An efficient catalysis for the synthesis of pyrimido[1,2-a]benzimidazoles and 1-(benzothiazolylamino)methyl-2-naphthols using ZnO@SO3H@Tropine.

In this research and in the line of our researches on the use of nano-substrates modified with ionic liquid in organic reactions, an efficient and green method for the one-pot three-component synthesis of pyrimido[1,2-a]benzimidazole and 1-(benzothiazolylamino)methyl-2-naphthol derivatives is reported using a new nanoporous catalyst formulated as ZnO@SO3H@Tropine. Further analysis of the catalyst for its characterization has been performed using thermal gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), energy dispersive spectrometer (EDS) and Fourier-transform infrared spectroscopy (FT-IR). The present approach creates a variety of biologically active heterocyclic compounds with excellent yields and short reaction times. Among the other advantages of the current method are: ease of operation, clean reaction profiles and ease of separation. Also, this catalyst can be reused five times without loss of its catalytic activity.

Comparison of the effectiveness of two piperazine based nano-catalysts in the synthesis of benzoxazoles and benzimidazoles and use of the powerful one in the N-Boc protection of amines.

In this work, a comparison between the catalytic activity of two piperazine based ionic liquids immobilized on ZnO NPs and SiO2 NPs is presented in the synthesis of benzoxazoles and benzimidazoles. These reactions are performed under solvent free conditions during appropriate reaction times with high yields. The catalyst obtained from ZnO-NPs (PINZS), as the more efficient one, is used for the efficient promotion of the N-Boc protection of amines. High chemoselectivity, no by-products, facile separation of the catalyst, short reaction times and no need for volatile organic solvents are the best features of the proposed methods.

Copper salt of a DABCO-based molten salt: a high-performance catalyst in the one-pot synthesis of 3,4-dihydropyrimidine and polyhydroquinoline derivatives.

In this study, [DABCO](SO3H)2CuCl4 as a novel DABCO-based molten salt with dual acidic functionality (Brønsted and Lewis) has been synthesized, characterized and used as a high-performance catalyst in the one-pot synthesis of 3,4-dihydropyrimidine and polyhydroquinoline derivatives. The identification of this catalyst was accomplished by using techniques such as infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermo gravimetric analysis (TGA), field emission scanning electron microscopy (FESEM) and energy dispersive X-ray (EDS) spectroscopy. Excellent efficiency, short reaction times, a simple working method and also use of a recyclable catalyst are the considerable advantages of this process.

Facile synthesis of triazolo/benzazolo[2,1-b]quinazolinone derivatives catalyzed by a new deep eutectic mixture based on glucose, pregabalin and urea.

In this study, a novel natural deep eutectic solvent was prepared from glucose, pregabalin, and urea. The prepared solvent was identified using a variety of techniques, including Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), derivative thermogravimetry (DTG), differential thermal analysis (DTA), and refractive index measurements (RI). The prepared deep eutectic solvent was then utilized for the one-pot synthesis of quinazolinone derivatives. The yields of the product obtained with and without the catalyst were determined, providing insights into the catalytic efficiency of the system. This protocol offers several advantages, including mild reaction conditions, easy reagent preparation, a green process, short reaction times (2-60 min), high yields (80-99%), and a straightforward procedure with the possibility of catalyst reusability.

Ag/g-C3N4 nanocomposite: Green fabrication and its application as a catalyst in the synthesis of new series of depsipeptides as biologically active compounds and investigation on their anti-breast cancer activity.

In this study, we bring forward a green and novel eco-friendly strategy for the fabrication of Ag/g-C3N4 nanocomposite via a fast in-situ generation method using Ferula Gummosa extracts as both stabilizer and reducing agent. Ag/g-C3N4 nanocomposite was analyzed by Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX-MAP), and transmission electron microscopy (TEM). After procurement and characterization, the catalytic activity of the prepared reagent was surveyed in the synthesis of a new series of depsipeptides using aspirin/ketoprofen, cyclohexyl isocyanide, and aryl aldehydes at ambient temperature in EtOH/H2O as a green media. Taking into account the economic and environmental facets, the method bestows some advantages such as using plant extracts as green media for the preparation of Ag nanoparticles, simple work-up procedure, mild reaction conditions, short reaction times, and high yields of the products. Additionally, the Ag/g-C3N4 nanocomposite catalyst can be recycled effectually and reused several times without a substantial loss in reactivity.

Additively manufactured MAX- and MXene-composite scaffolds for bone regeneration- recent advances and future perspectives.

Human bones can suffer from various injuries, such as fractures, bone cancer, among others, which has initiated research activities towards bone replacement using advanced bio-materials. However, it is still challenging to design bio-scaffolds with bone-inducing agents to regenerate bone defects. In this regard, MAX-phases and MXenes (early transition metal carbides and/or nitrides) have gained notable attention due to their unique hydrophilicity, bio-compatibility, chemical stability, and photothermal properties. They can be used in bone tissue engineering as a suitable replacement or reinforcement for common bio-materials (polymers, bio-glasses, metals, or hydroxyapatite). To fabricate bio-scaffolds, additive manufacturing is prospective due to the possibility of controlling porosity and creating complex shapes with high resolution. Until now, no comprehensive article summarizing the existing state-of-the-art related to bone scaffolds reinforced by MAX-phases and MXenes fabricated by additive manufacturing has been published. Therefore, our article addresses the reasons for using bone scaffolds and the importance of choosing the most suitable material. We critically discuss the recent developments in bone tissue engineering and regenerative medicine using MAX-phases and MXenes with a particular emphasis on manufacturing, mechanical properties, and bio-compatibility. Finally, we discuss the existing challenges and bottlenecks of bio-scaffolds reinforced by MAX-phases and MXenes before deriving their future potential.

Hyaluronic acid coated spinel ferrite for combination of chemo and photodynamic therapy: Green synthesis, characterization, and in vitro and in vivo biocompatibility study.

In this project, different photosensitizers were prepared using different ratios of nickel, manganese, and iron. Then, multiple analysis were performed to evaluate their efficiency, and the most suitable one was used to be coated by hyaluronic acid to improve the nano-platform's biocompatibility and target ability. Moreover, another chemical targeting agent (riboflavin) was used to further improve the target ability of the prepared nano-platform. Different spectroscopies and thermal analysis were used to determine the physical and chemical characteristics of the prepared nano-platform. Also, in order to determine the biocompatibility of the nano-platform, in vitro and in vivo tests such as blood hemolysis, blood aggregation and lethal dose were performed. Then, an anti-cancer agent (curcumin) was loaded on the selected nano-platform to makes us able utilizing the synergistic effect of chemotherapy and photodynamic therapy simultaneously. Finally, the cell cytotoxicity results showed that the prepared nano-platform had a great anti-cancer potential which can make it a great candidate as a dual photo and chemo therapy agent for treatment of breast cancers.

Synthesis, characterization, and application of α-Fe2 O3 @TiO2 @SO3 H photo-Fenton catalyst for photocatalytic degradation of biologically pre-treated wood industry wastewater.

The efficiency of removing chemical oxygen demand (COD) and turbidity from wood wastewater was investigated using a sequencing batch reactor (SBR) and the photo-Fenton process. A total of 94.78% of COD reduction and 99.9% of turbidity removal were observed under optimum conditions of SBR, which consisted of an organic loading rate (OLR) of 0.453 kg COD m-3  day-1 , mixed liquor suspended solids (MLSS) of 4564 mg L-1 , and cycle time of 48 h. A magnetic α-Fe2 O3 @TiO2 @SO3 H nanocatalyst was prepared as a heterogeneous Fenton reagent. The Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), and elemental mapping (MAP) analyses were performed to determine the structure and morphology of synthesized photocatalyst. The response surface methodology (RSM) was used to optimize the process based on a central composite design (CCD). The maximum photocatalytic degradation of 87.54% and COD reduction of 83.35% were achieved at a dosage of 0.6 g L-1 of catalyst, 30 mg L-1 of H2 O2 , and pH of 3.5 for 45 min. The results indicated that a combination of the SBR process and α-Fe2 O3 @TiO2 @SO3 H could be used as an effective method for the treatment of wood wastewater. PRACTITIONER POINTS: A combination of the SBR and photo-Fenton process was introduced as an impressive method for wood industry wastewater treatment. The efficiencies of COD, BOD5 , NO3 -N, PO4 -P, and color removal were obtained according to the standard limits in Iran. To our knowledge, this study is the first report of the use of synthesized α-Fe2 O3 @TiO2 @SO3 H photocatalyst for the wood industry wastewater treatment.

Synergic Antitumor Effect of Photodynamic Therapy and Chemotherapy Mediated by Nano Drug Delivery Systems.

This review provides a summary of recent progress in the development of different nano-platforms for the efficient synergistic effect between photodynamic therapy and chemotherapy. In particular, this review focuses on various methods in which photosensitizers and chemotherapeutic agents are co-delivered to the targeted tumor site. In many cases, the photosensitizers act as drug carriers, but this review, also covers different types of appropriate nanocarriers that aid in the delivery of photosensitizers to the tumor site. These nanocarriers include transition metal, silica and graphene-based materials, liposomes, dendrimers, polymers, metal-organic frameworks, nano emulsions, and biologically derived nanocarriers. Many studies have demonstrated various benefits from using these nanocarriers including enhanced water solubility, stability, longer circulation times, and higher accumulation of therapeutic agents/photosensitizers at tumor sites. This review also describes novel approaches from different research groups that utilize various targeting strategies to increase treatment efficacy through simultaneous photodynamic therapy and chemotherapy.

Manganese Dioxide (α-MnO2) and Graphene Oxide (GO) Nanocomposites: An Efficient Promotor for the Oxidative Deprotection of Trimethylsilyl, Tetrahydropyranyl and Methoxymethyl Ethers.

Manganese dioxide (α-MnO2) and graphene oxide (GO nanocomposites were prepared and successfully characterized using Fourier-transform infrared (FT-IR), field emission scanning-electron microscopy (FE-SEM), and energy-dispersive X-ray spectroscopy (EDX) mapping methods and Xray diffraction (XRD) analyses. This reagent is an efficient catalyst for the aerobic oxidation of trimethylsilyl (TMS), tetrahedropyranyl (THP), and methoxymethyl ethers (MOM) to their corresponding carbonyl compounds in the presence of K2CO3. All reactions were performed in n-hexane under mild and completely heterogeneous reaction conditions. Our novel method has the advantages of excellent yields, short reaction times, availability and reusability of the catalyst and simple and easy work-up procedure compared to the conventional methods reported in the literature.

Salen-decorated Periodic Mesoporous Organosilica: From Metal-assisted Epoxidation to Metal-free CO2 Insertion.

We clicked a salen ligand onto a thiol-ethane bridged periodic mesoporous organosilica (Salen-PMO) using a photo-initiated thiol-ene click reaction. This process resulted in a covalently bonded salen ligand on the PMO material. The final BET surface area amounts 511 m2 /g and the pore size diameter is approximately 7 nm. The functionalized PMO material showed an excellent carbon dioxide uptake capacity of 1.29 mmol/g at 273 K and 1 bar. More importantly, by coordinating a MoO2 2+ complex onto the Salen-PMO material, we obtained a heterogeneous catalyst with a good catalytic performance for the epoxidation of cyclohexene. The catalyst was highly reusable, as no decrease in its activity was observed for at least four runs (99% conversion). Finally, the metal-free Salen-PMO showed an exceptional catalytic performance in the cycloaddition of CO2 to epoxides. The obtained results clearly demonstrate the versatility of the Salen-PMO material not only as metal-free catalyst but also as a support material to anchor metal complexes for specific catalytic applications. With the same catalytic platform, we were able to firstly create epoxides out of alkenes, and subsequently turn these epoxides into cyclic carbonates, consuming CO2 .

Preparation and application of α-Fe2O3@TiO2@SO3H for photocatalytic degradation and COD reduction of woodchips industry wastewater.

In this study, we investigated the efficiency of photocatalytic degradation and chemical oxygen demand (COD) reduction from woodchips industry wastewater using α-Fe2O3@TiO2@SO3H. A magnetic α-Fe2O3@TiO2@SO3H was prepared as a heterogeneous photo-Fenton catalyst. The Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), and elemental mapping (MAP) analyses were performed to determine the structure and morphology of synthesized photocatalysts. The response surface methodology (RSM) was used to optimize the photo-Fenton process based on a Box-Behnken design (BBD). The parameters such as catalyst dosage, H2O2 dosage, pH, and contact time on photocatalytic degradation and the reduction of COD were studied. The maximum photocatalytic degradation of 93.75% and COD reduction of 86.54% were achieved at a dosage of the catalyst of 1 g L-1, H2O2 dosage of 40 mg L-1, and a pH of 3.5 at 45 min. The kinetics of the photo-Fenton process was studied for the woodchips wastewater treatment under optimum conditions. The pseudo-second-order kinetic model for photocatalytic degradation and COD reduction was obtained. The results indicated that a α-Fe2O3@TiO2@SO3H could be used as an effective heterogeneous photocatalyst for the treatment of woodchips industry wastewater. Preparation and application of α-Fe2O3@TiO2@SO3H for photocatalytic degradation and COD reduction of woodchips industry wastewater.

Fe3O4@MCM@ZrCI2: A Practical Magnetic Mesoporous Zirconium-Based Nanocomposite as a Reusable Catalyst for the Synthesis of Spirooxindoles.

In the present study, we aimed to investigate the catalytic role of the newly reported MCM-41 -based nanocomposite in which the low acidity of this mesoporous moiety was favourably improved via the stabilization of zirconium nanoparticles and was magnetized to make a facile work-up procedure as an applicable and efficient method. The prepared Fe3O4@MCM-41 @ZrCI2 nanocomposite was successfully characterized using different analyses and then it was favourably exploited for the synthesis of spirooxindoles as the most prominent spiro compounds. As predicted, Fe3O4@MCM- 41 @ZrCI2 showed considerable efficiency in the promotion of the studied reaction.

Treatment of wood industry wastewater by combined coagulation-flocculation-decantation and fenton process.

In the present research, the efficiency of turbidity and chemical oxygen demand (COD) reduction from the wood industry wastewater (WIW) by the use of a combined coagulation-flocculation-decantation (CFD) - Fenton process was studied. Firstly, the performance of three coagulants such as ferric chloride (FeCl3 ), aluminum sulphate (alum), and polyaluminum chloride (PACl) was evaluated. The polyacrylamide (PAM) was used as a flocculant. The results showed that the polyaluminum chloride had a high removal efficiency. The COD reduction of 84.1% and turbidity removal of 82.0% of were obtained in coagulation-flocculation-decantation (CFD). Secondly, Fenton process was optimized, by the use of a response surface methodology (RSM), with application of a central composite design (CCD). The maximum turbidity and COD removal obtained by this process were 94.1% and 72.5% respectively, under optimal conditions ([Fe2+ ] = 250 mg/L, [H2 O2 ] = 500 mg/L, pH 3.5, time 60 min). The kinetics of COD and turbidity removal were determined by the model of first order. In conclusion, the combination of coagulation-flocculation-decantation (CFD) - Fenton process presented as a remarkable method for wood wastewater treatment. PRACTITIONER POINTS: A combination of coagulation-flocculation-decantation and Fenton process was introduced for the wood industry wastewater treatment. A designed experimental approach for treatment of wood industry wastewater using a Fenton process was studied. The yields of COD, BOD5 , N-NO3 , P-PO4 , and dye removal were obtained according to the standard limits in Iran.

Agar-entrapped sulfonated DABCO: Agelly acidic catalyst for the acceleration of one-pot synthesis of 1,2,4-triazoloquinazolinone and some pyrimidine derivatives.

In this project, a recently synthesized DABCO-based catalyst is entrapped in agar to reduce its moisture sensitivity leading to enhancement of its stability and catalytic activity. After preparation and identification this new reagent is used as an efficient and environmentally safe catalyst for the preparation of 1, 2, 4-triazoloquinazolinone and some pyrimidine derivatives. This method is accompanied with some superiorities such as, simple operation, mild and green conditions, use of low cost and non-hazardous natural material, short reaction times, easy preparation methods and simple work-up procedures. The prepared catalyst can be re-used for several times in all of the studied reactions without any appreciable loss in its activity.

Introduction of Succinimide as A Green and Sustainable Organo-Catalyst for the Synthesis of Arylidene Malononitrile and Tetrahydrobenzo[b] pyran Derivatives.

AIM AND OBJECTIVE: In this work, we tried to introduce a non-toxic and stable organic compound named succinimide as a green and efficient organo-catalyst for the promotion of the synthesis of arylidene malononitrile and tetrahydrobenzo[b]pyran derivatives. Using this method led to a clean procedure to achieve these types of bioactive compounds without a specific purification step. The rate and yield of the reactions were excellent, and also succinimide showed acceptable reusability as the catalyst. MATERIALS AND METHODS: In a 25 mL round-bottom flask, [A: a mixture of aromatic aldehyde (1 mmol), malononitrile (1.1 mmol) and B: a mixture of aromatic aldehyde (1.0 mmol), malononitrile (1.1 mmol)] and succinimide (0.2 mmol) in H2O/ EtOH [5 mL (1:1)] was stirred at 80 °C for an appropriate time. After completion of the reaction, which was monitored by TLC [n-hexane-EtOAc (7:3)], the mixture was cooled to room temperature, and the solid product was filtered, washed several times with cold distilled water to obtain the corresponding pure product. RESULTS: After the optimization of the conditions and amount of the catalyst, a series of aromatic aldehydes containing either-electron-donating or electron-withdrawing substituents were successfully used for both of the reactions. The reactions rates and yields under the selected conditions were excellent. The nature and electronic properties of the substituents had no obvious effect on the rate and yield of the reaction. Meanwhile, the catalyst showed acceptable reusability for these two reactions. CONCLUSION: In this work, we have introduced Succinimide as a green and safe organo-catalyst for the efficient synthesis arylidene malononitrile and tetrahydrobenzo[b]pyran derivatives. The results showed that the catalyst had excellent efficiency in green aqueous media and also the reusability of the catalyst was good.

Fe3O4/g-C3N4 Nanocomposites as a Reusable Catalyst for the Synthesis of 5-Arylidenepyrimidine-2,4,6-(1H,3H,5H)-Trione and Pyrano-Pyrimidinone Derivatives in Aqueous Media.

A green magnetic nanocatalyst is developed by immobilization of Fe3O4 on Graphitic carbon nitride (g-C3N4) support for the efficacious synthesis of 5-arylidenepyrimidine-2,4,6-(1H,3H,5H)-trione and pyrano-pyrimidinone derivatives in aqueous media. The most momentous features of the present protocol are the simple preparation of the catalyst, mild reaction conditions, short reaction times and high yields of the products. Moreover, the magnetic nanocatalyst Fe3O4/g-C3N4 can be recycled effectively and reused several times, without a significant loss in reactivity.

Fe3O4@SiO2-Sultone: A Novel and Recyclable Magnetic Nanocatalyst for the Efficient Synthesis of 3,4 Dihydropyrano[c]Chromenes and 2-Amino-4H-Chromene Derivatives.

A green, simple and eco-friendly procedure for the preparation of 3,4-dihydropyrano[c]chromenes and 2-amino-4H-chromene derivatives is described using Fe3O4@SiO2-Sultone as a novel and efficient magnetic nanocatalyst. All reactions are performed under mild conditions and all products are obtained in high yields during short reaction times. The catalyst can be easily isolated from the reaction mixture by magnetic decantation using an external magnet and reused at least five times without significant degradation in the activity.

Magnetic Fe3O4/Graphene Oxide/Copper-Based Nanocomposite as a Reusable Catalyst for the Reduction of 4-Nitrophenol.

In the present investigation, Fe3O4/Graphene oxide/Pr-NH2-CuII was reported as a novel magnetically recoverable nanocomposite and characterized using various analytical techniques such as FT-IR spectroscopy, field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), vibrating sample magnetometry (VSM), X-ray diffraction (XRD), and inductively coupled plasma (ICP). The catalytic performance of the synthesized catalyst was evaluated in the reduction of 4-nitrophenol to 4-aminophenol by an excess amount of sodium borohydride as the source of hydrogen in aqueous solution. The reaction was monitored by UV-vis spectroscopy at ambient temperature. Magnetic nature of the catalyst led to its simple recovery by a permanent magnet and excellent recyclability without appreciable loss of the catalytic activity.

Nanostructured γ-Fe2O3@Starch-n-Butyl SO3H as New Recyclable Magnetic Catalyst for Promoting Multi-Component Reactions.

Butane-1-soltunic acid modified starch-coated γ-Fe2O3 magnetic nanoparticles [γ-Fe2O3@starch-n-butyl SO3H] was easily prepared through a ring opening reaction of 1, 4-butane sultone with nano-magnetic γ-Fe2O3@starch. After structural studies, using FT-IR, SEM, XRD, TGA, TEM, EDX, VSM and also pH analysis the efficiency of this reagent in the preparation of tetrahydrobenzimidazo[2,1-b] quinazolin-1(2H)-ones and 2H-indazolo[2,1-b]phthalazine-triones was studied. Operational simpleness, high yields, short reaction times, wide applicability and simple recyclability of the catalyst employing an external magnet are the most important advantages of this methodology.