and pyrazoline-5-one). Corresponding products were obtained in good to excellent yields. Short reaction time, high yield of product, structural diversity of products, absence of organic solvents and the use of water as a green solvent, non-toxicity, stability and reusability of the catalyst are noteworthy advantages of the current work.

In this study, the Zr-based metal–organic framework, UiO-66-NH2, was modified with ionic liquid (dibutylimidazolium bromide) to generate a platform for supporting an organocatalyst of guanidine. After an anion exchange, the prepared hybrid system was denoted as UiO-66-NH2-ILPF6–-guanidine. The catalyst was characterized by different techniques such as PXRD, FTIR, TEM, SEM–EDS, TGA, and BET. The basic heterogeneous catalyst was then utilized for the synthesis of xanthene derivatives via a reaction of aldehydes with dimedone. Various types of aromatic aldehydes were employed for the synthesis with medium to high yield. The study of catalytic activities showed that the heterogenization of guanidine significantly promotes catalytic performance in comparison with guanidine in a homogeneous form. The heterogeneous catalyst is stable in the reaction medium and can be recycled for at least four times without significant reduction in activity. The stability of the catalyst was also investigated by XRD, FTIR, SEM/elemental mapping, and leaching test.

The aim of present investigation is the synthesis of mesoporous catalyst based on hexagonal mesoporous silica. HMS support has exceptional properties such as easy synthesis, high surface area, large pore volume and wormhole pores. These distinctive characteristics beseem use of it as a support for synthesis of heterogeneous catalyst. With functionalization of HMS and immobilization of Zr-rhodanine complex into functionalized HMS, HMS/Pr-Rh-Zr was obtained. New synthesized catalyst (HMS/Pr-Rh-Zr) characterized by FT-IR, XRD, TGA, SEM, EDX, adsorption–desorption of nitrogen at 77 K and ICP techniques. These techniques confirmed that the heterogeneous catalyst of HMS/Pr-Rh-Zr was successfully synthesized. Also the catalytic activity of HMS/Pr-Rh-Zr is investigated for the synthesis of tetrahydrobenzo[b]pyran derivatives from reaction between aldehyde, malononitrile, dimedone in PEG at 80 °C and synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives from reaction between aldehyde, ethyl acetoacetate, malononitrile and hydrazine hydrate in H2O:EtOH at 35 °C. These results confirmed the HMS/Pr-Rh-Zr exhibited good catalytic performance. Furthermore, the synthesized heterogeneous catalyst could be recovered after the reaction and reused several times without any noticeable loss in activity. Also zirconium leaching of HMS/Pr-Rh-Zr was studied whereupon metal leaching of the catalyst was very low.

In this article, a mild and highly efficacious synthetic route has been developed for the synthesis of spiro[indoline-3,9′-xanthene]trione and spiro[chromene-4,3′-indoline]-3-carbonitrile derivatives using graphene oxide-supported dicationic ionic liquid (DIL@GO) as a heterogeneous catalyst in aqueous media. Targeted spiro[indoline-3,9′-xanthene]trione derivatives were synthesized via one-pot condensation of substituted isatins and 1,3-diketone compounds (1,3-cyclohexanedione/dimedone), and spiro[chromene-4,3′-indoline]-3-carbonitrile derivatives were synthesized via one-pot reaction of substituted isatins, malononitrile, and enolizable C-H-activated compounds (2-hydroxynaphthalene-1,4-dione/dimedone). The DIL@GO catalyst demonstrated outstanding catalytic capabilities in all the tested reactions and yielded excellent isolated yields of the final products within a short reaction time. Additionally, the heterogeneous nature of the catalyst facilitates catalyst separation through centrifugation, and its reusability up to five successive reaction cycles with retention in activity makes this methodology more advantageous and environmentally benign.

Regarding the significance of medicinal and pharmacological sciences, we explored one-pot multicomponent reaction of aromatic aldehydes, aryl amines, malononitrile and dimedone in the presence of HMTA-BAIL@MIL-101 (Cr) as a novel, stable and strong catalyst. The remarkable features of this approach are good to excellent yields (92–98%), short reaction times (10–20 min), low catalyst loading, reusability and stability of the catalyst. The prepared hexamethylenetetramine-based ionic liquid/MIL-101(Cr) composite was identified via FE-SEM, XRD, EDS, TGA, BET and FT-IR techniques.

In this work, the novel pistachio hull-OSO3H catalyst was synthesized via preparing pistachio hull as a support followed by treatment with chlorosulfonic acid (ClSO3H) and identified by Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), X-ray diffraction spectroscopy (EDX), Thermogravimetric analysis (TG) and X-ray powder diffraction (XRD). The size of the pistachio hull-OSO3H nanocatalyst was shown by a scanning electron microscope below 100 nm. The catalytic activity of the solid acid catalyst has been successfully examined in a one-pot, three-component condensation reaction of aromatic aldehydes, dimedone and kojic acid under solvent-free condition to furnish dihydropyrano [3,2-b] chromen dione derivatives. The proposed approach has some advantages as excellent yields, mild reaction conditions, short reaction times, use of agricultural waste and eco-friendly nature.

In the present protocol, biogenic synthesis of ZnO nanoparticles using an aqueous extract of weed, i.e. Parthenium is efficiently carried out. The proficient and operationally simple catalytic application of biogenic ZnO nanoparticle is explored towards a synthesis of pharmaceutically relevant and densely functionalized polyhydroquinolines by condensation of four components viz. aromatic aldehyde, dimedone, ethyl acetoacetate, and ammonium acetate. The synthesized polyhydroquinolines were screened for their antimicrobial activity against bacteria and fungi; some of them exhibit better to excellent activity. The developed protocol is enriched with captivating advantages such as excellent yields, shorter reaction time, recyclable catalyst and constructive use of an aqueous extract of Parthenium for the synthesis of ZnO nanoparticle.

Simple and green procedure was developed for the synthesis of various xanthene and coumarin derivatives using beta-cyclodextrin (β-CD) as reusable catalyst at 70 °C in water. Condensation of salicylaldehyde (1 mmol) and dimedone (2 mmol) or 1,3 cyclohexadione (2 mmol) gave corresponding xanthene derivatives, while condensation of salicylaldehyde (1 mmol) with Meldrum’s acid (1 mmol) or 4-Hydroxy-6-methyl-2H-pyran-2-one (1 mmol) gave respective coumarin derivatives in impressive yields. Involvement of β-CD as catalyst was ascertained by inclusion complex evaluation of β-CD-salicylaldehyde with 1H NMR analysis at 70 °C.

A novel efficiently mixed transition metal oxides catalytic system with high catalytic activity and heterogeneity constructed of copper and zinc oxide nanoparticles is presented. For preparation of this hybrid catalytic system, carrageenan as a natural polymeric matrix has been chosen to add biocompatibility to the heterogeneous catalyst. Then, the carrageenan textures have been magnetized through the composition with iron oxide nanoparticles. Copper and zinc metallic sites are employed as the main catalytic sites for catalyzing the synthesis of xanthenedione pharmaceutical derivatives from aldehyde and dimedone. Due to the magnetic behavior of the catalyst, the purification process is carried out with high convenience. Herein, a plausible mechanism for the catalytic process is suggested and reusability of the presented catalyst is also investigated. In this report, it has been well-proven that high reaction yields are obtained for xanthenedione derivatives under mild conditions, through applying the presented hybrid catalytic system.

According to the Food and Agriculture Organization (FAO), Iran is the largest pistachio (Pistacia vera) producer in the world. Nevertheless, pistachio by-products (PBs) contain a high level of phenolic and cellulose compounds, it can be used as a substrate for the preparation of solid acid catalysts. In this work, the novel pistachio hull-OxTiCl4 − x catalyst was synthesized via preparing pistachio hull, product of Kerman, as a support followed by treatment with titanium tetrachloride (TiCl4) and identified by Fourier transform infrared spectroscopy, field emission scanning electron microscopy (FE-SEM), X-ray diffraction spectroscopy (EDX), thermogravimetric analysis (TG), Brunauer–Emmett–Teller (BET) and X-ray powder diffraction (XRD). The size of the nano-pistachio hull-OxTiCl4 − x nanocatalyst was shown by a scanning electron microscope below 100 nm. The catalytic activity of the solid acid catalyst has been successfully examined in a one-pot, three-component condensation reaction of aromatic aldehydes, dimedone and kojic acid in refluxing ethanol to furnish dihydropyrano[3,2-b]chromendione derivatives. Consequently, pyran annulated heterocycles were obtained. The proposed approach has some advantages as excellent yields, mild reaction conditions, short reaction times, use of agricultural waste and eco-friendly.

Chitosan functionalized by triacid imide has been applied as an effective catalyst for the synthesis of benzodiazepines by one-pot reactions of 1,2-phenylenediamine with dimedone and aryl aldehydes or isocyanides and Meldrum’s acid. Chitosan functionalized by triacid imide was confirmed by FT-IR (infrared spectroscopy), XRD (X-ray diffraction), DSC (differential scanning calorimetry) and TGA (thermogravimetric analysis). To investigate the scope and limitation of this reaction, different aryl aldehydes and isocyanides were used as substrates. Good yields in short reaction times, experimental simplicity, extensive range of products, retrieval of the catalyst and low catalyst loading are some of the substantial aspects of this method.

Spinel-type oxide MgMnO3 and perovskite-type oxide SrMnO3 have been synthesized by two-step procedures comprising the hydrothermal and solid-state methods. The as-prepared catalysts were characterized by X-ray powder diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis and the morphologies of the synthesized materials were figured out by field emission scanning electron microscopy. The catalytic performance of synthesized materials were investigated by synthesizing the polyhydroquinolines, which was used Design-Expert software and response surface methodology (central composite design) for optimization of reaction efficiently. The comparison study illustrates that MgMnO3 has better catalytic performance than SrMnO3 and optimized condition for the synthesis of polyhydroquinoline (which is produced by the reaction of ethyl acetoacetate, benzaldehyde, dimedone and ammonium acetate) was found to be 8 mg of MgMnO3 as the catalyst, 33 min for the reaction time and 100 °C for the reaction temperature. This condition was used for the synthesis of other polyhydroquinoline derivatives.

Novel unsaturated piperazine and homopiperazine derivatives (3a–h) were synthesized in medium to good yields by acylation reactions of piperazine and homopiperazine with methacrylic anhydride (2a) and benzoyl chloride (2b). Piperazine containing dihydrofuran compounds (5a–l) were obtained from radical addition and cyclizations of 3a–h with 1,3-dicarbonyl compounds such as dimedone (4a), ethyl acetoacetate (4b) and acetylacetone (4c) mediated by Mn(OAc)3 for the first time. While the reaction of 3b (1-methacryloylpiperazine) with 4a and 4b gave bis-dihydrofurans (5b and 5d) beside mono-dihydrofurans (5a and 5c), the reaction of 3b–e, 3g, 3h, and 3e with 1,3-dicarbonyl compounds gave mono dihydrofuran compounds (5f–l) in medium to high yields. Structures of all novel compounds were determined by melting point analysis, 1H NMR, 13C NMR, HRMS, and FTIR methods. All piperazine containing dihydrofuran compounds were evaluated for their inhibitory activities toward acetylcholinesterase (AChE) by Ellman method and IC50 values were presented. Compounds 5c, 5d, 5e, 5i, and 5l show highest inhibitory activities with IC50 values of 5.79, 3.89, 5.07, 4.30, and 2.24 µM, respectively. In addition, molecular docking studies were performed on selected structures 5d, 5i, and 5l to investigate ligand–protein interactions. Binding energies were calculated and compared with standart drug donepezil.

We are aiming in this work to synthesize target molecules not only possess antitumor activities but also kinase inhibitors. The target molecules were obtained from dimedone, which reacted with triethoxymethane to produce a product that is capable for many heterocyclization reactions to give fused pyrazole, thiophene and isoxazole derivatives. Compounds 7b, 7c, 7d, 9b, 11, 12c, 12d, 14b, 16b, 17c, 17d, 18c, 18d, and 18e were the most cytotoxic compounds, their further tests toward the five tyrosine kinases c-Kit, Flt-3, VEGFR-2, EGFR, and PDGFR and Pim-1 kinase showed that compounds 7b, 7d, 11, 12c, 14b, 16b, 17d, 18d, and 18e were the most potent of the tested compounds toward the five tyrosine kinases and compounds 7b, 7d, 14b, 16b, and 18e were of the highest inhibitions toward Pim-1 kinase. PAINS the most cytotoxic compounds showed zero PAINS alert, therefore, these compounds can be used as useful drugs in the future.

Simple synthesis of oxoquinoline carboxamide derivatives via one-pot, multi-component reaction of enaminones derived from the addition of dimedone to various anilines with aromatic aldehydes and cyanoacetamide is described. Optimal reaction conditions for the synthesis of products were obtained, when EtOH/H2O (1:1) was used as the solvent at 80 °C, in the presence of piperidine as the catalyst. The reactions are completed within 5–25 min, in good to high yields (74–85%). This protocol involves Michael reaction, imine-enamine tautomerization, and cyclization sequences. The structures of products were deduced from their IR, mass, 1H NMR, and 13C NMR spectra. This method includes some important aspects including simple operation under mild conditions, easy accessibility of reactants, workup procedure, high atom economy, and the use of ethanol/water as a green media.

In this study, a novel acid-functionalized magnetic nanoparticles with high loaded multifunctional acidic groups was fabricated by anchoring water-soluble 5-sulfosalicylic acid onto the surface silica-modified Fe3O4. The magnetically recyclable Fe3O4@SiO2@5-SA (20 mg) showed excellent reactivity for greener synthesis of tetrahydrobenzo[b]pyrans via a three-component reaction of different aromatic aldehydes, malononitrile and dimedone in good to excellent yields (70–95%) in pure water at short reaction times (40–150 min). The method shows eco-friendly synthesis of quinoxaline derivatives from direct condensation of substituted 1,2-diamine with various 1,2-dicarbonyl in ethanol at room temperature to afford the desired quinoxalines with good to excellent yields (60–97%) at shorter reaction times (120–240 min). The morphology and magnetic properties of MNPs were studied with scanning electron microscopy, X-ray powder diffraction, Fourier translation infrared spectroscopy, vibrating sample magnetometer and thermogravimetric. The results showed that the Fe3O4@SiO2@5-SA catalyst is completely recoverable by an external magnet and retained catalytic activity after five recycles.

Bisulfate-functionalized dicationic ionic liquid grafted with silica-coated nano-Fe3O4 (nano-[Fe3O4@SiO2@BDIL] or NFSBDI) was synthesized as a novel nanomagnetic material, and its structure was confirmed by EDS, FE-SEM, FT-IR, VSM, XRD and TGA. Afterward, it was utilized as an efficient, magnetically recyclable and dual-functional catalyst for the preparation of an important class of uracil-containing heterocycles, namely pyrimido[4,5-b]quinolines. The one-pot multicomponent reaction of dimedone, arylaldehydes and 6-amino-1,3-dimethyluracil in the presence of NFSBDI under solvent-free conditions afforded pyrimido[4,5-b]quinolines in high yields and short times.

The present work reports a catalytic application of aluminized polyborate for the solvent-free one pot four-component green, efficient and cost-effective synthesis of polydroquinoline derivatives. The aluminized polyborate was synthesized from readily available non-toxic, inexpensive boric acid and aluminium trichloride and characterized by IR, XRD, SEM and EDAX techniques. The polyhydroquinolines were successfully synthesized by well-known Hantzsch condensation reaction of differently substituted aldehydes, dimedone, ethylacetoacetate and NH4OAc at 100 °C under solvent-free condition. The catalyst is stable and easy to use with some significant features such as good acidic catalytic activity, inexpensive and eco-friendly nature. Along with this, excellent product yields, short reaction time, clean reaction, operational simplicity, solvent-free condition and non-column purification are some more additional aspects of this protocol.

An efficient and simple method for the synthesis of xanthene derivatives by using iron oxide nanoparticles (NPs) as a catalyst has been investigated. Synthesis of 9-substituted xanthene-1,8-dione derivatives involves one-pot reaction of dimedone and aldehyde in the presence of iron oxide nanoparticles using polar protic ethanol as a solvent. Interestingly, this catalyst has been recovered by simple filtration and reused for up to five cycles without much loss of its productivity. The merits of this protocol are cost-effectiveness of the catalyst, having no harmful side products, simple process, short reaction time, convenient product isolation and potential yields.

A novel nanomagnetic catalyst has been synthesized by immobilization of triethanolamine lactate cellulose with Fe3O4 NPs. The prepared catalyst has been used as an efficient and recoverable catalyst for the regioselective synthesis of pyrazolo quinolones by the three-component reaction of dimedone, 5-amino pyrazolone and aromatic aldehydes in ultrasound condition. This economical catalyst provides high yields of products, short experimental time and easy workup for green synthesis of pyrazolo[3,4-b]quinolone compounds. Theoretical studies have been employed to investigate the reaction mechanism by using the B3LYP/6-311G method. Electronic parameters of all components have been determined in order to reorganize the role of components in the reaction mechanism.

Cinchonine-catalyzed simple, expeditious, and efficient protocol for the synthesis of quinoline-based 4H-pyran and tetrahydro-4H-chromenes has been demonstrated via one-pot domino Knoevenagel–Michael cyclocondensation reaction of aromatic aldehyde, active methylene compound and activated C–H acids like alkylacetoacetates/dimedone in ethanol under reflux. This protocol enables a rapid construction of diverse range of 4H-pyran and tetrahydro-4H-chromene derivatives from readily available starting materials. Short reaction time, mild reaction conditions, broad substrate scope, high yields, metal-free approach, and purification without column chromatography are notable features of this methodology.

In this work, the novel approach via propylphosphonic anhydride (T3P®)-promoted synthesis of 1,5-benzodiazepines from o-phenylene-diamine, 5,5-dimethylcyclohexane-1,3-dione (dimedone), and aromatic aldehydes has been studied. The reaction conditions were optimized and the scope of the reaction was extended to various aromatic aldehydes. The synthesized compounds were obtained in reasonable to good yields.

The three-component Hantzsch condensation of various aryl aldehydes, dimedone, and methyl 3-aminocrotonate was investigated in the presence of MCM-41-supported ZnNO3. The polyhydroquinoline products which were obtained under mild conditions and very easy workup were evaluated for anti-cancer activities against MCF-7, SK-BR-3, and HT-29 of breast and colon cancer cells. The fluorescence emission of some products was also studied and their optical parameters were reported.

In the present study, we demonstrated the synthesis of magnetic cyanoguanidine-modified chitosan (MCGC) as an efficient and green retrievable heterogeneous nanocatalyst for one-pot three-component synthesis of benzimidazoloquinazolines (from 2-aminobenzimidazole, aromatic aldehydes, and dimedone) and 1,4-dihydropyridines (via Hantzsch-type condensation of ethyl acetoacetate, aromatic aldehydes, and ammonium acetate) under the ultrasonic irradiation and reflux conditions. The structure of the catalyst was fully confirmed using Fourier transform infrared spectroscopy, vibrating sample magnetometer, field emission scanning electron microscopy, energy dispersive spectroscopy, and thermogravimetric analysis. Increased amount of amino groups that are generated by modifying the surface of chitosan with cyanoguanidine as well as presence of hydroxyl groups determined the catalytic activity of MCGC. Furthermore, as experimental results confirmed, the ultrasonic-promoted reactions gave the better results in terms of reaction time, yield, and purity of isolated products. Cost effectiveness, mild conditions, low catalyst loading, convenient work-up, and ecofriendly solvent are some of the remarkable advantages of this protocol.

A series of novel fused pyrrole derivatives was synthesized by one-pot three-component reaction of β-enaminoketones, derived from cyclohexane-1,3-dione or dimedone, arylglyoxal hydrates, and 1,3-dimethylbarbituric acid in EtOH.

For the first time the catalytic activity of AgNdSiW11, was examined in two named reactions, namely Hantzsch and Biginelli reactions. A simple, eco-friendly and highly efficient one-pot synthesis of polyhydroquinoline derivatives via Hantzsch multicomponent reactions (MCRs) involving cyclocondensation of differently-substituted aldehydes, β-ketoesters or dimedone, active methylene compounds, and ammonium acetate as a source of nitrogen, in the presence of AgNdSiW11 as a catalyst in EtOH/H2O under reflux conditions in high yields was successfully achieved. Furthermore, the catalytic performance of AgNdSiW11 was also successfully tested in the synthesis of 3,4-dihydropyrimidin-2-(1H)-ones via Biginelli MCR involving cyclocondensation of differently-substituted aldehydes, ethyl acetoacetate and urea as source of nitrogen in the presence of AgNdSiW11 under reflux conditions in EtOH/H2O. This prolific combination of Ln and POMs inaugurates a powerful class of catalysts for the different chemical transformations, which overcomes key limitations of previously established salts and Lewis acidic metals-based catalysts under low catalyst loading, the use of water scavengers, dry solvents and additives for facilitating the specialized experimental setups commonly employed to the organic reactions.

A simple and efficient one-pot process for the synthesis of 1,8-dioxo-octahydroxanthene and 2,2′-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives via the Knoevenagel–Michael cascade reactions of aromatic aldehydes and dimedone catalyzed by Bronsted acidic ionic liquids (BAILs) in solvent-free and aqueous conditions is described in this study. These heterocycles were prepared in the presence of Bronsted acidic ionic liquids as a suitable, economical, readily synthesized and eco-friendly catalyst. This method offers several advantages such as high yields, simplicity of the workup, low cost, short reaction times, green conditions and use of a reusable catalyst.

A facile, convenient, and efficient synthesis of new chromeno[4,3-b]quinoline and chromeno[4,3-b]pyridine derivatives has been accomplished via one-pot three-component reaction of 4-aminocoumarin, 1,3-dicarbonyl compounds (dimedone and Meldrum's acid), and substituted aromatic aldehydes in H2O or EtOH under reflux conditions using 10 mol % of guanidine hydrochloride as organocatalyst. Formation of products proceeds through tandem Knoevenagel and Michael reactions, followed by concomitant cyclization and dehydration or decarboxylation. A wide range of aromatic aldehydes were tolerated by the developed protocol. The advantages of this environmentally friendly synthetic approach are short reaction times, high atom economy, operational simplicity, application of readily available catalyst, z high yields of products, simple workup procedure, and possibility to purify products by recrystallization.

In this study, several new 12-aryl/heteroaryl-3,3-dimethyl-tetrahydrobenzo[b]acridine-1,6,11(2H)-trione heterocyclic compounds that can be considered as 1,4-naphthoquinone fused with 4-substituted 7,7-dimethyl-4,6,7,8-tetrahydroquinolin-5(1H)-ones, have been synthesized through the three-component cyclocondensation of benzaldehydes/heteroaldehydes, 2-amino-1,4-naphthoquinone, and dimedone. The pot-, atom-, and step-economy reactions were implemented under reflux conditions. One of the most important aspects of this reaction is the use of ethanol as the reaction medium taking into account the principles of green chemistry. Not using a catalyst in this type of reactions is also significant from the standpoint of green chemistry. The protocol developed in this study has the benefits of the simplicity, no use of chromatographic methods for purification, structural diversity, employing non-toxic solvent, good-to-high yields, safety, and using cost-effective solvent. The structures of the newly synthesized 1,4-naphthoquinone fused with 4-substituted 7,7-dimethyl-4,6,7,8-tetrahydroquinolin-5(1H)-ones were confirmed employing spectroscopic data as well as elemental analysis.

In this study, the MgFe2O4 nanoparticles were synthesized via a green and simple approach. Then an effective procedure to synthesize 2-amino-7-hydroxy-4H-chromene and tetrahydrobenzo[b]pyran derivatives was established through the chemical reaction between different aldehydes, malononitrile and resorcinol (or dimedone) in the presence of MgFe2O4 nanoparticles as a beneficial catalyst in ethanol as solvent under ultrasound irradiation. Moreover, the synthesized MgFe2O4 nanoparticles were easily recovered by an external magnet and reused for four times without significant loss of their catalytic activity. Simple, fast, effective and eco-friendly as well as quick purification method along with high product yields are some of the advantages of the present chemical reaction.

Sulfonated Sulfurol supported Fe3O4 (Fe3O4@SiO2-Pr-Sulfurol-SO3H) a new magnetic reusable nanocatalyst was prepared using chemical modification of magnetic nanoparticles (MNPs) surface with Sulfurol-SO3H. The Sulfurol-SO3H moieties on the surface of MNPs act as acidic catalytic sites for catalysis purposes. Fe3O4@SiO2-Pr-Sulfurol-SO3H was authenticated by usual analytical and spectroscopic techniques. The prepared Fe3O4@SiO2-Pr-Sulfurol-SO3H MNPs were applied to the preparation of novel Spiro[acridine-9,5′-thiazole]-1,4′-dione derivatives via the three-component condensation of isatins, dimedone and thioamides or thioureas.

One pot synthesis of “Schiff” base is carried out in this study. The synthesis by using microwave reaction as a modern method is realized from 4-dimehtylamino-5,5-dimethyl-1,3-cyclohexanedione, benzene 1.4-diamine and 1,3-benzodioxole-5-carbaldehyde. The structural properties of the resulting compound were determined by NMR (1H and 13C), low-resolution mass spectrometry (ESI–MS), FTIR spectroscopy and x-ray diffraction. The product is semicrystalline material with a monoclinic unit cell. Based on the optical spectra, the compound has an optical band gap of (Eg = 2.89 eV). In addition, the dielectric spectroscopy was applied for studying the ac-electrical conductivity, dielectric constant and dielectric losses of the synthesized “Schiff” base. The results obtained from this study show that it has a promising future in the field of organic optoelectronics and their potential applications especially in photovoltaic conversion energies.

This study aims to use a new medicinal porous plant having a high content of silica known as horsetail and horsetail ash for the first time as novel, efficient, and environmentally friendly natural mild catalysts. The structure of these catalysts was characterized by different techniques such as FT-IR, XRF, SEM–EDS, N2 adsorption–desorption, XRD, and ICP analysis. The results obtained from the analysis revealed that both horsetail and horsetail ash could act as a solid acid catalyst. In addition, a further detailed analysis illustrated that they have a different surface area, porosity, and crystalline structure which can affect their catalytic activities. The synthesis of 2-amino-4H-chromene derivatives was performed via a one-pot three-component condensation of dimedone, malononitrile, and various aromatic aldehydes to compare their catalytic activities under solvent-free conditions. Due to its high porosity and high surface area, horsetail ash yields better results compared to the horsetail itself. FT-IR, mass, 1H-NMR, and 13C-NMR spectroscopies were used to identify the synthesized compounds in this study. An important advantage of this method is the use of these effective natural catalytic systems with characteristics such as low cost, mild reaction conditions, nontoxicity, and reusability which resulted in corresponding products in high to excellent yields and proper reaction times.

NiO@g-C3N4 as an efficient catalyst for the synthesis of spirooxindole derivatives was prepared by impregnation of g-C3N4 with NiO nanoparticles and characterized by various techniques including thermogravimetric analysis, transmission electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy. The one-pot synthesis of spirooxindole derivatives using 1 mmol isatin, 1 mmol dimedone (or 4-hydroxycoumarin or ethyl acetoacetate) and 1 mmol malononitrile was carried out in the presence of 50 mg NiO@g-C3N4 in EtOH media at reflux conditions. The results showed that both series of reactions had short reaction times (less than 7 min) and high reaction efficiency (greater than 87%). Some advantages can be cited for this method, including short reaction time, excellent yields, easy workup and a reusable and inexpensive nanocatalyst.

An efficient, straightforward and rapid method has been developed for the synthesis of tetrahydrobenzo[α] xanthen-11-one using sodium acetate. The reaction was performed via three components: β-naphthol, dimedone with various aromatic aldehydes under solvent-free microwave irradiation and conventional heating condition. We observed an efficient result for microwave synthesis than conventional heating. The synthesized tetrahydrobenzo[α]xanthen-11-one (4a–l) was screened for their antimicrobial activity against two bacteria (Escherichia coli and Bacillus subtilis) and two fungal strains (Aspergillus niger and Saccharomyces cerevisiae). The synthesized products: 9, 10-dihydro-9, 9-dimethyl-12-(4-nitrophenyl)-8H-benzo[a]xanthen-11(12H)-one, 9, 10-dihydro-9, 9-dimethyl-12-(2, 4-dichlorophenyl)-8H-benzo[a]xanthen-11(12H)-one, 9, 10-dihydro-9, 9-dimethyl-12-(6-methyl-4-oxo-4H-chromen-3-yl)-8H-benzo[a]xanthen-11(12H)-one exhibit good antimicrobial activity. The developed protocol is graced with appealing advantages such as high purity, simple operation, excellent yields, inexpensive and easy availability of catalyst.

An economical and proficient approach has been developed for the synthesis of chromenopyrimidines via three-component reaction of thiobarbituric acid/barbituric acid, methylarenes and dimedone/1,3-cyclohexanedione by using lemon juice as a natural, biodegradable catalyst and TBHP as an oxidant. This transformation involves metal-free C-C bond formation via C-H activation of methylarenes under mild reaction conditions.

In this abstract, we discuss the progress related to sulfonated carbon-based materials in various acid-catalyzed organic transformations which are then further utilized in medicinal field, laboratories and industries. A simple and novel methodology was employed to prepare carbon-based nanocatalyst, i.e. cellulose[2-(sulfooxy)ethyl]mercaptosulfonic acid as a solid acid catalyst. This nanocatalyst is recyclable and also exhibited very high activity. Novel carbon-based nanocatalyst, i.e. cellulose[2-(sulfooxy)ethyl]mercaptosulfonic acid[SEMSA] was successfully synthesized by reacting mercaptoethanol and chlorosulfonic acid, and the catalytic activity of the prepared catalysts was evaluated for the one-pot synthesis of gem-bisamides from various aldehydes and benzamide, hexahydroacridine-1,8-diones via three-component condensation of aromatic aldehyde, dimedone and ammonium acetate or aromatic amine and 1,8-dioxo-octahydroxanthenes using aldehyde and dimedone. Application of this new heterogeneous nanocatalyst system offered the advantages of high yields, short reaction times, eco-friendly nature and easy work-up procedure compared to the conventional methods of the synthesis, and confirmation of products synthesized has been done using studies like 1H NMR and 13C NMR. Among the various catalysts, this nanocatalyst, i.e. cellulose [2-(sulfooxy)ethyl]mercaptosulfonic acid[SEMSA], was found to be the most active and selective and could be recycled several times without significant loss of activity. Also, scanning electron microscopy and transmission electron microscopy of the catalyst have been performed to know the internal and external morphology, size, thermo-gravimetric analysis to study the thermal stability and Fourier transform infrared spectroscopy to study the modification pattern of the catalyst have been undertaken and presented in this work. Due to its simple and inexpensive solid support, i.e. cellulose and environmentally benign toluene, ethanol and acetonitrile as solvents in three different transformations which are less toxic, easily available and less expensive than other solvents. We reported here a novel route for the synthesis of gem-bisamides, hexahydroacridine-1,8-diones and 1,8-dioxo-octahydroxanthenes

A novel heteropolyanion-based Bronsted acidic ionic liquid material [PhBS]3PW12O40, butane mono-sulfoacid-functionalized phenanthrolinum salt of phosphortungstate catalyst (PhBS-PW), was synthesized and well characterized with FTIR, 1H and 13C NMR, electro-spray ionization mass spectrometry (ESI-MS), EDX and TG analysis techniques. The new prepared catalyst was used for the efficient one-pot synthesis of 2H-indazolo[2,1-b]phthalazine-trione derivatives from a three-component condensation reaction between aromatic aldehydes, dimedone, and phthalhydrazide in H2O under thermal conditions. This green approach has several advantages such as short reaction times, clean reaction profiles, and simple experimental and workup procedures. Moreover, the catalyst can be easily recovered and reused at least nine times with only slight reduction in its catalytic activity with no leaching amount of catalyst into the reaction mixture. These economical factors (time, cost, waste, etc.) for this three-component reaction hold promise for the future of organic synthesis. In this work we introduced a new efficient Bronsted acidic ionic liquid (BAIL) and then its catalytic activities have been considered in the three-component synthesis of 2H-indazolo[2,1-b]phthalazine-triones via the domino Knoevenagel condensation/Michael addition/intramolecular cyclodehydration sequence in water under reflux condition.

An efficient and highly selective protocol for the production of 10,11-dihydrochromeno[4,3-b]chromene-6,8(7H,9H)-dione derivatives has been developed. The one-pot multi-component condensation of arylaldehydes with 4-hydroxycoumarin and dimedone in the presence of a mesoporous acidic nanocatalyst, namely nano-N,N,N′,N′-tetramethyl-N-(silica-n-propyl)-N′-sulfo-ethane-1,2-diaminium chloride (nano-[TSPSED][Cl]2) selectively afforded the mentioned compounds in high yields and in relatively short reaction times. The nanocatalyst was reusable for four times without significant loss of activity. Our catalyst was better than the reported catalysts in terms of three or more of these factors: the reaction temperatures, times, yields, turnover number and turnover frequency.

A series of 9-aryl-hexahydroacridine-1,8-diones are synthetized with good to excellent yields (50–99%) via a one-pot four-component reaction of dimedone, aromatic aldehydes and ammonium acetate in the presence of 4 A molecular sieves modified with iron(III) as an efficient heterogeneous catalyst, in ethanol. The process offers the advantages of high yields, mild reaction conditions and easy work-up procedure. The catalyst can be reused without significant loss of activity.

Chloroacetic acid immobilized on chitosan (CS) coated iron oxide decorated by silver nanoparticles (Fe3O4@CS@Ag@CH2COOH) was synthesized as a biocompatible magnetic material. The Fe3O4@CS@Ag@CH2COOH nanocomposite was characterized using FT-IR, XRD, SEM, EDS, and TGA instruments. The surface morphology and size of Fe3O4@CS@Ag@CH2COOH nanocomposite were determined through SEM micrographs analysis. Moreover, magnetic characterization of the prepared nanocomposite was determined by VSM. The produced Fe3O4@CS@Ag and Fe3O4@CS@Ag@CH2COOH nanocomposites were screened for their antibacterial activity against gram-negative Escherichia coli and gram-positive Staphylococcus aureus. The results showed that the Fe3O4@CS@Ag and Fe3O4@CS@Ag@CH2COOH nanocomposites presented good antibacterial performance toward gram-negative Escherichia coli and gram-positive S. aureus. Furthermore, Fe3O4@CS@Ag@CH2COOH nanoparticles catalyzed one-pot synthesis of hexahydroquinoline-3-carboxamide derivatives by four-component reaction of arylaldehydes, dimedone, acetoacetanilide and ammonium acetate in ethanol at 70 °C.

Pentaerythritol was applied as an effective, biodegradable, nontoxic, mild, and commercially available H-bonding organocatalyst for synthesis of indazolo[2,1-b]phthalazine-trione derivatives via one-pot three-component condensation of aromatic aldehydes, phthalhydrazide, and dimedone under thermal solvent-free conditions in high to excellent yield.

A regioselective three-component reaction of α,β-unsaturated aldehydes, cyclic 1,3-dicarbonyls and 6-aminouracils in the presence of FeCl3·6H2O as catalyst under microwave irradiation has been demonstrated. Three-component reaction of α,β-unsaturated aldehydes like cinnamaldehyde/crotonaldehyde, cyclic 1,3-diketones such as 2-hydroxy-1,4-naphthaquinone/dimedone and 6-aminouracils provides regioselective pyrimidine-fused tetrahydropyridines tethered with cyclic 1,3-diketones. On the other hand, replacing cyclic 1,3-diketones by 4-hydroxycoumarin and keeping all other conditions the same provided a two-component pyrimidine-fused pyridines. The salient features of this methodology are operational simplicity, short reaction time, good-to-moderate yields of the products, easy purification method and regioselective products having medicinally important heterocyclic rings such as pyrimidine, tetrahydropyridine or pyridine.