Sharif Digital Repository

Considerable effort has been directed in recent years towards the transition metal complex catalyzed oxidation of organic compounds. Herein the synthsis of the iron complex of bis(oxazoline) ligand as a novel catalyst is reported, and the catalytic activity of this complex in oxidation of sulfides is investigated. Bis(2-oxazolynil)methane as ligand is prepared by condensation of diethylmalonate with 2-aminoethanole in 1:2 molar ratio and finally corresponding complex is synthesized by the reaction between FeCl3.6H2O and Bis(2-Oxazolynil)methane in 1:1 molar ratio. The complex is characterized by using IR, UV-Vis, cyclic voltametery, conductometery and elemental analysis data. Moreover,... 

The aim of this study is to mimic water oxidizing complex to find new materials and also to understand their rules in this matter. To achieve this, manganese complexes containing 2,4,6-tris (2-pyridyl)-1,3,5-Triazine, 1,10-phenanthroline, 1,10-bipyridine, Schiff base, amino acids, 2,6-pyridinedicarboxylic acid, 2-pyridinecarboxylic acid have been synthesized and characterized by elemental analysis, IR, EPR, ESI-MS, electronic absorption spectroscopy, electrochemistry, X-ray diffraction and oxygen evolution in presence of oxone and Ce(IV). It is shown that the reaction between Mn(II) complexes containing 2,4,6-tris¬(2-pyridyl)-1,3,5-Triazine, 1,10-phenanthroline, 1,10-bipyridine,... 

The goal of this project was study on coordination behavior of the 14-membered macrocyclic ligand of type N2O2 aza-crown while it is attached to fullerene C60 nano-particle. For this purpose, firstly the macrocyclic ligand (Fig 3-1, L1) was synthesized and then was reacted with C60 (Fig 3-1, L2) of which the product was characterized by elemental analysis. Since the product was insoluble in any solvents, further study on its coordination chemistry was impossible. In a second procedure, the macrocyclic ligand was reacted with benzylbromide. The reaction mixture gave two macrocyclic ligands with different number of benzylic pendant groups (Fig 3-1, L3-L4). The products were separated by column... 

In our previous work in this laboratory, macrocycle containingO_2 N_2 and O_2 N_3- donor set with various ring size were synthesized. The intraction of macrocyles with [60]fullerene were determined. In this research, we synthesized 22-membered aza-crown macrocycle ligand containing O_4 N_2- donor set and characterized by NMRspectroscopy. The intraction of macrocycle with [60]fullerene were also investigated by UV-Visible spectroscopy. The formation constant was determined applying Benesi--Hildebrand equation. The result has been showed that O_4 N_2 macrocyle had better complexation with [60]fullerene in comparision of O_2 N_3 and O_2 N_2 donor sets. Then, the interaction of O_4 N_2 with... 

New dioxomolybdenum(VI) complex has been synthesized by reacting N-hydroxyphenyl-[5-(triphenylphosphonium)methyl]salicylideneamine chloride (PPh3-H2sap) as a water soluble ligand and [MoO2(acac)2] in ethanolic solution. The water soluble ligand (PPh3-H2sap) was prepared by reaction of 2-aminophenol with (3-formyl-4-hydroxybenzyl)triphenylphosphonium chloride as a water solublesalicylaldehyde derivative. The resulting complex with the formula [MoO2(PPh3-H2sap)(EtOH)] which contains an ethanol molecule in sixth site of coordination, was characterized by elemental analyses, 1H NMR,31P NMR, IR and UV-Vis spectroscopic studies. This complex was tested as a catalyst for the homogeneous... 

Viability and proliferation of cells in cell culture mainly depends on i) cell culture medium, ii) cell-cell interaction, and iii) the supporting scaffold. Among these factors, and within recent years, surface and mechanical properties of the supporting ECM has attracted many researchers. Experiment results show that the animal cell adhesion is accelerated on stiffer scaffolds. Electrical charge of the scaffold is also a determinant term in the kinetics of adhesion and on a relatively charged scaffold, one can expect an increment in kinetics of adhesion front movement. This is due to the natural negative charges of the cell wall membrane. In this thesis, an analytical model is proposed to... 

By considering previous works undertaken in our laboratory on the interaction between O2N2 azacrown and [60]fullerene using UV-vis spectroscopy. It was found that the significant interaction occurs in less than one hour. Extending this time in this research, the reaction between [60]fullerene with 15 to 19 membered N2O2-azacrown macrocyclic ligands was investigated during ten days. The new compounds L1, L2 were synthesized and characterized applying HPLC, ESI-Mass, TG, DSC, IR as well as elemental analysis. The interaction of new compounds with Cu(II) and Ni(II) and Co(II) using UV-vis spectroscopy showed that L2 gave the highest Kb value of cations/(L1, L2). Besides, it was found that the... 

In this research, four N2O2–azacrown macrocyclic ligands with naphthalene pendant arms (L1-L4) were synthesized using direct synthesis. The products were characterized applying 1H and 13C {1H} NMR spectroscopy, IR and Mass spectrometry. Interaction of these ligands with [60]fullerene and Cu(II) were monitored respectively by fluorescent as well as UV-vis spectroscopy and applying Benesi-Hildebrand equation. These intercations were compared with N2O2 macrocyclic ligands in previous experiments in terms of their calculated association constants (Ka). According to our results, the presence of naphthalene pendant arm groups led to increase the interaction with [60]fullerene compared to the... 

In the present research, two series of N2O2- and N4O2-naphthadiaza-crown macrocyclic ligands with different macroring size, 15-21 memberd (L1-L7) were synthesized using direct method. The products were characterized by applying 1H and 13C NMR, IR spectroscopy, mass spectrometry and elemental analysis and in some cases by X-ray crystallography. Firstly, to study on emission properties of naphthadiaza-crown macrocyclic ligands as a fluorophore, we employed different amines as fluorescence quencher. It was observed that the quenching effects of 3o aliphatic amines like triethylamine were more pronounce than other group of amines. Also, the quenching constants for interactions of macrocyclic... 

Ethylene is considered as one of the key materials in the petrochemical industry and has a particular importance. Polymerized ethylene produces polyethylene, which is widely used in plastics and pipe-manufacturing industries. Ethylene is mainly produced by the processes of catalytic cracking or thermal cracking of heavier hydrocarbon compounds. In these processes, acetylene is produced as a by-product, which deactivates the Ziegler-Nata catalysts in the polymerization unit of ethylene. Therefore, there should be some considerations to reduce acetylene to its minimum value -around zero. For this purpose, the fixed bed catalytic reactor is used to hydrogenate acetylene to ethylene. Various... 

In this project, M2 macrocyclic ligand, bearing three pyridine side arms (3p) was synthesized and characterized by employing elemental analysis and 1H NMR, 13C NMR and IR methods. The interaction of 3p with zinc tetraphenylporphyrin was investigated, using fluorescence and UV-vis spectroscopy in solution phase. The observed quenching in the fluorescence spectrum alongside Q band shift in UV-vis spectrum indicate on the interaction of 3p with ZnTPP. The formation constant for these interactions in 1:1 ratio was calculated 10100 M-1, employing fluorescence method. The formation constant was calculated 630 M-1 for 1:2 ratio for 3p:ZnTPP. Having 1:2 ratio 3pZnTPP was also synthesized and... 

In recent years, much attention has been focused on quantum dot films due to their high amount of surface area and their size-dependant band-gap tenability. However, high surface area results in increase in energy traps in case of insufficient surface passivation. In this research, PbS colloidal quantum dots were synthesized via hot injection route having the size of 3 nm approximately. Then cationic doping with Zn, Ca and Cd and ligand exchange of long oleic acid with short organic mercaptopionic acid were done. Excitonic peak of these dots and photoluminescence peak appeard in wavelengths of 930 and 1100 nm respectively. Optimum film thickness was also determined as 300 nm. Quantum dot... 

In this study, a number of complex cobaloxim complexes [Co(DMG)2LX] in which L= 4-MePy, 3-MePy, 4-bzPy, 3-CNPy, 4-CNPy, tBuPy, styPy, NaphPy synthesized and their structure studied. These complexes were identified by FT-IR and 1H NMR methods as well as their solid state structure studied by X-ray crystallography of single crystals. Gaussian 09 software was used to optimize the geometric structure and obtain the vibrational frequency of cobalt complexes. Charge decomposition Analysis (CDA) and molecular orbital studies were performed using the AOMix 6.88 software. Also, the characterization of σ-donating and П-acceptoring of pyridine ligands in these complexes was investigated using... 

The aim of this study at the outset is synthesis of ligands with the ability to bridge formation between two groups i.e. C60 and Cobalt Schiff base complex (CoSALEN). Hence, four Schiff base ligands with pyridine electron donor moiety in one side, and such electron donor moiety pyridine, phenol and aniline in another side were synthesized and characterized by elemental analysis, 13C¬NMR, 1HNMR and IR Spectroscopy. In next step the interaction of these Schiff base ligands with CoSALEN complex and Fullerene C60, in the mixture of two solvents, i.e. toluene/dimethylsulfoxide and benzene/methanol was explored separately by UV-Visible Spectroscopy and their kinetic studies were also undertaken... 

Mesoporous silica nanoparticles have broad application in drud delivery systems due to their porous structure, functionalization, biocompatibility, high surface area and pore volume. Neverthless, pure mesoporous silica nanoparticles without functionality were not smart material and could not release drug in triggered and controlled manner. For this reason, using smart polymeric coating would be considered. Polymer shells also provide colloidal stability, improved blood circulation lifetime and reduced toxicity which are crucial for efficient in vivo drug delivery. Inflammatory and tumor tissue have low pH and high temperature as compared to health tissue. Therefore, using pH and... 

A new dioxomolybdenum(VI) complex, (Cis-[MoO2(L)])n, has been synthesized by reacting 4-bromo-2-((2-hydroxy-5-methylphenylimino)methyl)phenol as a ligand and [MoO2(acac)2] in methanolic solution. For characterization and structure determination of the synthesized complex, different techniques were performed such as elemental analyses, 1H NMR, IR, UV-Vis and X-ray crystallography. The complex was tested as a catalyst for the homogeneous epoxidation of olefins, using tert-butyl hydperoxide (TBHP) as an oxidant. The catalytic system showed high yield, selectivity and turnover number in olefin epoxidation reactions under atmospheric conditions. For example, when the molar ratio of catalyst,... 

Rhenium(I) tricarbonyl complexes with NN-donor ligands display promising properties for potential applications as molecular catalysts for the reduction of carbon dioxide and as biocompatible pro-drugs for the controlled release of carbon monoxide. In this context the diimine type ligands are one of the most widely used bidentate chelating moieties. In this work, several [Re(CO)3(DAB)X] complexes were prepared in a standard manner by replacement of two cis CO groups in the starting bromo- or chloro-pentacarbonylrhenium complexes with 1,4-diazabutadiene (DAB) ligands. Their pseudo-octahedral facial structures were established using FT-IR, 13C-NMR and 1H-NMR and confirmed by X-ray... 

Two new dioxomolybdenum(VI) complexes have been synthesized by the reaction of N,N'-bis(5-chlorosalicylidene)-2,2'-dimethyl-1,3-propanediamine and N,N'-bis(5-bromosalicylidene)-2,2'-dimethyl-1,3-propanediamine as Schiff base ligands with [Mo(O)2(acac)2] in methanolic solution.and their electronic structures have been investigaged theoretically. The Schiff base ligands H2L1 and H2L2 were prepared by reaction of 5-Chlorosalicylaldehyde and 5-Bromosalicylaldehyde with 2,2'-dimethyl-1,3-propanediamine, respectively. The result of these reactions, was two complexes of Mo(O)2L1 and Mo(O)2L2 .The compounds were characterized by elemental analyses (CHN), and 1HNMR and IR spectroscopic techniques.... 

The first part of this thesis describes the synthesis and characterization of several Mn, Fe and Mo complexes containing tridentate Schiff base and oxazoline ligands and their reactivities as catalysts in the oxidation of organic compounds like olefins and sulfides, as well. The crystal structures of newly prepared cis-dioxo-bis[2-(2′-hydroxyphenyl)-oxazolinato]molybdenum(VI), cis-[MoO2(phox)2] and (N-hydroxyphenyl-salicylidenamine)(acetylacetonato)ethanol iron(III), [FeIII(N-OPh-sal)(acac)EtOH] complexes have been described by X-ray crystallography. Due to the difficulties in the preparation of suitable single crystals of novel...