Arylmethylene Bis Research Articles

An eco-friendly approach to synthesize arylmethylene bis(3-hydroxy-5,5’-dimethyl-2-cyclohexene-1-ones) and 1,8-dioxo-octahydroxanthenes

An eco-friendly approach to synthesize arylmethylene bis(3-hydroxy-5,5’-dimethyl-2-cyclohexene-1-ones) and 1,8-dioxo-octahydroxanthenes

Synthesis of 4,4'-(Aryl Methylene)Bis(3-Methyl-1H-Pyrazol-5-ol) Derivatives and Pyrano[2, 3-c] Pyrazole Derivatives Using an Engineered Copper-Based Nano-Magnetic Catalyst (Fe3O4@SiO2/Si(OEt)(CH2)3NH/CC/EDA/Cu(OAc)2)

In this work, Fe3O4@SiO2/Si(OEt)(CH2)3NH/CC/EDA/Cu(OAc)2 as a copper-based nano-magnetic catalyst was prepared and characterized by Energy Dispersive X-ray analysis (EDX) and EDX-Mapping, Field-Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM), Vibrating Sample Magnetometer (VSM), Fourier transform infrared spectroscopy (FT-IR), Thermal Gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA). The catalytic activity of the synthesized catalyst was investigated in the synthesis of 4,4'-(aryl methylene)bis(3-methyl-1H-pyrazol-5-ol)s and pyrano[2,3-c]pyrazoles by the one-pot reactions under solvent-free conditions. Short reaction times, high yields and solvent-free conditions are some benefits of the presented work.

Synthesis of sulfonated melamine-functionalized Fe3O4@SiO2@Si–(CH2)3@melamine nanoparticles and its application in the synthesis of 4,4’-(aryl methylene)bis(3-methyl-1H-pyrazol-5-ol)s and hexahydroquinolines

Synthesis of sulfonated melamine-functionalized Fe3O4@SiO2@Si–(CH2)3@melamine nanoparticles and its application in the synthesis of 4,4’-(aryl methylene)bis(3-methyl-1H-pyrazol-5-ol)s and hexahydroquinolines

Montmorillonite KSF-Catalyzed Synthesis of 2,2′-(Arylmethylene)bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-ones) for the Functionalization of MCM-41 Silica Nanoparticles

Montmorillonite KSF-Catalyzed Synthesis of 2,2′-(Arylmethylene)bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-ones) for the Functionalization of MCM-41 Silica Nanoparticles

Greener and facile synthesis of 4,4′-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ol)s through a conventional heating procedure

A new catalytic application of tetraethylammonium L-prolinate for the facile and cleaner synthesis of 4,4′-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ol)s is developed. This amino acid-based ionic liquid could be recycled up to five runs, and a negligible reduction of catalytic activity was detected within the experimental error. A variety of substituted 4,4′-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ol)s were obtained in good to high yields under eco-friendly conditions. Tetraethylammonium L-prolinate is easy to prepare, as well as it shows moderate thermal stability and good solubility in water. This work revealed that this amino acid-based ionic liquid, containing L-prolinate anion, can catalyze the tandem Knoevenagel-Michael condensation reaction due to hydrogen bond donor and Lewis base moieties. The current methodology has other advantages, including (a) wide substrate-scope, (b) relatively short reaction times, (c) the use of a nontoxic, biocompatible, biodegradable and metal-free ionic liquid, and (d) simple workup procedure.

A Brief Synthesis of 2,2'-Arylmethylene Bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1- one) Catalyzed by TEAOH in Various Solvents.

2,2'-Arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) having four carbonyl functionalities along with their tautomeric keto-enol forms, is an important biologically active compound and important synthetic intermediate in the synthesis of xanthenes. This study was conducted in order to develop a new and concise method of synthesis of 2,2'-arylmethylene bis (3-hydroxy-5,5-dimethyl-2- cyclohexene-1-one) derivatives. TEAOH (20 mol %) was fond to be as a simple and efficient catalyst for the preparation of 2,2'-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives by the Knoevenagel condensation/Michael addition tandem reactions. A concise and practical method was developed for one-pot synthesis of 2,2'-arylmethylene bis(3- hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives catalyzed by TEAOH at room temperature in various solvents. This strategy provides several advantages over the traditional synthetic method, and is applicable to a wide variety of aromatic and heteroaromatic aldehydes at room temperature in various solvents.

Bronsted Acidic Ionic Liquids (BAILs)-Catalyzed Synthesis of 1,8-Dioxo-Octahydroxanthene and 2,2′-Arylmethylene Bis(3-Hydroxy-5,5-Dimethyl-2-Cyclohexene-1-One) Derivatives Under Eco-Friendly Conditions

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.

Guanidine hydrochloride catalyzed efficient one-pot pseudo five-component synthesis of 4,4′-(arylmethylene)bis(1H-pyrazol-5-ols) in water

The present methodology describes an efficient, environmentally friendly and simple protocol for the synthesis of some 4,4′-(arylmethylene)bis(1H-pyrazol-5-ol) derivatives through a one-pot pseudo-five-component reaction of hydrazine hydrate/phenyl hydrazine, ethyl acetoacetate, and various aromatic aldehydes catalyzed by guanidine hydrochloride. This condensation reaction was performed by tandem Knoevenagel–Michael reaction in water under refluxing conditions giving the title compounds in 82–92% yields. Atom economy, simple operation, easy work-up, using inexpensive organocatalyst, high yields in short times, clean transformation, and environmentally benign are some of the important features of this new protocol.

Synthesis, Characterization, and in vitro Antibacterial Evaluation of Barbituric Acid Derivatives

A series of 5,5′-(arylmethylene)bis[1,3-dimethyl-6-(methylamino)pyrimidine-2,4(1H,3H)-diones] have been synthesized by 2: 1 condensation of 1,3-dimethylbarbituric acid with armatic aldehydes in the presence of methylamine. The synthesized compounds have been characterized by 1H and 13C NMR, IR, and mass spectra and tested for their in vitro antibacterial activity against Bacillus subtilis, Staphylococcus aureus, and Pseudomonas aeruginosa. Some of the compounds have shown antibacterial activity exceeding that of ampicillin used as reference drug.

Design and Synthesis of Novel Cage like CuFe2O4 Hollow Nanostructure as an Efficient Catalyst for Synthesis of 4,4′-(aryl methylene)bis(3-methyl-1H-pyrazol-5-ol)s

Cage like CuFe2O4 hollow nanostructure has been synthesized successfully using hard template method under the hydrothermal condition. Cu(NO3)2·6H2O, Fe(NO3)2·9H2O and glucose were dissolved in water, and the mixture was heated to 180 °C in an autoclave. The removal of carbon was achieved by calcination at 800 °C and finally, the cage like CuFe2O4 hollow structure was obtained. This cage like CuFe2O4 hollow structure was characterized by FE-SEM, EDS, TEM and XRD. The catalytic performance of this hollow nanostructure was evaluated for the synthesis of bis pyrazol-5-ols. To this end, the one pot condensation reactions of phenylhydrazine, ethyl acetoacetate and different aromatic aldehyde at 80 °C under the solvent free condition were performed. The optimum amount of applied catalyst for this transformation was obtained to be 0.04 mol %. Noteworthy, catalyst was easily recoverable and was reused for 7 times with the remaining of its initial structure as well as its catalytic activity. Cage like CuFe2O4 hollow nanostructure are stably and efficiently attainable for conversion of precursors to 4,4′-(aryl methylene)bis(3-methyl-1H-pyrazol-5-ol)s

Melamine: An Efficient Promoter for Some of the Multi-component Reactions

Melamine, as an inexpensive and commercially available reagent, can be efficiently used for the promotion of the synthesis of 3,3′-(4-arylmethylene) bis-(4-hydroxycoumarins), 2,2′-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-ones) and 2-amino-4H-chromene derivatives. In addition to the mild conditions, this method provides other important advantages including simple work-up procedure, environmental friendliness, short reaction times, high yields of the products and use of a cheap, stable and reusable catalyst.

An efficient synthesis of 2,2'-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives using baker's yeast

An efficient synthesis of 2,2'-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) derivatives using baker's yeast

One-pot efficient pseudo-five-components synthesis of 4,4′-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ols) at room temperature assisted by K2CO3

ABSTRACTA convenient approach for the synthesis of 4,4′-(arylmethylene)-bis(3-methyl-1-phenyl-1H-pyrazol-5-ols) by an efficient one-pot reaction of aromatic aldehydes, phenylhydrazine, and ethyl acetoacetate by using substoichiometric amount of K2CO3 in acetonitrile solvent at room temperature is described. This protocol of one-pot synthesis produced a library of bis-pyrazolylmethane derivatives, a potential bioactive compound in very good to excellent yields.

In water–ultrasound-promoted synthesis of tetraketones and 2-substituted-1H-benzimidazoles catalyzed by BiOCl nanoparticles

A highly efficient, green protocol has been developed for the synthesis of various structurally diverse 2,2′-arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) and 2-substituted-1H-benzimidazole derivatives. The reaction was performed in water under ultrasound irradiation, using BiOCl nanoparticles as a catalyst. The nanocatalyst was found to be reusable for seven subsequent reactions without much loss in activity. Simple methodology with short reaction times and mild reaction conditions with easy work-up procedure are the salient features of this method.

Nano-CuFe2O4@SO3H Catalyzed Efficient One-Pot Cyclo-Dehydration of Dimedone and Synthesis of Chromeno[4,3-b]chromenes

ABSTRACTChlorosulfonic acid immobilized on CuFe2O4 nanoparticles (nano-CuFe2O4@SO3H) was evaluated as a recoverable catalyst for the one-pot cyclo-dehydration of dimedone and synthesis of chromeno[4,3-b]chromene derivatives by reaction of arylaldehydes, dimedone or 1,3-cyclohexanedione, with 3-hydroxycoumarine or 4-hydroxycoumarine in good to excellent yield. Also, 2,2′-Arylmethylene bis(3-hydroxy-5,5-dimethyl-2-cyclohexene-1-one) was synthesized by the reaction of aromatic aldehyde and dimedone using nano-CuFe2O4 in ethanol at room temperature. The catalyst could be recycled several times without significant loss of its catalytic activity. Clean methodologies, easy work-up procedure, high yield and simple preparation of the catalyst are some advantages of this procedure.

Efficient and Green Synthesis of 2,2′-(Arylmethylene)Bis-4-Pyrones in an Ionic Liquid [bmim+][BF4–

A series of sixteen 2,2′-(arylmethylene)bis(3-hydroxy-6-methyl-4H-pyran-4-ones) have been prepared in high yield via an ammonium acetate-catalysed three-component reaction of an aromatic aldehyde (1 equiv.) and allomaltol (2 equiv.) in an ionic liquid [bmim+][BF4–]. The reaction work-up is simple and the ionic liquid can be easily separated from the product and reused.

Sulfonated Honeycomb Coral (HC-SO3H): a new, green and highly efficient heterogeneous catalyst for the rapid one-pot pseudo-five component synthesis of 4,4′-(aryl methylene) bis(3-methyl-1H-pyrazol-5-ol)s

Sulfonated Honeycomb Coral (HC-SO3H), has been synthesized from the reaction of Honeycomb Coral with chlorosulfonic acid as sulfonating agent. The as-synthesized catalyst was characterized via XRF, FT-IR, TGA, SEM–EDS, XRD, BET and pH analysis. The superior catalytic activity of HC-SO3H was investigated for the synthesis of 4,4′-(aryl methylene)bis(3-methyl-1H-pyrazol-5-ol) derivatives through the one-pot pseudo-five component reactions. The main advantages of this protocol include simple procedure, excellent yields and short reaction times besides the non-toxicity, high stability and reusability of the catalyst.

Synthesis of 4,4´-(arylmethylene)bis(3-carboxymethyl-1-phenyl-1H-pyrazol-5-ol)s using an ionic liquid attached to colloidal silica nanoparticles in water_esi

Synthesis of 4,4´-(arylmethylene)bis(3-carboxymethyl-1-phenyl-1H-pyrazol-5-ol)s using an ionic liquid attached to colloidal silica nanoparticles in water_esi

ChemInform Abstract: Copper(0) Nanoparticles onto Silica: A Stable and Facile Catalyst for One‐Pot Synthesis of 2,2′‐Arylmethylene Bis(3‐hydroxy‐5,5‐dimethyl‐2‐cyclohexene‐1‐one) via Cascade Knoevenagel/Michael Reaction.

Solid supported copper (0) nanoparticles were prepared by physical adsorption of copper (0) nanoparticles (synthesized through bottom-up approach) on the solid supports such as silica, HAP, cellulose and basic alumina. Studies comparing these supported catalysts were done with the synthesis of arylmethylene-bis-(3-hydroxy-2-cyclohexene-1-one) via the cascade Knoevenagel/Michael reaction. The highly efficient catalyst was characterized by spectroscopic techniques like XPS, TGA, EDX, SEM, TEM and AAS. The biological importance of arylmethylene-bis-(3-hydroxy-2-cyclohexene-1-one) enforced us to synthesize these compounds catalytically using solid supported copper (0) nanopartcles.

Chemistry of 1,5-diketones: V. Hydrazination of acyclic and heterocyclic (poly)carbonyl compounds

Reactions of 2-(1-aryl-3-oxo-3-phenylpropylidene)-3,4-dihydronaphthalen-1(2H)-ones, 3-(1-aryl-3-oxo-3-phenylpropyl)-3,4-dihydro-2H-chromene-2,4-diones, and 3,3'-(arylmethylene)bis(3,4-dihydro-2H-chromene-2,4-diones) with hydrazine hydrate have been studied. Depending on the substrate structure, these reactions involve intramolecular heterocyclization with participation of the exocyclic double bond and sidechain carbonyl group or both oxo groups to give new pyrazole, indazole, and diazepine derivatives, as well as hydrazones.