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In this research, synthesis of a novel magnetic 2-naphthalenesulfonic acid-grafted reduced graphene oxide quantum dot (Fe3O4-rGOQD-naphthalene-2-SO3H) via a five-step procedure has been described. The structure of this newly prepared Fe3O4-rGOQD-naphthalene-2-SO3H was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), energy-dispersive spectroscopy (EDX), thermogravimetric analytical (TGA), field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HRTEM) analysis. Synthesized Fe3O4-rGOQD-naphthalene-2-SO3H has been explored as a highly efficient and recoverable nanosensor and was prepared with different weight percentages of Fe3O4 (X = 99, 95, 90, 85% wt). The efficiency of Fe3O4-rGOQD-naphthalene-2-SO3H as a sensor was explored in nitrous oxide (NO2) gas probe at the concentration of 2.5–50 ppm NO2 at room temperature. Detection of NO2 by Fe3O4-rGOQD-naphthalene-2-SO3H was investigated under a series of different experimental conditions and the obtained results were compared with previously published methods. The results show that the detection range, the responsiveness, and the optimum temperature of Fe3O4-rGOQD-naphthalene-2-SO3H sensor were improved compared to other works.

A new and environmentally friendly non-caustic route to synthesize ultramicroporous carbon spheres (CS) via a simple one-step non-catalytic and activation-free chemical vapor deposition (CVD) method is described. The CVD method was applied at different temperatures, 600–900 °C; 800 °C was identified as the optimum for CS formation using a safe solid feedstock. The ultramicropores allow the effective interaction of the sorbent with CO2, resulting in high carbon capture capacity at both atmospheric and lower pressures. Specific surface area and total pore volume were influenced by the deposition temperature, leading to an appreciable change in overall carbon dioxide capture capacity. At atmospheric pressure, the highest CO2 adsorption capacities were ca. 4.0 mmol.g−1 and 2.9 mmol.g−1 at 0 °C and 25 °C, respectively, for the best CS. At lower pressure, 0.15 bar, the CO2 adsorption capacities were 2.0 mmol.g−1 and 1.1 mmol.g−1, again at 0 °C and 25 °C. The CS showed good sorption/desorption cyclability, ease of regeneration, favorable selectivity over N2 of 30:1 at 25 °C, and rapid kinetics. The proposed method is suitable for large-scale adoption since high pyrolysis temperatures are already used in multi-million-ton industries such as that of carbon black production.

In the present research, piperazine grafted-reduced graphene oxide RGO-N-(piperazine) was synthesized through a three-step reaction and employed as a highly efficient nanoadsorbent for H2S gas removal. Temperature optimization within the range of 30–90 °C was set which significantly improved the adsorption capacity of the nanoadsorbent. The operational conditions including the initial concentration of H2S (60,000 ppm) with CH4 (15 vol%), H2O (10 vol%), O2 (3 vol%) and the rest by helium gas and gas hour space velocity (GHSV) 4000–6000 h−1 were examined on adsorption capacity. The results of the removal of H2S after 180 min by RGO-N-(piperazine), reduced graphene oxide (RGO), and graphene oxide (GO) were reported as 99.71, 99.18, and 99.38, respectively. Also, the output concentration of H2S after 180 min by RGO-N-(piperazine), RGO, and GO was found to be 170, 488, and 369 ppm, respectively. Both chemisorption and physisorption are suggested as mechanism in which the chemisorption is based on an acid–base reaction between H2S and amine, epoxy, hydroxyl functional groups on the surface of RGO-N-(piperazine), GO, and RGO. The piperazine augmentation of removal percentage can be attributed to the presence of amine functional groups in the case of RGO-N-(piperazine) versus RGO and GO. Finally, analyses of the equilibrium models used to describe the experimental data showed that the three-parameter isotherm equations Toth and Sips provided slightly better fits compared to the three-parameter isotherms.

Micrometer long multilayer carbon nanoribbons with high oxygen content and nitrogen doping were obtained from the nitric acid treatment of Black Pearls 2000. The nanoribbons (NRs) exhibited yellow light emission under UV excitation. The oxidation of other grades of carbon black yielded irregular and small graphene oxide fragments or carbon quantum dots instead. Remarkably, the familiar and straightforward treatment of carbon materials with nitric acid reemerges as a powerful tool for the synthesis of technology-relevant carbon nanoribbons, and unlocking the potential of such straighforward oxidation chemistry applied to inexpensive and commercially available carbon black.

Microporous carbons were prepared starting from a series of benzene polycarboxylic acids following two strategies: (i) activation- and template-free pyrolysis and (ii) ion-exchange pyrolysis. The proposed synthetic strategies are facile approaches to produce highly microporous carbons that avoid the use of large amounts of corrosive and expensive chemical activators or templates. By varying the number of carboxylic acid groups, the charge balancing species and the degree of deprotonation of the precursors, microporous carbons with diverse morphologies, textural properties and oxygen contents were obtained and their CO2 and N2 sorption properties were assessed. The abundant micropores made the materials suitable for CO2 adsorption at low pressure and ambient temperature, achieving CO2 uptake as high as 4.4 mmol g−1 at 25 °C and 1 bar, competitive with those reported for porous carbons produced using large excess of alkali metal based activating agents. It was found that high performance, in terms of CO2 uptake and CO2/N2 selectivity, was linked to the simultaneous presence of large ultra-micropore volume and high oxygen content in the sorbents. This suggests that the interplay of ultra-microporosity and oxygen doping matters more than the two features taken singularly in determining the CO2/N2 separation properties of porous carbons at low pressure.

Weak forces can play an essential role in chemical reactions. Controlling such subtle forces in reorganization processes by applying thermal or chemical stimuli represents a novel synthetic strategy and one of the main targets in supramolecular chemistry. Actually, to separate the different supramolecular contributions to the stability of the 3D assemblies is still a major challenge. Therefore, a clear differentiation of these contributions would help in understanding the intrinsic nature as well as the chemical reactivity of supramolecular ensembles. In the present work, a controlled reorganization of an hexakis[60]fullerene-based molecular compound purely governed by the weakest van der Waals interactions known, i.e. the dihydrogen interaction – usually called sticky fingers – is illustrated. This pre-reorganization of the hexakis[60]fullerene under mild conditions allows a further selective hydrogenation of the crystalline material via hydrazine vapors exposure. This unique two-step transformation process is monitored by single-crystal to single-crystal diffraction (SCSC) which allows the direct observation of the molecular movements in the lattice and the subsequent solid–gas hydrogenation reaction., Weak forces play an essential role in chemistry. Controlling these supramolecular interactions will contribute to the creation dynamic absorbent materials with a variety of technological applications as chemosensors and environmental remediation.

In this study, a novel, simple, high yield, and scalable method is proposed to synthesize highly porous MoS

Carbon Black (CB) is one of the most abundantly produced carbon nanostructured materials, and approximately 70% of it is used as pigment and as reinforcing phase in rubber and plastics. Recent scientific findings report on other uses of CB that are of current interest, such as renewable energy harvesting and carbon capture. The present review focuses on the use and role of CB in renewable and environmental applications relevant to contemporary global challenges focusing specifically on clean energy. Key and recent research on the structure and chemistry of CB, including its uses as precursors to graphene quantum dots and hollow carbon spheres, is discussed in relation to renewable energy devices, electrochemical energy storage and environmental remediation. The surface chemistry of CB is closely related to that of graphitic and of turbostratic carbons through the predominant hexagonal carbon lattice from graphene fragments forming its basic structural units. Consequently, modern methods for grafting polymers and functional groups are easily translated to this abundant nanostructured material. Moreover, recent advances in electron microscopy that probe the structure of CB, and its electronic and physicochemical properties in nanocomposites revived the attention of what is wrongfully considered as a scientifically uninspiring material with limited potential for future technology breakthrough. CB has the potential to surge as a key player in renewable energy and environmental applications, meaning “When Black Turns Green”.

Engineering high recognition host-guest materials is a burgeoning area in basic and applied research. The challenge of exploring novel porous materials with advanced functionalities with the possibility of being largely scalable, prompted us to develop dynamic crystalline structures promoted by soft interactions. Herein, we demonstrate the first example of a pure molecular dynamic crystalline framework held together by means of weak van der Waals interactions. The presented organic fullerene-based material exhibits a non-porous dynamic crystalline structure capable of undergoing single-crystal to single-crystal reactions. Exposure to hydrazine vapors induce structural and chemical changes that evince the toposelective hydrogenation of alternating rings on the surface of the [60]fullerene. Control experiments confirm that the same reaction does not occur when performed in solution. This easily to detect change in the macroscopic properties paves the way for the real application of these materials.

In this work, a novel surface modification strategy was developed to modify polyethersulfone membrane substrate to create membranes for forward osmosis applications. A novel poly(ethylenimine) crosslinked Hexadecafluorodecanedioic acid polyelectrolyte was synthesized, followed by layer deposition on the surface of an ultrafiltration membrane substrate. While the unmodified membrane was negatively charged, this procedure reversed the surface charge, leading to a positively charged forward osmosis-nanofiltration membrane. Interestingly, at pH 7, the zeta potential approached 6.9 mV for membrane coated 4.5 as compared to the pristine membrane with a zeta potential value of approximately −11.0 mV. Extensive characterization and chemical analyses were carried out to ensure the effectiveness of the developed separation layer. The results revealed that the poly(ethylenimine) crosslinked Hexadecafluorodecanedioic acid was successfully deposited on the polyethersulfone membrane substrate. Preparation conditions, such as curing temperature and time were optimized. It was found out that membrane coated with 3.5 bilayers and cured at 60 °C for one hour exhibited optimal water permeability of 21.9 L m−2 h−1 bar‐1 of and solute permeability of 1.66 L m−2 h−1 as compared to the neat membrane.

Membranes having high water flux and minimum reverse solute flux at low operating pressures are the ideal membranes for the forward osmosis (FO) process. In this work, we report the use of a LbL surface modification strategy to fabricate a novel positively charged FO membranes. The main purpose of this work was to fabricate an effective selective layer onto a commercial PES ultrafiltration membrane, which functioned as a support layer, to provide the best performance for treatment of brackish water by FO. The new membranes containing a mixing ratio of 0.1 MPDADMAC: 0.001 MCMCNa in the polyelectrolyte complex exhibited the best performance in terms of minimum reverse solute flux and acceptable water flux as compared to that for membranes containing a mixing ratio of 0.1 MPDADMAC: 0.01 MCMCNa. The improved performance and physicochemical properties of the new membranes were explored by various analytical techniques and were compared to the pristine membrane. Firstly, structural characterization revealed that the new selective layer was homogenous, uniform and strongly adhered to the substrate resulting in excellent water permeability and acceptable reverse solute flux. Secondly, it was found that the optimal curing temperature was 60 OC for 4 h that contributed to enhanced membrane performance. Lastly, the developed ranking protocol was adopted to optimize the membrane performance in terms of the water permeability coefficient (A) and solute permeability coefficient (B). According to this optimization procedure, the best performing membrane was membrane coated 2.5 bilayers which had water permeability and solute permeability coefficients of 23.1 L m−2 h−1 bar−1 and 1.54 L m−2 h−1 respectively.

In this study, a novel, simple, high yield, and scalable method is proposed to synthesize highly porous MoS2/graphene oxide (M−GO) nanocomposites by reacting the GO and co-exfoliation of bulky MoS2 in the presence of polyvinyl pyrrolidone (PVP) under different condition of ultrasonication. Also, the effect of ultrasonic output power on the particle size distribution of metal cluster on the surface of nanocatalysts is studied. It is found that the use of the ultrasonication method can reduce the particle size and increase the specific surface area of M−GO nanocomposite catalysts which leads to HDS activity is increased. These nanocomposite catalysts are characterized by XRD, Raman spectroscopy, SEM, STEM, HR-TEM, AFM, XPS, ICP, BET surface, TPR and TPD techniques. The effects of physicochemical properties of the M−GO nanocomposites on the hydrodesulfurization (HDS) reactions of vacuum gas oil (VGO) has been also studied. Catalytic activities of MoS2-GO nanocomposite are investigated by different operating conditions. M9-GO nanocatalyst with high surface area (324 m2/g) and large pore size (110.3 A), have the best catalytic performance (99.95%) compared with Co-Mo/γAl2O3 (97.91%). Density functional theory (DFT) calculations were also used to elucidate the HDS mechanism over the M−GO catalyst. It is found that the GO substrate can stabilize MoS2 layers through weak van der Waals interactions between carbon atoms of the GO and S atoms of MoS2. At both Mo- and S-edges, the direct desulfurization (DDS) is found as the main reaction pathway for the hydrodesulfurization of DBT molecules.

In the present study, multiwall carbon nanotubes (MWCNTs) were modified to produce novel carbon-based material called allylamide-grafted multiwall carbon nanotubes (AGMWCNTs). The Fourier transform infrared spectroscopy characterization of AGMWCNTs demonstrated major peaks indicating functional groups such as O H/NH, C H and C O stretching. Adsorption of H 2 S by AGMWCNTs was studied under different experimental conditions and the results were compared with those obtained by oxidized MWCNTs (OMWCNTs). Analysis of the effects of contact time and temperature on the H 2 S adsorption indicated that AGMWCNTs exhibit a higher adsorption capacity than OMWCNTs, which may be attributable to their effective nitrogen functionalities. Moreover, comparison of breakthrough curves describing the time-dependence of H 2 S output concentrations indicated that the H 2 S output concentration of AGMWCNTs after 55 min was about 2-fold lower than that of OMWCNTs. Finally, analyses of the equilibrium models used to describe the experimental data showed that the three-parameter isotherm equations Toth and Sips provided slightly better fits compared to the three-parameter isotherms.

Functionalized graphene has been prepared and employed for the solvent-free synthesis of some novel and known benzoyl-1,4-diazanaphthalene from the condensation of various arylglyoxals with 4-bezoyl-1,2-phenylenediamine. Catalyst loads as low as 0.003 g could be used leading to high yields of pure products. Magnetic, geometry, and electronically based indices have been also employed to investigate the correlation between aromaticity variation in new formed ring (ring A) and yield of reaction.

A simple hydrothermal process has been developed for the synthesis and assembly of copper and silver nanoparticles to aggregates. The reduction of Cu2+ and Ag+ ions to the zerovalent metal was performed by glyoxal in the absence of any external agent. The produced glyoxylic acid (GA) in the redox process stabi- lized metallic copper and silver particles and rendered them oxidation resistant for several months and dispersible in polar organic solvents and water. Detailed nanostructures of synthesized products were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The results demonstrated that assembly of nanoparticles to aggregates and their regularity were dependent on the reaction conditions such as temperature and concentration of the starting material. The Ostwald ripening process was proposed to explain the formation of copper nanoparticles by TEM observation at several times during the reaction. The existence of the surface stabilizing agent was identified by Fourier Transform infrared spectroscopy (FT-IR) and thermogravimetric analyses (TGA).

Nano gamma alumina (NGA) was prepared via a simple synthetic route and used for the preparation of a nanofluid in various salinities on the water-wet sandstone core samples. A new waterflooding experiment on sandstone rock for enhanced oil recovery (EOR) has been used by taking into account different water salinities. In this paper, the impressiveness of a new EOR process in the presence of alumina-based nanofluids to alter the dynamic adsorption of the sandstone core sample in low- and high-salinity brine injection has been experimentally studied. The nanofluids with a suitable concentration of NGA particles and salinities ranging from 2000 to 200 000 ppm and 25–80 °C were prepared. The results showed a reduced adsorption by the use of nanoparticles at low-salinity conditions. The ultimately optimum recoveries for 2000, 20 000, and 200 000 ppm of nanofluid injection were obtained as 56.95, 64.78, and 71.48%, respectively. It was found that these oil recoveries strongly depend upon the concentration of sa...

Multiwall carbon nanotubes were functionalized and then used as powerful nanocatalyst for the one-pot, three-component synthesis of new spiroindolones. Functionalized multiwall carbon nanotubes (FMWCNTs) showed a good catalytic ability and recyclability in the current reaction. The present strategy offers some interesting advantages such as simplicity, high yields of products, and non-toxic nature.

This is the first use of copper aluminate nanoparticles (CuAl2O4 NPs) as efficient catalyst for the multicomponent organic synthesis. The CuAl2O4 NPs was prepared and characterized by XRD, SEM, and TEM for this purpose and applied in the green synthesis of pyranonaphthoquinones (α-lapachone derivatives) under solvent-free conditions. The nanocatalyst can be recycled and reused for four times.

In the present study, nanocrystallite copper ferrite (CuFe2O4) has been obtained via two different methods. In the first method, CuFe2O4 with an average particle size of 7.6 ± 0.5 nm was synthesized by pyrolysis of iron and cupferron as a chelating agent. In the second method, CuFe2O4 nanoparticles with an average particle size of 22.3 nm were synthesized by combined microemulsion and homogenous precipitation methods. The effective parameters for the synthesis procedures were determined and optimized using L8 and L4 Taguchi designs. Different techniques to characterize the structure and morphological properties of nanoparticles are X-ray diffraction, thermogravimetric analysis, scanning electron microscopy, Brunauer–Emmett–Teller, transmission electron microscopy, Dynamic light scattering, and elemental micro analysis. Crystal violet (C25N3H30Cl) as a model pollutant and UV lamp as an energy source were applied for the investigation of the photocatalytic activity of nanocrystalline CuFe2O4 powders. The 97 % degradation of crystal violet could be obtained around 100 min.

Magnetic nano-sized copper ferrite was prepared via a simple synthetic route and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). We found that copper ferrite nanoparticles (CuFe2O4 NPs) possessed high catalytic activity in the one-pot reaction of isatin with malononitrile and Michael donors for the synthesis of spirooxindoles. The magnetic nano-sized copper ferrite exhibited several advantages such as stability, safety, and easy recyclability. The novel procedure for the synthesis of spirooxindoles has some interesting features such as high efficiency, simplicity, high rate and environmental safety, good to excellent product yield, and avoidance of toxic organic solvents.

Benzenesulfonic acid-grafted graphene (BS-rGO) was synthesized through a three-step reaction, characterized, and employed as a highly efficient nanoadsorbent for hydrogen sulfide removal. The materials including precursors and final adsorbent were fully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, and atomic force microscopy (AFM). The operational conditions of 4000–6000 h −1 space velocities and 60,000 ppm H 2 S feed concentrations were examined on adsorption capacity. Furthermore, temperature optimization within the range of 30–70 °C was set which significantly improved the adsorption capacity of the nanoadsorbent. After 3 h, the amount of H 2 S output concentration by GO, rGO, and BS-rGO was found as 369 ppm, 488 ppm, and 220 ppm, respectively. Hydrogen sulfide adsorption analysis showed a good result to eliminate the H 2 S using nanoadsorbent.

A novel extended triazole-based ligand (PM-Tria) has been synthesized and an unprecedented MOF 3D has serendipitously been formed by assembling iron(II), PM-Tria ligand and fluoride anions. This MOF contains a perfectly linear one-dimensional {Fe(II)–F}n bridging chain that shows an antiferromagnetic behaviour. Furthermore, the structure is compared with a 14th century mosaic found in the Alhambra Palace in Granada showing a surprising symmetry resemblance.

In this research, hydrogen sulfide is adsorbed on amido-functionalized reduced graphene oxide (AFRGO) as a nanoadsorbent. By the use of n-propylamine and allylamine, reduced graphene oxide (RGO) was amidated for the adsorption of hydrogen sulfide. The materials were characterized by adsorption of H2S, potentiometric titration, scanning electron microscopy (SEM), Fourier-transform infrared (FT-IR) spectroscopy, and X-ray diffraction (XRD) analysis. The effect of the operational conditions of 4000–6000 h−1 space velocities and 60,000 ppm H2S feed concentrations were examined on adsorption capacity. The results show that H2S feed concentration, space velocity, and functional groups of adsorbents have a major effect on H2S adsorption. It was also found that the temperature in the range of 30–70°C had a significant effect on H2S adsorption. The concentration of H2S adsorbed in 3 h by AFRGO containing allyl substituent, AFRGO containing propyl substituent, graphene oxide (GO), and reduced graphene oxide (RGO) w...

Multiwalled carbon nanotubes were oxidized and then utilized as new heterogeneous nanocatalyst for the efficient one-pot, four-component synthesis of pyrazolopyranopyrimidinones. This present strategy offers important advantages in terms of its simplicity, low catalyst loadings, catalyst recyclability, high product yields, and non-toxic nature.

A carbon nanotube-supported metallo carboxyporphyrin has been synthesized and characterized by X-ray diffraction (XRD), field-emission scanning electronic microscopy (SEM), and Fourier transform infrared spectroscopy (FT-IR). The prepared catalyst has been evaluated for the removal of mercaptan from gas stream in a fixed bed reactor. The effect of important operating parameters including temperature, gas hourly space velocity (GHSV), and loading (%) was investigated on the mercaptan removal. The results confirmed that the mercaptan concentration could be reduced from 16,800 ppm to less than 10 ppm under optimized conditions by (Fe)TCPP-MWCNTs-NH 2 as nanocatalyst.

One-pot synthesis of some pyranocoumarins and biscoumarins using graphene oxide nanosheets as efficient catalyst has been investigated. The green methods offer appealing attributes such as excellent yields, short reactions times, use of a safe and recyclable catalyst, and a simple workup procedure.

In this work, new, efficient, and environmentally adapted synthesis of benzylpyrazolocoumarins in one-pot is introduced. From tri-component reaction of a wide range of aryl aldehydes, 4-hydroxycoumarin, and 3-methyl-1-phenyl-2-pyrazolin-5-one on water, benzylpyrazolocoumarins with good to excellent yields in a green procedure were synthesized. The highly efficient role of ferrous ammonium sulfate hexahydrate (Mohr’s salt) as a new green catalyst in this synthesis is obviously demonstrated. This novel procedure is an effective, cheap and environmentally adapted route to the synthesis of benzylpyrazolocoumarin derivatives. The crude products recrystallized to afford the crystalline pure product. This novel procedure has some advantages such as high efficiency, simplicity, high rate and environmental safety.

A one-pot condensation between a wide range of aryl aldehydes and 5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one by employing ZnO nanoparticles as recyclable and highly efficient catalyst to produce new and known bis(pyrazolyl)methanes in aqueous media is introduced. This efficient and new method to bis(pyrazolyl)methanes has some advantages, such as the use of a safe and reusable catalyst, simple operation, short reaction times, and good to excellent yields of the products.

A new series of triheterocyclic compounds containing pyrazole, pyran, and pyrimidinone rings was synthesized via a one-pot condensation of ethylacetoacetate, hydrazine hydrate, barbituric acid, and aromatic aldehydes in the presence of catalytic amounts of titanium dioxide nanowires. Various functional groups were well tolerated under the optimized reaction conditions.

A one-pot synthesis of novel aroylamido coumarins from the reaction of 4-hydroxycoumarin with aryl glyoxals and benzamides in the presence of a catalytic amount of tungstate sulfuric acid (TSA) is described. The method is operationally simple and provides access to a variety of aroylamido coumarins in good yields.

A one-pot, three-component synthesis of warfarin-like compounds from the reaction of benzamide, aryl glyoxal and 4-hydroxycoumarin is described. Zirconium oxychloride octahydrate catalyzed the reactions efficiently under solvent-free conditions to yield desired products in good yields.

A convenient and rapid procedure for the synthesis of calix[4]resorcinarenes as useful supramolecules has been developed via a reaction of aryl aldehydes with resorcinol in the presence of yttrium(III) nitrate under solvent-free conditions. This eco-friendly method has many appealing attributes such as excellent yields, short reactions times, and simple work-up procedures.

An efficient method for the synthesis of new aryloylamido coumarins via a one-pot, three-component reaction of an aryl glyoxal, benzamide, and a 4-hydroxycoumarin in the presence of molybdate sulfuric acid under solvent-free conditions is reported. This high yielding reaction is in accordance with green chemistry aspects.

An expeditious method to prepare pyranocoumarins containing an aroyl group by the three-component reaction of 4-hydroxycoumarin with arylglyoxals and malononitrile is described. The reaction is efficiently catalyzed by Mohr’s salt, and the products were obtained in good to excellent yields with high purity. The method is simple, inexpensive, and environmentally friendly.

In this study, a novel and highly efficient catalyst was produced from a reaction between silica chloride and sodium hydrogen carbonate. This novel catalyst was named silica sodium carbonate (SSC), and was characterized by FT-IR, XRD, XRF and TG-DT analyses, atomic absorption and titration with HCl (0.01 N). Furthermore, herein, the first application of SSC as a green, highly efficient and recyclable catalyst to the synthesis of new 1,4-dihydropyrano[2,3-c]pyrazoles is successfully examined. Compared to the classical reactions for the synthesis of 1,4-dihydropyrano[2,3-c]pyrazoles, the presented procedure using SSC has some advantages than others such as excellent yields of products, short reaction times, green and safety procedure, easy handling and reusability of catalyst.

A series of synthetic methods for synthesis of organic compounds containing naphthyloyl group have been explored via one-pot reactions catalyzed by zinc oxide nanowires (ZnO NWs). In the first reaction, new biscoumarins have been synthesized through the reaction of naphthyl glyoxals with 4-hydroxycoumarin. In the next one, new pyranocoumarins have been obtained from the one-pot, three component reaction of naphthyl glyoxals with malononitrile and 4-hydroxycoumarin. In the final study, the naphthyl glyoxals were also employed for the synthesis of new amidocoumarins in a three-component reaction with 4-hydroxycoumarin and benzamide. It is noteworthy to mention that the green chemistry principles have been considered in all strategies. The advantages of the present methods are good product yield in a short reaction time, avoidance of toxic and expensive organic solvents, use of safe and recoverable catalyst, and simple operation.