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Synthesis and Study of Catalytic Activity of Iron (III)-bis(2-oxazolinyl) Methane complex by Urea Hydrogen Peroxide in Oxidation of Sulfides
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
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,...
Synthesis, Characterization, Structural and Theoretical Studies of Some New Homoleptic and Heteroleptic Diiminic and Diphosphine Copper(I) Complexes
, M.Sc. Thesis Sharif University of Technology ; Kia, Reza (Supervisor)
Abstract
In this study first some new diimine ligands were synthesized, then mononuclear and binuclear Cu(I) complexes with starting matrials, [Cu(NCCH3)4]X (X= PF6, ClO4) or CuI, and the synthesized diimine ligands and phosphinic (POP) ligand were prepared. These complexes were characterized using 1HNMR, 31P{1H}NMR, and FT-IR spectroscopic methods and their solid state structure were determined by single crystal X-ray diffraction. Inspection of the solid-state structurs, showed variety of the stabilizing interactions shuch as NO2•••NO2, π•••π, C─H•••π, and NO2•••π. Density functional theory (DFT) was used for geometry optimization of the singlet states in gas phase and the electronic structure...
Highly efficient aerobic epoxidation of cyclic olefins in mild conditions by a novel binuclear manganese(II) complex containing N-(4-nitrophenyl)picolinamide ligand
, Article Catalysis Communications ; Volume 65 , May , 2015 , Pages 72-75 ; 15667367 (ISSN) ; Ghanbarpour, A ; Khavasi, H. R ; Sharif University of Technology
Elsevier
2015
Abstract
A novel binuclear Mn(II) complex based on a para-nitro substituted amidic ligand (N-(4-nitrophenyl)picolinamide) has been synthesized and characterized by X-ray crystallography. This complex shows a high degree of conversion and epoxide selectivity in Mukaiyama aerobic epoxidation reactions of cyclic olefins in mild conditions
Nano CoCuFe2O4 catalyzed coupling reaction of acid chlorides with terminal alkynes: A powerful toolbox for palladium-free ynone synthesis
, Article Catalysis Communications ; Volume 102 , 2017 , Pages 71-75 ; 15667367 (ISSN) ; Pourkaveh, R ; Ahangarpour, M ; Sharif University of Technology
Elsevier B.V
2017
Abstract
The present work describes the application of nano CoCuFe2O4 toward the coupling reaction of acyl chlorides with terminal alkynes. By this catalytic system, ynone derivatives were formed in high yields via a palladium-free strategy. This protocol avoids the use of phosphine ligands as well as toxic CO sources. Recovery of catalyst by employing an external magnetic field and its reuse up to 9 consecutive trials confirm the robustness of this catalytic system. © 2017 Elsevier B.V
Ligand modifications for tailoring the binuclear microenvironments in schiff-base calixpyrrole pacman complexes
, Article Inorganic Chemistry ; Volume 48, Issue 15 , 2009 , Pages 7491-7500 ; 00201669 (ISSN) ; Devoille, A. M. J ; Boghaei, D. M ; Slawin, A. M. Z ; Love, J. B ; Sharif University of Technology
2009
Abstract
The synthesis and structures of two new octadentate, Schiff-base calixpyrrole macrocycles are presented in which modifications at the meso-substituents (L1) or the aryl spacer between the two pyrrole-imine donor compartments (L2) are introduced. The outcomes of these changes are highlighted in the structures of binuclear Pacman complexes of these macrocycles, [M2(L1)] and [M2(L 2)]. Both palladium and cobalt complexes of the fluorenylmeso- substituted macrocycle H4L1 adopt rigid, but laterally twisted geometries with enclosed bimetallic microenvironments; a consequence of this spatial constraint is an exo-exo-bonding mode of pyridine in the dicobalt complex [Co2(py)2(L1)]. In contrast, the...
Evolution of 'ligand-deffusion chreodes' on protein-surface models: A genetic-algorithm study
, Article Chemistry and Biodiversity ; Volume 4, Issue 12 , 2007 , Pages 2766-2771 ; 16121872 (ISSN) ; Kargar, M ; Katanforoush, A ; Abolhassani, H ; Sadeghi, M ; Sharif University of Technology
2007
Abstract
Lattice models have been previously used to model ligand diffusion on protein surfaces. Using such models, it has been shown that the presence of pathways (or 'chreodes') of consecutive residues with certain properties can decrease the number of steps required for the arrival of a ligand at the active site. In this work, we show that, based on a genetic algorithm, ligand-diffusion pathways can evolve on a protein surface, when this surface is selected for shortening the travel length toward the active site. Biological implications of these results are discussed. © 2007 Verlag Helvetica Chimica Acta AG, Zürich
Synthesis of N2O2N Azacrown Macrocyclic Ligands and Comparative Study on the Complexation of Ligands with [60]Fullerene and Cu(II)
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
By considering previous experiments undertaken in our laboratory on O2Nx (x=2,3) azacrown complexes with [60]fullerene, it was found that factors such as the macroring size, type and number of the donors groups in these macrocyclic ligands had significant effects on their selectivity towards [60]fullerene complexation. In this research, three N2O2N–azacrown macrocyclic ligand having uniform distribution of nitrogen atoms in macroring was synthesized using direct synthesis and high dilution method. The products were characterized applying 1H and 13C NMR spectroscopy as well as elemental analysis. Interaction of these ligands with [60]fullerene and Cu(II) were monitored by UV-vis spectroscopy...
Synthesis and Study of Coordination Properties of Axial Ligands Pendant to Fullerene C60
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
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...
Oxidation of sulfides with urea-hydrogen peroxide catalyzed by iron-salen complexes
, Article Journal of Sulfur Chemistry ; Volume 32, Issue 4 , 2011 , Pages 335-343 ; 17415993 (ISSN) ; Zare, M ; Sharif University of Technology
2011
Abstract
The oxidation of sulfides to sulfoxides with hydrogen peroxide in good yield and high selectivity has been catalyzed very effectively by a series of Schiff base salen-type iron complexes in a monophasic medium (CH 2Cl2/CH3OH) at ambient temperature. The results of the present study show that the reaction rate strongly depends on both catalyst steric effects and steric and electronic properties of sulfides. In the system, the electronic spectral studies are applied to explain the formation of a reactive (salen) Fe=O intermediate
Granulated copper oxide nano-catalyst: A novel and efficient catalyst for C-N cross-coupling of amines with iodobenzene
, Article Monatshefte fur Chemie ; Volume 142, Issue 8 , 2011 , Pages 801-806 ; 00269247 (ISSN) ; Sadjadi, S ; Hosseinpour, M ; Abdollahi, M ; Sharif University of Technology
Abstract
Nano-structured CuO granules catalyze the C-N cross-coupling of amines with iodobenzene in excellent yields. The reaction is simple, efficient, and operates in air under ligand-free conditions
Synthesis, structure characterization and study of a new molybdenum schiff base complex as an epoxidation catalyst with very high turnover numbers
, Article Inorganic Chemistry Communications ; Volume 84 , 2017 , Pages 63-67 ; 13877003 (ISSN) ; Ataie, S ; Mahmoudi, H ; Janczak, J ; Sharif University of Technology
Abstract
The reaction between [MoO2(acac)2] and an ONO type Schiff-base ligand (L = 4-bromo-2-((2-hydroxy-5-methylphenylimino)methyl)phenol) resulted a new oligomer molybdenum complex ([MoO2(L)]n). The oligomer complex was characterized by elemental analysis, FT-IR, 1H and 13C NMR spectroscopies. A suitable single crystal of the complex was grown in DMSO and characterized by X-ray single crystal diffraction as monomer stabilized by one DMSO molecule, [MoO2L(DMSO)]. The [MoO2(L)]n complex was used as a catalyst in epoxidation of olefins. Besides the high activity and selectivity, very high turnover numbers were a remarkable advantage of the catalytic system. © 2017
Two new copper(II) complexes with chelating N,O-type bidentate ligands: synthesis, characterization, crystal structure and catalytic activity in azide–alkyne cycloaddition reaction
, Article Inorganica Chimica Acta ; Volume 466 , 2017 , Pages 398-404 ; 00201693 (ISSN) ; Bayrami, A ; Kia, R ; Amini, M ; Kershaw Cook, L. J ; Raithby, P. R ; Sharif University of Technology
Abstract
Tetra-coordinated 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, ligands with copper acetate, respectively. The complexes were characterized using FT-IR spectroscopy, elemental analyses, and their solid state structures were confirmed by single crystal X-ray diffraction. The catalytic activity of the complexes was evaluated in one-pot azide–alkyne cycloaddition (AAC) click reaction in water without need of any additional agent. The [CuL2] complex showed high catalytic activity in this reaction and 1,2,3-triazole derivatives were produced in moderate to good...
Supramolecular dyad derived from a buckybowl series of O2N2-donor naphthodiaza-crowns coordinated to C60: photophysical, NMR and theoretical studies
, Article Supramolecular Chemistry ; Volume 29, Issue 4 , 2017 , Pages 248-258 ; 10610278 (ISSN) ; Zarepour jevinani, M ; Sharif University of Technology
Taylor and Francis Ltd
2017
Abstract
Supramolecular complexation of C60 with L1-L5 were studied in toluene, chloroform and 1,2-dichlorobenzene solvents using UV–vis, fluorescence, 1H, 13C NMR spectroscopy as well as density functional theory (DFT) calculations. The Job’s plot of continuous variation method established 1:1 stoichiometry for L1-L5/C60. Binding constants (K) calculated for L1-L5/C60 were also determined employing UV–vis and fluorescence spectroscopy. Both steady-state and time-resolved fluorescence spectroscopic surveys showed remarkable fluorescence quenching phenomenon for L1-L5 in the presence of C60 which was primarily attributed to involvement of a static process. The observed fluorescence quenching in L1–L5...
Morphology modification of the iron fumarate MIL-88A metal–organic framework using formic acid and acetic acid as modulators
, Article European Journal of Inorganic Chemistry ; Volume 2018, Issue 18 , 2018 , Pages 1909-1915 ; 14341948 (ISSN) ; Zebarjad, S. M ; Madaah Hosseini, H. R ; Sharif University of Technology
Wiley-VCH Verlag
2018
Abstract
Metal–organic frameworks (MOFs) are best known for their great structural diversity. The uniformity in the properties of MOFs is mainly governed by the size and morphology of the particles. In the present research, iron-MIL-88A was prepared by a modulator-assisted solvothermal method, and the role of modulating agents in the formation process of MOF particles was investigated. Acetic acid and formic acid were chosen as monoligand modulating agents. The changes in morphology and size distribution of the products were scrutinized by using SEM micrographs. Both modulators clearly interfered with the crystallization process through their attachment to the reactive sites. At low modulator...
Synthesis, X-ray structure and study of a mixed ligand iron(III) complex with tridentate Schiff base as a homogeneous catalyst in the efficient oxidation of sulfides
, Article Inorganic Chemistry Communications ; Volume 12, Issue 6 , 2009 , Pages 476-480 ; 13877003 (ISSN) ; Tahsini, L ; Latifi, R ; Amani, V ; Ellern, A ; Keith Woo, L ; Sharif University of Technology
2009
Abstract
A mononuclear mixed ligand complex of iron, [FeIII(N-OPh-sal)(acac)EtOH], where Hacac and N-HOPh-Hsal denote acetylacetone and N-hydroxyphenyl-salicylideneamine, respectively, has been synthesized and characterized by elemental analysis, spectral studies and X-ray crystallography. The catalytic system containing this complex and urea hydrogen peroxide as oxidizing agent was used to selectively oxidize a range of sulfides to the corresponding sulfoxides in good yields under mild conditions. The electronic spectra of the catalytic system were applied to explore reactivity and stability of the catalyst during sulfide oxidation reactions and to examine the nature of active species, as well. ©...
Catalytic oxidation of sulfides to sulfoxide using manganese(III) complexes with bidentate O,N-donor oxazoline ligand and UHP oxidizing agent
, Article Catalysis Communications ; Volume 10, Issue 2 , 2008 , Pages 196-200 ; 15667367 (ISSN) ; Latifi, R ; Tahsini, L ; Amini, M ; Sharif University of Technology
2008
Abstract
The efficient catalytic systems were investigated for the oxidation of various sulfide by manganese(III)-oxazoline complexes, [Mn(phox)2(MeOH)2]ClO4 and Mn(phox)3 (Hphox = 2-(2′-hydroxyphenyl)oxazoline). These complexes were found efficient catalysts for the oxidation of sulfides with urea hydrogen peroxide (UHP) in short reaction times (5 min) and under mild condition. Sulfoxides were obtained as the main products together with variable amounts of sulfones. The efficiency of the catalytic system was strongly influenced by the nature of solvents and axial ligands so the best yields were achieved in a mixture of methanol: dichloromethane and in the presence of imidazole as co-catalyst. © 2008...
Synthesis, characterization, electrochemical studies and catecholase-like activity of dinuclear copper(II) complexes of a phenol-based compartmental ligand
, Article Journal of Coordination Chemistry ; Volume 60, Issue 21 , 2007 , Pages 2283-2295 ; 00958972 (ISSN) ; Gharagozlou, M ; Sayadi, M ; Sharif University of Technology
2007
Abstract
The new dinuclear copper(II) complexes, Cu(II)M(II) (M = Mn, Co, Ni, Cu), of a phenol-based compartmental ligand, having dissimilar N(amine)2O2 and N(imine)2O2 coordination sites have been synthesized. In this system there are two different compartments, one has piperazinyl nitrogens and phenolic oxygens and the other compartment has meso-stilbenediamine nitrogens and phenolic oxygens as coordinating sites. The complexes were characterized by elemental analysis, IR and electronic spectra as well as conductivity measurements. Dinuclear complexes were prepared through the CuIIPbII precursor complex by transmetalation of the Pb(II) for the M(II) ion. The electrochemistry and catecholase-like...
Synthesis, characterization and fluorescence spectra of mixed ligand Zn(II), Cd(II) and Hg(II) complexes with 1,10-phenanthroline-5,6-dione ligand
, Article Journal of Coordination Chemistry ; Volume 60, Issue 15 , 2007 , Pages 1629-1635 ; 00958972 (ISSN) ; Behzadian Asl , F ; Sharif University of Technology
2007
Abstract
The novel mixed ligand complexes [M(bpy)(phen-dione)](PF6)2 (M = Zn(II), Cd(II) and Hg(II), bpy = 2,2′-bipyridine and phen-dione = 1,10-phenanthroline-5,6-dione) have been synthesized and characterized by elemental analysis, IR, 1H NMR and electronic absorption spectroscopies. The ν(C=O) of coordinated phen-dione in these complexes are very similar to the free phen-dione ligand showing that phen-dione is not coordinated to metal ion from its C=O sites. Absorption spectra of the complexes show two absorption bands for intraligand transitions. These absorption bands show dependence to the dielectric constant of solvent. These complexes exhibit an intensive fluorescence band around 535 nm in...
Synthesis, characterization and fluorescence spectra of mononuclear Zn(II), Cd(II) and Hg(II) complexes with 1,10-phenanthroline-5,6-dione ligand
, Article Journal of Coordination Chemistry ; Volume 60, Issue 3 , 2007 , Pages 347-353 ; 00958972 (ISSN) ; Behzadian Asl, F ; Sharif University of Technology
2007
Abstract
The mononuclear complexes of Zn(II), Cd(II) and Hg(II), [Zn(phen-dione)Cl2], [Cd(phen-dione)Cl2] and [Hg(phen-dione)Cl2], where phen-dione = 1,10-phenanthroline-5,6-dione, have been synthesized and characterized by elemental analysis and IR, 1H NMR and electronic absorption spectroscopies. The ν(C=O) of coordinated phen-dione ligands in these complexes shows that the phen-dione is not coordinated to metal ion from its C=O sites. Electronic spectra of the complexes show two absorption bands for intraligand transitions. These absorption bands show dependence on the dielectric constant of solvents. These complexes exhibit an intense fluorescence band around 545 nm in DMSO when the excitation...
Prediction of Protein Ligand Binding Affinity Using Deep Networks
, M.Sc. Thesis Sharif University of Technology ; Kalhor, Hamid Reza (Supervisor) ; Motahhari, Abolfazl (Co-Supervisor)
Abstract
Protein-ligand binding affinity is extremely important for finding new candidates in drug discovery and computational biochemistry. One of the physical characteristics for protein ligand interactions has been dissociation constant (KD) which can be obtain experimentally. However, there have been tremendous efforts to predict KD using modeling and computational approaches for protein-ligand interactions. In this project, we have exploited Convolutional Neural Network (CNN) model based on KDeep design, PDBBind version 2016 refined set training data, and examining it with KDeep core set test data. In order to modify KDeep,instead of 24 rotations (0, 90, 180 and 270 degrees in selection of two...