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Catalytic activity of manganese(III)-oxazoline complexes in urea hydrogen peroxide epoxidation of olefins: The effect of axial ligands
, Article Journal of Molecular Catalysis A: Chemical ; Volume 260, Issue 1-2 , 2006 , Pages 163-169 ; 13811169 (ISSN) ; Latifi, R ; Tahsini, L ; Sharif University of Technology
2006
Abstract
The catalytic activity of two manganese(III)-oxazoline complexes [Mn(phox)2(CH3OH)2]ClO4 and Mn(phox)3 (Hphox = 2-(2′-hydroxylphenyl)oxazoline), was studied in the epoxidation of various olefins. All of epoxidation reactions were carried out in (1:1) mixture of methanol:dichloromethane at room temperature using urea hydrogen peroxide (UHP) as oxidant and imidazole as co-catalyst. The epoxide yields clearly demonstrate the influence of steric and electronic properties of olefins, the catalysts and nitrogenous bases as axial ligand. [Mn(phox)2(CH3OH)2]ClO4 catalyst with low steric properties has higher catalytic activity than Mn(phox)3. The highest epoxide yield (95%) was achieved for indene...
Stability of binary and ternary copper (II) complexes of 2((4-methyl-5-nitro-6-(pyrrolidine-l-yl)pyrimidine-2-yl) amino) propionic acid in aqueous solution
, Article Scientia Iranica ; Vol. 21, Issue. 6 , 2014 , pp. 2029-2035 ; ISSN: 10263098 ; Bagherzadeh, G ; Khaleghian, M ; Kermani, M ; Sharif University of Technology
Abstract
The acidity and stability constants of M (MNPPAP) (MNPPAP: 2((4-methyl-5-nitro-6-(pyrrolidine-l-yl)pyrimidine-2-yl)amino)propionic acid) M: Cu2+, Cu (Bpy)2+ (Bpy: 2,2'-Bipyridine), or Cu(Phen) (Phen: 1,10-Phenanthroline) complexes were determined by potentiometric pH titration. It is shown that the stability of the binary Cu (MNPPAP) complex is determined by the basicity of the carboxylate group on one side and amine group on the other side. It is demonstrated that the equilibrium, Cu(Har)2+ (H ar: Heteroaromatic ligand such as Bpy or Phen) + Cu(MNPPAP) ^ Cu(Har)(MNPPAP) + Cu2+, is displacement due to the well known experience that mixed ligand complexes formed by a divalent 3d ion, a...
Modeling of an ultrasound system in targeted drug delivery to abdominal aortic aneurysm: a patient-specificin silico study based on ligand-receptor binding
, Article IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control ; Volume 69, Issue 3 , 2022 , Pages 967-974 ; 08853010 (ISSN) ; Boroumand, A ; Ebrahimi, S ; Kalantarnia, F ; Maleki, S ; Moradi, H ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2022
Abstract
Targeted drug delivery methods have shown a significant impact on enhancing drug delivery efficiency and reducing drug side effects. While various stimuli have been used to promote the drug delivery process, applying ultrasound (US) waves to control drug particles through the human body, noninvasively, has drawn the scientist's attention. However, microcarriers delivery reaches the aneurysmal artery by US waves that exert volumetric forces on blood, and drug carriers, which can therefore affect blood flow patterns and movement pathways of drug carriers, have not yet been studied. In this study, we developed a 3-D patient-specific model of abdominal aortic aneurysm (AAA) to evaluate the...
Green metal-organic frameworks (MOFs) for biomedical applications
, Article Microporous and Mesoporous Materials ; Volume 335 , 2022 ; 13871811 (ISSN) ; Atarod, M ; Tavakolizadeh, M ; Asgari, S ; Rezaei, M ; Akhavan, O ; Pourjavadi, A ; Jouyandeh, M ; Lima, E. C ; Hamed Mashhadzadeh, A ; Ehsani, A ; Ahmadi, S ; Saeb, M. R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
Metal-organic frameworks (MOFs), known as highly ordered crystalline hybrid structures, are the products of coordination polymerization of transition metals and organic ligands. MOFs are best known for their extensive specific surface area, hierarchically porous and tailorable 1D, 2D, or 3D micro-and nanostructure, and acceptable biocompatibility. Because of the multiplicity of metallic and organic units used in MOFs synthesis, tailor-made MOFs can be synthesized to be served as building blocks of advanced biological materials and systems. Recently, synthesis of green MOFs has received much more attention for nanobiomedicine usage. We review herein synthesis and biomedical application of...
Model Systems for Oxygen – Evolving Complex in Photosystem II: Manganese Oxides and Manganese Complexes with O and N Donor Ligands
, Ph.D. Dissertation Sharif University of Technology ; Mohammadi Boghaei, Davar (Supervisor)
Abstract
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,...
Synthesis of Azacrown Ethers N2O2 Ligands Substituted on the Ullerene and Investigation of Its Coordination Properties
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
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...
(Synthesis and Comparative Study on Complexation of OxNy-Azacrown Macrocyclic Ligands with [60] Fullerene and Cu(II
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
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...
Synthesis and Characterization of Cis-dioxomolybdenum(VI) Complex with an ONOtype Tridentate Schiff base Ligand and its Application as a Catalyst for Epoxidation of Olefinsin Water
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
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...
Synthesis of Tweezer-Like OxNy Macrocyclic Ligands and Study on the Effect of Macroring Linking on Selectivity Towards [60]Fullerene and Transition Metal Cations
, Ph.D. Dissertation Sharif University of Technology ; Ghanbari, Bahram (Supervisor) ; Bagherzadeh, Mojtaba (Co-Advisor)
Abstract
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...
Synthesis of Azacrown Macrocyclic Ligand with Pendant Arms and Study of Their Complexation with [60] Fullerene and Cu(II) Cation
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
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...
Enhanced Performance of Modified Pd/AL2O3 Catalysts by Triphenyl phosphine Ligand in Acetylene Selective Hydrogenation
, M.Sc. Thesis Sharif University of Technology ; Khorasheh, Farhad (Supervisor) ; Takht Ravanchi, Maryam (Supervisor)
Abstract
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...
Synthesis of Mo-Complex with An Ionic Salen Ligand and Its Application in Catalytic Epoxidation of Olefins and Sulfide Oxidation
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
In this project synthesis and characterization of a novel dioxomolybdenum(VI), with tetradentates Schiff base ligand which was soluble in water. The first step of complex synthesis was chloromethylation of salicylaldehyde and the second step was the reaction with the pyridine. After that salen ligand will be synthesized by reaction with ethylene diamine. In the presence of Mo(acac)₂(VI) the final product will be synthesized. The complex was characterized by spectroscopic methods such as UV, NMR, FT-IR and CHN. The synthetized complex was studied for olefin (aliphatic and aromatic) epoxidation as well as sulfide oxidation. It was more active in aliphatic olefins epoxidation than sulfide...
Electrochemical Study on Multidentate Amino Acid Ligands and Their Co(II) and Fe(III) Complexation
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
In our previous work, we have been undertake complexion of new amino phenolic ligand with Fe(III) and Co(II) in order to synthesis LSCF - and LSF - type perovskite inorganic membranes. In this study, the interactions between Co(II) and Fe(III) cations and the mentioned ligands were investigated their by cyclic voltammetry technique. In aqueous solution, it was found that chelate ring size has more prominent effect on the ligand-metal interaction than the related amino acid substitution. Accordingly, the amino phenol substituted...
Synthesis and Characterization of a New Metallomacrocycle Complex of Au(I) Containing 4,4ˊ-Azopyridine Ligand
, M.Sc. Thesis Sharif University of Technology ; Jamali, Sirous (Supervisor)
Abstract
Gold(I) complex of [Au2(μ-PAnP)Cl_2] (1) (PAnP = 9,10-bis(diphenylphosphino)anthracene) has been prepared from the reaction of AuCl(SMe2) with PAnP in a 2:1 molar ratio. The structure of 1 was determined using 1H NMR and 31P{1H} NMR spectroscopy in solution. The tetranuclear metallomacrocycle [Au4(μ-PAnP)2 (μ-4,4 AzoPy)2]OTf4 (2) (4,4 AzoPy = 4,4-Azopyridine) has been prepared from the reaction of complex 1 with AgOTf and 4,4-Azopyridine in a 1:2:1 molar ratio. The structure of 2 was characterized using X-ray crystallography in solid state, 1H NMR and 31P{1H} NMR spectroscopy, UV-Vis spectroscopy and photoluminescence spectroscopy in solution state. The 1 has bright green emission in solid...
Organoplatinum(ii) complexes containing chelating or bridging bis(N-heterocyclic carbene) ligands: Formation of a platinum(ii) carbonate complex by aerial CO2 fixation
, Article Dalton Transactions ; Volume 40, Issue 37 , Jun , 2011 , Pages 9362-9365 ; 14779226 (ISSN) ; Milić, D ; Kia, R ; Mazloomi, Z ; Abdolahi, H ; Sharif University of Technology
2011
Abstract
The preparation of two new bis(N-heterocyclic carbene) platinum(ii) complexes, in which NHC rings are joined by a CH2 linker group, is described. While, the chelate complex [PtMe2(bis-NHC1)], 1, was formed with large tert-butyl wingtips, the iso-propyl N-substituent analogue favors formation of the cluster complex [Pt2Me4(μ- SMe2)(μ-bis-NHC2)]2(μ-Ag2Br2), 2, in which two binuclear platinum(ii) complexes are linked together by an Ag2Br2 unit. The chelating platinum complex 1 undergoes aerial CO2 fixation and forms platinum(ii) carbonate complex [Pt(CO3)(bis-NHC1)], 3
Spectroscopic evidence on improvement in complex formation of O2N2 aza-crown macrocyclic ligands with Cu(II) acetate upon incorporation with [60]fullerene
, Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 169 , 2016 , Pages 202-207 ; 13861425 (ISSN) ; Gholamnezhad, P ; Sharif University of Technology
Elsevier B.V
2016
Abstract
The present paper reports the spectroscopic investigations on the complexation of Cu(II) with two macrocyclic ligands bonded to [60]Fullerene (L1 and L2) measured in N-methylpyrrolidone (NMP) as solvent. On the basis of UV–vis-NIR spectroscopy applying Jobs method of continuous variation, typical 1:1 stoichiometries were established for the complexes of Cu(II) with L1, and L2. DFT calculations suggested that superior HOMO distributions spread over the nitrogen-donor (as well as somehow oxygen- donor in L2) groups of L1 and L2 macrocycles were the key factor for the observed Kb value enhancement. Thermodynamic stabilities for these complexes have also been determined employing...
Synthesis and characterization of a new group of Exo-coordinating o2n2-donor macrocycles
, Article Australian Journal of Chemistry ; Volume 69, Issue 3 , 2016 , Pages 273-278 ; 00049425 (ISSN) ; Safarkoopayeh, B ; Kia, R ; Raithby, P.R ; Sharif University of Technology
CSIRO
2016
Abstract
The reaction of 15-18 membered benzodiazacrown ethers with salicylaldehyde afforded n-membered O2N2-donor macrocyclic ligands mounted with 1,3-diazacyclohexane subrings (1-4) in high yields. The products were characterized by FT-IR, 1H, 13C NMR spectroscopy, elemental analyses, and single crystal X-ray studies. The solid state structures revealed strong intramolecular hydrogen bonding between the pendant phenolic group and the tertiary nitrogen of the corresponding macroring
Non-covalent sulfoxide⋯(nitrosyl group) interactions involving coordinated nitrosyl in a Ru(ii) nitrosyl complex with an α-diimine ligand: Structural and computational studies
, Article CrystEngComm ; Volume 22, Issue 44 , October , 2020 , Pages 7532-7537 ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
Investigation of the X-ray structure of the newly prepared [Ru(NO)(2,6isopPh2Aceq)Cl3] (2,6isopPh2Aceq = bis(2,6-diisopropylphenylimino)acenaphthenequinone) complex revealed for the first time the π-hole interaction involving the coordinated nitrosyl group with DMSO as the solvent of crystallization in the crystal lattice. Processing of CSD data showed only one reported structure. A significant feature of the structure is the presence of n → π∗, π → σ∗, and n → σ∗ interactions due to the coordinated nitrosyl and chloro groups and DMSO. © 2020 The Royal Society of Chemistry
Supramolecular assembly through intermolecular n → π∗ interactions through a coordinated perrhenate formed: Via superoxidation of Re(i) to Re(vii) in the formation of substituted Re(CO)3complexes bearing Diimine ligands
, Article CrystEngComm ; Volume 22, Issue 39 , September , 2020 , Pages 6448-6452 ; Taghavi, T ; Raithby, P. R ; Sharif University of Technology
Royal Society of Chemistry
2020
Abstract
We report the structural, spectroscopic, and computational studies of two new Re(i) tricarbonyl complexes bearing 2,3,6,7-tetraphenyl-1,4,5,8-tetraazaphenanthrene (Ph4TAP) and 4,5-diazafluoren-9-one (dafone) having a coordinated perrhenate group obtained via in situ superoxidation of Re(i) to Re(vii); intramolecular and intermolecular n → π∗ interactions are dominant and stabilize the molecular geometry and crystal packing. This journal is © The Royal Society of Chemistry
Structural, non-covalent interaction, and natural bond orbital studies on bromido-tricarbonyl rhenium(I) complexes bearing alkyl-substituted 1,4-diazabutadiene (DAB) ligands
, Article Crystals ; Volume 10, Issue 4 , April , 2020 ; Kalaghchi, A ; Sharif University of Technology
MDPI AG
2020
Abstract
The synthesis, characterization, structural and computational studies of Re(I) tricarbonyl bromo complexes bearing alkyl-substituted 1,4-diazabutadiene ligands, [Re(CO)3(1,4-DAB)Br], where 1,4-DAB = N,N-bis(2,4-dimethylbenzene)-1,4-diazabutadiene,2,4-Me 2DAB (1); N,N-bis(2,4-dimethylbenzene)-2,3-dimethyl-1,4-diazabutadiene,2,4-Me 2DABMe (2); N,N-bis(2,4,6-trimethylbenzene)-1,4-diazabutadiene,2,4,6-Me 3DAB (3); and N,N-bis(2,6-diisopropylbenzene)-1,4-diazabutadiene,2,6-ipr 2DAB (4) are reported. The complexes were characterized by different spectroscopic methods such as FT-IR,1 H-NMR,13C-NMR, and elemental analyses and their solid-state structures were confirmed by X-ray diffraction. In each...