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AbstractA nickel ferrite nanocatalyst was synthesized in the presence of simple and cost-effective polysorbates assisted sol gel method as an effective catalyst has been successfully used for one pot multicomponent Hantzsch condensation reaction of different aromatic aldehydes, dimedone and ammonium acetate under solvent-free condition at 110 °C-120 °C. The highlights feature for the synthesis of acridinediones are the recyclability of catalyst, solvent-free reaction condition, use of inexpensive catalyst, highly efficient, facile product isolation, clean reaction, nontoxic substances and great yields in short reaction time. The recovered catalyst can run four times without loss its activity. [ABSTRACT FROM AUTHOR]

A novel heterogeneous pumice supported perchloric acid catalyzed synthesis of tetrahydrobenzo[b]pyran has developed via multi-component condensation of aromatic aldehydes, dimedone and malononitrile. The catalyst was characterized by IR, XRD, EDS, SEM, and TGA techniques which confirmed the formation novel pumice supported perchloric acid. The present protocol proved to have numerous advantages like one-pot reaction, good yield, short reaction time, inexpensive catalyst, recyclability and reusability of the catalyst, simple experimental and work up procedure, and purification of targeted molecules without column chromatography. [ABSTRACT FROM AUTHOR]

In this work, Fe3O4@nano-walnut shell/BIII (FNWSB), as a reusable and new catalyst was prepared and then characterized by FT-IR, XRD, FESEM, EDS-MAP, and TGA. This catalyst was used for synthesis of tetrahydrobenzo[a]xanthen-11-ones via three-component, one-pot condensation reaction of dimedone, β-naphthol, and aromatic aldehydes. An uncomplicated work-up, high yields of product, short reaction times, and use of low-cost catalyst are considerable advantages of this procedure. [ABSTRACT FROM AUTHOR]

A simple microwave assisted tungstophosphoric acid (H3PW12O40) catalyzed protocol was employed for the synthesis of versatile enaminoketones. The developed synthetic procedure is green, efficient and environmentally benign. Using this method, a series of enaminoketones were prepared from the condensation of dimedone and various amines. Further, the synthesized enaminoketones were evaluated for in-vitro anti-inflammatory activity by membrane stabilization method and anti-oxidant efficacy by radical scavenging method. The synthesized enaminoketones 3c, 3b and 3b, 3f showed reasonable anti-inflammatory as well as anti-oxidant activities respectively. [ABSTRACT FROM AUTHOR]

This work represents a simple and efficient synthesis of novel 2-amino-N'-(9H-fluoren-9-ylidene)-hexahydroquinoline-3-carbohydrazide derivatives via the multi-component reaction of diverse anilines, dimedone, 9-fluorenone, cyanoacetohydrazide, and aromatic aldehydes in the presence of piperidine as a catalyst. The proposed approach has some advantages as good yields, green medium, short reaction times, simple work-up, and purification process with no chromatographic technique compared with other methods. Supplemental data for this article is available online at at the publisher's website. [ABSTRACT FROM AUTHOR]

In this study, the domino Knoevenagel-Michael and cyclization reaction between 5,5-dimethyl-1,3-cyclohexanedione (dimedone) and aryl aldehydes was performed in the presence of sulfacetamide as an organocatalyst in refluxing ethanol for the synthesis of 3,3,6,6-tetramethyl-9-aryl-1,8-dioxo-octahydroxanthene derivatives. This organocatalyzed reaction proceeds through the formation of 2,2′-[(4-(aryl)phenyl)methylene]bis[3-hydroxy-5,5-dimethylcyclohex-2-en-1-one] intermediates, leading to the construction of final oxygen-containing heterocyclic compounds. Considering the loading of the organocatalyst and the study of the effects of the solvent, it can be concluded that 2 mol% of catalyst and ethanol are the best choice to run the pseudo-three-component reaction. Furthermore, the pot-economy, atom-economy, and step-economy reaction follows some principles of green chemistry, such as cost-effectiveness, benign catalyst, and using nontoxic solvent. [ABSTRACT FROM AUTHOR]

An efficient and green route for the preparation of 1,8-dioxo-decahydroacridines in excellent yields (83%–94%) is described. The products have been synthesized from aromatic aldehydes and 5,5-dimethyl-1,3-cyclohexanedione(dimedone) with amines. Also, four new 1,8-dioxo-decahydroacridine derivatives are presented. The method is very simple and environmentally friendly due to use from glycerol as a promoter and do not use of any harmful organic solvent and catalyst-based transition metal under mild conditions. [ABSTRACT FROM AUTHOR]

A simple, efficient and ecofriendly procedure has been developed for the synthesis of bis(hexahydroacridine-1,8-diones) and bis(tetrahydrodipyrazolo[3,4-b:4′,3′-e]pyridines) derivatives using p-TSA as catalyst under microwave-assisted reaction conditions as well as under conventional heating. [ABSTRACT FROM AUTHOR]

A convenient and high yielding procedure for the synthesis of triazolo[1,2-a]indazole-triones by the condensation reaction between 1,2,4-triazolidine-3,5-dione (urazole), 5,5-dimethylcyclohexane-1,3-dione (dimedone) and aryl aldehydes in the presence of acidic dicationic ionic liquid 1,4-diazabicyclo[2.2.2] octanium diacetate as a highly stable and reusable ecofriendly catalyst under ultrasound irradiation is described. This procedure is simple and successful and offers easy workup, mild condition and excellent yield in a short time. All of the synthesized compounds were characterized by IR, 1H NMR, 13C NMR and elemental analysis. [ABSTRACT FROM AUTHOR]

Several new fused polycyclic 2,3-dihydro-thieno[2,3-b]quinolin-3-ol derivatives were synthesis through the un-catalyzed reaction of various 2-mercaptobenzoquinoline-3-carbaldehydes with 2-bromoacetophenones in CH2Cl2 at 80–90% yield. Besides, reaction of differently substituted 3-formyl-2-mercaptoquinolines and various 1,3-dicarbonyl compounds such as dimedone, ethyl acetoacetate and 1,3-indandione) in the presence of AlCl3 as an efficient catalyst in CH2Cl2 at room temperature gave different novel fused polyheterocycle derivatives depends on the selection of 1,3-dicarbonyl compounds, respectively. [ABSTRACT FROM AUTHOR]

As benzodiazepines occupy an important place in the realm of medicinal and material chemistry, a facile, ecofriendly, one-pot protocol for the synthesis of 4-substituted-1,5-benzodiazepine derivatives has been described through the one-pot three-component reaction of o-phenylenediamine, dimedone, and aldehydes in the presence of tris(hydrogensulfato) boron [B(HSO4)3] under reflux conditions in aqueous ethanol. The operational simplicity without column chromatographic purification and the avoidance of using hazardous and expensive solvents and catalysts are the most advantages of this method. [ABSTRACT FROM AUTHOR]

The general multicomponent approach was found to the medicinally relevant 5-aryl-chromeno[2,3-b]pyridine scaffold. Triethylamine catalyzed multicomponent reaction of benzaldehydes, 2-aminoprop-1-ene-1,1,3-tricarbonitrile and dimedone in a minimal amount of propanol results in efficient formation of substituted 2,4-diamino-8,8-dimethyl-6-oxo-5-aryl-6,7,8,9-tetrahydro-5H-chromeno[2,3-b]pyridine-3-carbonitriles in 75–80% yields. This general and efficient approach avoids traditional recrystallization and chromatographic purification stages and opens a convenient way to scaffolds, promising for many diverse oriented medical applications. [ABSTRACT FROM AUTHOR]

Grafting of SnCl4on the Fe3O4@SiO2nanoparticles afforded Fe3O4@SiO2-SnCl4as a novel inorganic heterogenous catalyst, which was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), vibrating sample magnetometry (VSM), Field Emission Scanning Electron Microscopy (FE-SEM), and transmission electron microscopy (TEM). In this research, we report a convenient and efficient direct protocol for the preparation of xanthene derivatives via condensation of β-naphthol, dimedone, or mixture of β-naphthol and dimedone with various aromatic aldehydes in the presence of the catalytic amount of Fe3O4@SiO2-SnCl4under ultrasonic irradiation. This procedure has a lot of advantages such as: very easy reaction conditions, absence of any tedious workup, or purification, and much milder method. The corresponding products have been obtained in excellent yields, high purity, and short reaction times. [ABSTRACT FROM AUTHOR]