The current study examined the effect of metal oxide catalysts on the sorption and photocatalytic efficiencies for the removal of ciprofloxacin and ofloxacin in water. ZnO and TiO2 catalysts are prepared using a suitable method based on the sol-gel process، which have a great change in structural and textural properties. The structure and surface area of the synthesized catalysts were characterized، and used as sorbents/catalysts to remove antibiotics from water. Results showed a high adsorption capacity for the Titania oxide related to its great surface area، it is about 280 m2 g-1، compared to that of ZnO catalyst with only 19 m2 g-1. However، both photocatalysts exhibit a difference in photocatalytic activity versus both drugs. Therefore، ZnO، as a competitor catalyst for the TiO2، provides the most effective treatment of contaminated water with antibiotic pollutants to produce suitable reused water.

In this research، a green، operationally simple، highly efficient and facile cascade Biginelli reaction using various aromatic aldehydes، ethyl acetoacetate، and urea/thiourea has been developed. First، the ionic liquid was prepared from the reaction of 1- methyl-2-pyrolidone with methane sulfonic acid. Then، this ionic liquid was applied as an acidic catalyst in the synthesis of dihydropyrimidinones as a target product under mild conditions. The ionic liquid and resulting products were characterized by physical and spectral data such as melting point، IR، 1HNMR and 13CNMR. The significant advantages of this protocol are short reaction time، excellent yields and easily available starting materials.

The preparation of trans-dihydrofurans has been achieved by a one-pot condensation reaction of 4-bromophenacyl bromide، aromatic aldehydes and 5،5-dimethyl-1،3-cyclohexanedione using biosynthesized CuO nanoparticles under reflux conditions in ethanol. CuO nanoparticles (CuO NPs) were prepared using extract of leaves of Ajuga chamaecistus Subsp. Scoparia. The key advantages of this process are the diastereoselective synthesis، reusability of the catalyst، low catalyst loading، excellent yields، short reaction times، simple workup and environmentally benign. Fully optimized structures of trans and cis dihydrofurans were obtained by B3LYP/6-31G(d،p) method. The structures of the prepared trans-2،3-dihydrofurans were fully characterized by 1H and 13C NMR spectra، IR spectra، and elemental analysis.

In this research، magnetic animal bone meal nanoparticles functionalized with ethylenediaminetetraacetic acid (Fe3O4@ABMEDTA) is reported as a green recyclable catalyst that catalyzed synthesis of biscoumarin derivatives in water. The catalyst was characterized by the Fourier transform infrared spectroscopy (FT-IR)، thermogravimetric analysis (TGA)، differential thermogravimetric (DTG)، scanning electron microscope (SEM) and X-ray diffraction (XRD). This study has demonstrated that Fe3O4@ABM-EDTA can act as an efficient catalyst for synthesis of biscoumarines in the presence of water as solvent at reflux conditions. A wide range of aldehydes could react with 2-hydroxycoumarin and give biscoumarin derivatives in excellent yields. Moreover، Fe3O4@ABM-EDTA was magnetically recovered and reused for five cycles without any significant loss of efficiency.

In this paper، a new nano-size ionic liquid (nIL) has been synthesized from D-phenylalanine and oxalic acid (D-Phe-OX) via a
simple procedure. The obtained nIL has been characterized by the fourier transform infrared spectroscopy (FT-IR)، energydispersive
X-ray spectroscopy (EDAX)، thermogravimetric analysis (TGA)، nuclear magnetic resonance spectroscopy (1H
NMR)، and field emission scanning electron microscopy (FESEM)، techniques. The synthesized nanocatalyst has been used for
the three-component one-step synthesis of functionalized spirolactones via the condensation reaction of arylamines، DMAD and
isatins. The stereoselective preparation of dispirodihydrofuranyl oxindoles has also been examined successfully through the onestep
pseudo-four component condensation of isatins، amines and DMAD، respectively.

A hydrophobic-bentonite catalyst (cetyltrimethyl ammonium bromide-bentonite) has been used as a very mild، neutral، ecofriendly، reusable، non-toxic، low-cost and easily available catalyst. It was prepared by replacing the exchangeable Na+ cations of a homoionic Na–bentonite with cetyltrimethyl ammonium bromide (CTMAB) cations. The catalyst was characterized by XRD، BET and SEM. The BET data and XRD patterns showed that the surfactant ions enter the interlayer space of catalyst. In order to study the catalytic properties، we carried out a one-pot practical، efficient and green multicomponent synthesis of 4Hbenzo-[b]-pyran derivatives in terms of high yield، simple experimental procedure، low reaction time and simple work-up.

SBA-15 is an interesting mesoporous silica material having highly ordered nanopores and a large surface area، which is widely employed as a catalyst. This mesoporous silica due to silanol groups is easily functionalized by various organic materials. A new acidic ordered functionalized mesoporous silica (SBA-15-Aminopropyl-Benzyl-SO3H) has been introduced as an efficient catalyst for solvent-free esterification of fatty acids with ethanol. The structure of the catalyst and prepared materials have been characterized by FT-IR spectroscopy، XRD، thermogravimetric analysis (TGA)، TEM، acid-base titration and NH3-TPD techniques and N2 adsorption– desorption isotherm. The high loading acidic sites with hydrophobic nature of the catalyst facilitate the esterification reaction in high yield without using special methodology. The results demonstrated that the reaction can also be performed in water as an environmentally benign and inexpensive solvent. The catalyst has been easily separated from the reaction mixture and used for at least six reaction runs without any significant loss of activity.

Metal-organic framework 5 (MOF-5) and bimetallic MOF-5s (Co/Zn and Ni/Zn) were prepared via a simple solvothermal method. Samples were characterized by various techniques such as powder X-ray diffraction (XRD)، Fourier transform infrared (FT-IR)، scanning electron microscopy (SEM)، UV-Vis diffuse reflectance spectroscopy (DRS)، inductively coupled plasma (ICP) and elemental analysis (EA). Photocatalytic decolorization of methylene blue (MB) dye in the aqueous solutions was examined under UV and visible light irradiation. The degradation of MB solutions was calculated by changes in the UV–Vis absorbencies of the aqueous solutions at λmax = 664 nm. The influence of various parameters such as the catalyst loading، dye concentration، initial pH of the dye solution and adding electron acceptors (H2O2، tert-Butyl hydroperoxide (TBHP)، KBrO3، KIO4 and (NH4)2S2O8) on the degradation reaction was studied. Moreover، metal doping can improve the photocatalytic activity of MOF-5 due to the synergistic effect، narrow band gap and so on. The results show that Co/Zn-MOF-5 photocatalyst exhibited better photocatalytic activity than Ni/Zn-MOF-5 and raw MOF-5 for MB decolorization under UV and visible light irradiation. Furthermore، adding different electron acceptors، except TBHP، enhanced the photocatalytic performance of photocatalysts with a different rate. Also، kinetic studies revealed that the reactions follow pseudo-first-order. Additionally، bimetallic MOF-5s did not show obvious activity reduction in MB decolorization during five recycling usages.

A three-component process for the one-pot synthesis of 6-amino-4-aryl-5-cyano-3-methyl-1-phenyl-1،4-dihydropyrano[2،3-c]pyrazoles is described by the three-component reaction of aldehydes، 3-methyl-1-phenyl-1H-pyrazol-5(4H)-one and malononitrile in the presence of Fe3O4@FSM-16-SO3H as an efficient magnetically recyclable mesoporous catalyst. Folded sheet mesoporous material (FSM-16) was prepared by intercalation of a layered، kanemite type sodium silicate with cetyltrimethylammonium (CTMA) ions in the presence of dispersed Fe3O4. The Fe3O4@FSM-16-SO3H was synthesized by sulfonation of Fe3O4@FSM-16 and characterized by FESEM، XRD، BET، VSM and FT-IR techniques. This protocol suggests benefits in terms of higher yields and short reaction time. In addition، the catalyst could be separated using an external magnet and is reusable many times without any significant loss of activity.

Maryam Sadat Ghasemzadeh was born in Ghaen/ Southern Khorasan، Iran. She received her B.Sc. in Pure Chemistry from Imam Khomeini International University and M.Sc. in Organic Chemistry from Birjand University under the supervision of Professor Sara Sobhani. She is currently studying her Ph.D. in Ferdowsi University of Mashhad under the supervision of Professor Batool Akhlaghinia. Her current research focuses on new heterogeneous nanocatalysts to develop new methods of organic synthesis.