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    Synthesis and Characterization of Cobalte Ferrite and Nickel Ferrite Nanocatalysts and Their Application in the C-X Bond Activation Reaction

    , M.Sc. Thesis Sharif University of Technology Aliabadi, Ali (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    Abstract
    Nowadays application of metallic catalysts in many of the organic reactions has been developed; therefore, different types of catalysts have been produced and used. In this way, in the first part of this thesis magnetic cobalt ferrite and nickel ferrite nanocatalysts were synthesized using co-precipitation method and their activity as catalyst was investigated in C-O bond formation reaction. This reaction was carried out between different types of aryl alcohols and aryl halides with good to excellent yields. The results showed that using N,N-dimethyl formamide as solvent, potassium carbonate as base and 5mol% of nanocatalysts at 80°C are the optimized condition for this reaction. In the... 

    Application of Spinel Ferrite and Samarium Catalysts in the Amination, Cyanation and other Organic Transformations

    , M.Sc. Thesis Sharif University of Technology Gholamtajari, Milad (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    Abstract
    In the first section, due to the important role of nanocatalysts in different fields of chemistry, magnetic metal ferrite nanoparticles were synthesized. Cobalt Cupper ferrite magnetic nanoparticles were synthesized using co-precipitation method and were characterized. The carbon−heteroatom bond forming reaction is one of the most important reactions in organic synthesis, pharmaceutical, dye, agrochemical, and biomolecules.1 Therefore, improvement of efficient methodologies for generating carbon−heteroatom bonds received considerable attention. An efficient protocol was developed for the nano CoCuFe2O4 catalyzed C-N and C-S bond formation. By this catalytic system, both amine and... 

    Preparation of Copper Salt of Para-amino Benzoic Acid Supported on Graphene Oxide as a Nanocatalyst and its Application in Some Organic Reactions

    , M.Sc. Thesis Sharif University of Technology Roknizadeh, Mostafa (Author) ; Mahmoodi Hashemi, Mohammad (Supervisor)
    Abstract
    The purpose of this study is to prepare a catalyst for copper nanoparticles that can be used in C-H activation processes in order to increase copper salt catalytic processes by converting it into a catalyst with characteristics of having recovery cycles, convenient separation and environmental friendliness and being in nano size. Consequently, copper nanoparticles are directly grafted onto graphene oxide, or using para-aminobenzoic acid grafted on graphene oxide. A copper nanoparticle catalyst was used in the reaction to activate the C(sp2)-H bonds of benzoxazole molecule and C-N bonds formation with secendary amines. Using the results of transition electron microscopy (TEM), scanning... 

    1, 3- Dipolar Cycloaddition Reactions of Azomethine Ylides of Ninhydrin with Chalcones and Investigation of Asymmetric Addition of TMSCN to Imines

    , M.Sc. Thesis Sharif University of Technology Assempour, Nazanin (Author) ; Saidi, Mohammad Reza (Supervisor) ; Jadidi, Khosrow (Supervisor) ; Mehrdad, Morteza (Co-Advisor)
    Abstract
    Part 1
    1,3-dipolar cycloaddition reactions offer convenient routes for the construction of a variety of five-membered heterocycles. This thesis represents a simple synthetic method via 1,3-dipolar cycloaddition reaction to prepare a novel class of spiro pyrrolidines and spiro pyrrolizidines which exhibit many biological activities. Non-stabilized azomethine ylides which generated in situ by the decarboxylative condensation of ninhydrin with proline and sarcosine were used as a 1,3-dipoles. On the other hand, chalcone and its derivatives with an impressive array of pharmacological activities were the dipolarophiles in these reactions. The reactions were carried out through reflax... 

    , M.Sc. Thesis Sharif University of Technology Ragheb Sarand, Akram (Author) ; Mahmoodi Hashemi, Mohammed (Supervisor) ; Rajab Zade, Ghadir (Supervisor)
    Abstract
    TiO2/SiO2/HPAsnanocompositeswas prepared by the sol-gel technique at room tempareture and used as the heterogeneous catalysts for the acylation of alcohols employing acetic anhydrid under solvent-free conditions at room tempareture. It was found that the catalytic activity of TiO2/SiO2/HPAs, in all cases of HPAs, was much higher than that of TiO2/SiO2. The most catalytic activity was obtained by TiO2/SiO2/H14NaP5W30O110 which completed the acylation reaction of benzyl alcohol at 1h. Examining the various concentrations of H14NaP5W30O110 in the composite, 9% w/w concentration of TiO2/SiO2/HPAs showed maximum catalytic activity, and by increasing the HPA concentration, activity remains... 

    Synthesis and Characterization of some Nitrogen Containing Heterocyclic Compounds Using Synthetic Intermediat of Isatin Analogues

    , M.Sc. Thesis Sharif University of Technology Zamani, Zanyar (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    Abstract
    An efficient catalyst-free one-pot three-component reaction was developed for the synthesis of a new family of N- and S-containing spirocyclic compounds.Various derivatives of spirobenzimidazolidine containing an indole scaffold were synthesized for the first time in a modestly toxic solvent and under mild reaction conditions. The reaction times were of the order of several minutes, and all the products were obtained in moderate to high yields (overall yields 58–80%)  

    Alkane Production from Biomass,Using Nano-Heterogeneous Catalysts

    , M.Sc. Thesis Sharif University of Technology Bastan, Farzad (Author) ; Kazemeini, Mohammad (Supervisor) ; Khorasheh, Farhad (Supervisor)
    Abstract
    Reduced supplies of fossil fuels worldwide attention to the economic and energy-efficient processes for the production of fuel from renewable sources is diverted.Biomass has the potential shown because it has features such as frequency and is renewable. Because of the high solubility of hydrocarbons derived from biomass in large amounts of water and oxygen, the process is then performed on the aqueous phase is considered. Recent research for the production of alkanes by the deformation of the aqueous phase (Aqueous Phase Reforming) by Catalyst on hydrocarbons derived from biomass, such as glycerol, ethylene glycol, sorbitol, glucose, and etc. has been done. Here is our attempt to use the APR... 

    Hydrogen Production by Aqueous Phase reforming of Glycerol Over Supported Platinum Catalysts

    , Ph.D. Dissertation Sharif University of Technology Larimi, Afsaneh Sadat (Author) ; Kazemeini, Mohammad (Supervisor) ; Mohammadi, Ali Asghar (Supervisor)
    Abstract
    The aqueous phase reforming (APR) of glycerol is an attractive yet challenging pathway to convert abundant biomass into value added hydrogen. Pt catalysts have received attention due to their ability to produce hydrogen-rich gas under APR conditions. In this work, the conversion of glycerol into hydrogen is demonstrated using Pt0.05CexZr0.95-xO2 (x=0, 0.29, 0.475, 0.66 and 0.95) solid solution catalysts and a series of M-doped Pt-MgO (M = Pd, Ir, Re, Ru, Rh and Cr) sheet-shaped nano-catalysts. Both characteristic (XRD, BET, H2-TPR, CO-chemisorption, TEM and XPS) and reactivity measurements were used to investigate the activity of the catalysts. Results indicated that reactivity depended on... 

    Synthesis of β-Amino Ketones Using Titania Based on Solid Acid as A Catalyst

    , M.Sc. Thesis Sharif University of Technology Samet, Masoud (Author) ; Mahmoudi Hashemi, Mohammad (Supervisor)
    Abstract
    Enanthioselective synthesis of biological molecules are so important in synthetic chemistry, and because of their biological activities, β-amino carbonyl compounds have earned so much attention in this area of chemistry. Mannich reaction is a classical method for synthesis of these molecules. The Mannich reaction is a three-component reaction between an enolizable CH-acidic carbonyl compound, an amine, and an aldehyde producing β-amino carbonyl compounds. But acidic or basic difficult circumstances, long reaction time, low yield and enantioselectivity, are the drawbacks of classical methods. In this project, we used titania-based solid acid as an enantioselective catalyst to overcome these... 

    (Synthesis of ZSM-5 Zeolite Doped with Cations such as Zn(II) & Fe(II

    , M.Sc. Thesis Sharif University of Technology Kazemi Zangeneh, Fatemeh (Author) ; Ghanbari, Bahram (Supervisor)
    Abstract
    In this study, we synthesized ZSM-5 and doped ZSM-5 applying cations such as Zn(II) and Fe(II). Furthermore, we synthesized [Zn,Fe]-ZSM-5 using similar method for the first time. The final products were characterised by X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. On the other hand, the hierarchical mesoporous Zn-ZSM-5 zeolite catalyst was prepared by alkali treatment by NaOH and Zn impregnation, and its application in the conversion of methanol to gasoline (MTG) process was studied. The modified zeolite samples after modification were also characterized by FT-IR and XRD methods. Zn impregnated mesoporous catalyst Zn-Alk-Z5 exhibited dramatic improvements in... 

    One-pot Synthesis of α-Aminonitriles by Reusable Co(II) Supported Nanocatalyst under Solvent-Free Conditions

    , M.Sc. Thesis Sharif University of Technology Ghiassian, Sara (Author) ; Saidi, Mohammad Reza (Supervisor) ; Rajabi, Fatemeh (Supervisor)
    Abstract
    Considering the widespread applications of α-aminonitriles, their synthesis is of great importance. The Strecker reaction represents a direct and appealing approach for the preparation of α-aminonitriles. With the aim of developing a mild and convenient approach towards the construction of α-aminonitriles, numerous methods have been reported for this important process over the past few decades. These have been mostly related to the optimization of reaction conditions and the use of more challenging substrates including ketimines and ketiminium salts and design of novel and effective catalytic systems. Due to the various advantages of supported heterogeneous catalysts and in our aim to... 

    Investigation of Bioleaching Extraction of Heavy Metals from Spent Catalyst in a Bioreactor

    , M.Sc. Thesis Sharif University of Technology Shahrabi Farahani, Mohammad (Author) ; Yaghmaei, Soheyla (Supervisor) ; Mousavi, Mohammad (Supervisor)
    Abstract
    Recovery of heavy metals from Hydrocracking spent catalyst was studied in a bioreactor by Acidithiobacillus thiooxidans. At first adaptation of microorganisms was done with spent catalyst in shaker flask. Using central composite design (CCD) the experiments were conducted in order to find optimized condition. Three factors such as particle size, pulp density and aeration rate were examined. Reduced cubic models were established to identify the relationship between the recovery percent of the metals and the variables. The results showed the maximum extraction of 87% Mo, 37% Ni and 15% Al were achieved after 7 days of batch process in bioreactor. The optimal values of variables were pulp... 

    Synthesis and Application of Transition Metal-Based Nanocatalysts (Pd, Pt, Ni, Co and Fe) in C-H and C-X Activation

    , Ph.D. Dissertation Sharif University of Technology Tavakoli Gheinani, Ghazal (Author) ; Matloubi Moghaddam, Firouz (Supervisor)
    Abstract
    In the first section, due to the important role of nanocatalysts in different fields of chemistry, magnetic metal ferrite nanoparticles were synthesized. Nickel ferrite and cobalt ferrite magnetic nanoparticles were synthesized using co-precipitation method and were characterized. Then, these nanoparticles which have been crystalized in spinel structure were employed to catalyzed different C-C and C-heteroatom bond formation reactions through C-X bond activaion. In all cases, the proposed catalytic systems could catalyze the reactions efficiently and the optimized reaction conditions were milder and more effective than the previous reported methods. In the next section, C-halogen bond... 

    Synthesis of new Modified Composites Based on Nanoporous Materials and their Application in Environmental Pollutant Degradation

    , M.Sc. Thesis Sharif University of Technology Zare Soheili, Hossein (Author) ; Gholami, Mohammad Reza (Supervisor)
    Abstract
    In this projekt, nanophotocatalysts containing metal oxides and oxy-acids based on the nanoporous materials were synthesized. The photocatalytic properties of the prepared samples were evaluated by the photodegradation of day moleculs in photocatalytic systems. The catalytic results revealed that Ag3VO4/Cu-MOF/rGO exhibits noticeably an improvement in both efficiency and rate of AB92 photodegradation in comparison with the pure Ag3VO4. Using different scanning mechanisms for the catalytic properties of the synthesized nanocomposites, it was clearly demonstrated that the anionic superoxide plays a decisive role. Reduction of 4-NP in the presence of NaBH4 was also used to investigate... 

    Solid-Liquid Heterogeneous Catalytic Reactions in a New Two-Impinging-Jets Reactor

    , M.Sc. Thesis Sharif University of Technology Ghasemi, Mohammad (Author) ; Molaei Dehkordi, Asghar (Supervisor)
    Abstract
    In this work the transesterification reaction of waste cooking oil in the present of solid catalyst as a type of solid-liquid catalytic reaction, has been studied. For this purpose, two types of alkali solid catalysts were synthesized. CaO-ZrO2 and KOH/γ-Al2O3 catalysts were prepared by co-precipitation and impregnation method, respectively. These catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray fluorescence (XRF), BET surface area, and temperature programmed desorption of CO2 (TPD-CO2). The obtained results for the CaO-ZrO2 catalysts indicate that with increasing Ca/Zr atomic ratio, the activity of catalysts increases, but the stability... 

    Direct Synthesis of Dimethyl Ether from Carbon Dioxide

    , M.Sc. Thesis Sharif University of Technology Taher Aslani, Mohammad Reza (Author) ; Kazemeini, Mohammad (Supervisor) ; Aghaziarati, Mahmoud (Co-Advisor) ; Kazemian, Masoud (Co-Advisor)
    Abstract
    In this research, direct synthesis of dimethyl ether (DME) from CO2 hydrogenation in three phase slurry reactor was investigated. Bifunctional catalysts composed of Cu- ZnO-Al2O3-ZrO2 as hydrogenation component and zeolite Na-Mordenite as dehydration component, with different Al2O3 and ZrO2 contents were synthesized by coprecipitating sedimentation and influences of Al2O3 and ZrO2 on CO2 conversion and DME selectivity were evaluated. Results show, both Al2O3 and ZrO2 enhanced conversion, but Al2O3 markedly increase selectivity of DME. However, when the total contents of Al2O3 and ZrO2 was increased up to 16 wt% , CO2 conversion and DME selectivity remarkably decreased. BET and XRD analyzes... 

    Synthesis and Characterization of a Copper Catalyst for Low Temperature Water –Gas Shift Reaction

    , M.Sc. Thesis Sharif University of Technology Rafiee Renani, Mansoureh (Author) ; Khorasheh, Farhad (Supervisor) ; Khandan, Nahid (Co-Advisor)
    Abstract
    Water Gas Shift (WGS) reaction is an old reaction in which syngas is used for producing Hydrogen. At the present time, the major application of this reaction is in fuel cells, since the necessary Hydrogen for these cells is provided by this reaction.
    The present study investigate the influence of different preparation methods on properties of Cu-ZnO/Al2O3 catalyst for water gas shift (WGS) reaction, which is now known as the Commercial catalyst for low temperature WGS, and its influence on performance of Cu-ZnO/Al2O3 catalyst to derive an optimal Cu-ZnO/Al2O3 catalyst for water gas shift (WGS) reaction. Cu-ZnO/Al2O3 catalysts was synthesized by CP, DP, DP-Ultra, IWI , CP-Urea, and... 

    Synthesis and Characterization of CoMo/γ-Al2O3 Catalyst for hydrodesulfurization process(HDS)

    , M.Sc. Thesis Sharif University of Technology Karimi, Mehrdad (Author) ; Kazemeini, Mohammad (Supervisor) ; Khorasheh, Farhad (Supervisor)
    Abstract
    The sulfur compounds in crude oil cause air pollution, metallic equipments’ corrosion and refinery catalysts poisoning like reforming catalysts. Therefore it is necessary to use hydrodesulfurization catalysts for sulfur content reduction. Hydrodesulfurization is the most common desulfurization method in the industry. In this method, sulfur compounds react with the hydrogen in presence of ComMo/γ Al2O3 catalyst and under hard operational conditions like high temperature ( 300-340 ͦC) and high pressure (20-100 atm of hydrogen). Then,these compounds are turned into hydrogen sulfide and hydrocarbons. In the next step, produced hydrogen sulfide will be eliminated from oil cutting.In this... 

    Synthesis and Characterization of Cu(II) Complexes with an Bidentate N,O-type Schiff Base Ligands and Study of the Catalytic Properties in Click Reactions

    , M.Sc. Thesis Sharif University of Technology Bayrami, Arshad (Author) ; Bagherzadeh, Mojtaba (Supervisor)
    Abstract
    Two new copper(II) complexes, [CuL2] and [Cu(phox)2], were synthesized by reaction of 1-((4-bromophenylimino)methyl)naphthalen-2-ol, HL, and 2-(2′-hydroxyphenyl)-2-oxazoline, Hphox, as ligands and copper(II) acetate mono-hydrate with the ratio 2:1 (ligand:metal), respectively. For characterization and structure determination of synthesized complexes, different techniques were performed such as FT-IR, elemental analyses (CHN), and X-ray crystallography. The geometry around Cu atom is almost square planar in both complexes. The catalytic activity of the complexes was evaluated in azide–alkyne cycloaddition reaction in water without need of any additional agent. The reaction conditions for the... 

    Kinetic Study of Heterogeneous and Homogeneous Catalytic Reactions in Molecular and Ionic Solvents and Their Mixtures

    , Ph.D. Dissertation Sharif University of Technology Khodadadi Moghaddam, Mohammad (Author) ; Gholami, Mohammad Reza (Supervisor) ; Habibi Yangjeh, Aziz (Supervisor)
    Abstract
    Solvatochromic parameters (ETN: normalized polarity parameter, π*: dipolarity/polarizability, β: hydrogen-bond acceptor basicity, α: hydrogen-bond donor acidity) have been determined for binary mixtures of propan-2-ol, propan-1-ol, ethanol, methanol and water with recently synthesized ionic liquid (2-hydroxyethylammonium formate) at 25 ◦C. The applicability of nearly ideal combined binary solvent/Redlich-Kister equation was proved for the correlation of various solvatochromic parameters with solvent composition. Solute-solvent and solvent-solvent interactions were applied to interpret the results. Heterogeneous catalytic hydrogenation of cyclohexene, catalyzed by Pt/Al2O3, was carried out in...