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Comparative Study on [60]Fullerene and Cu(II) Complexation with O2N3-Azacrowns
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
The purpose of this project is to synthesis of O2N3-azacrown ligands with 17 to 21 membered ring and investigation of their interaction with C60 according to increase ring size. These macrocyclic ligands can be used in C60 purification. In this project, change in macrocyclic cavity for finding the best macrocycle with appropriate cavity to C60 size has been considered. Firstly, five O2N3-azacrown ligands were synthesized and characterized by NMR spectroscopy and elemental analysis. Interaction of these ligands were considered by electronic spectroscopy applying Benesi-Hildebrand equation. According to the results, it was found that the best macrocycle for formation of stable complex with...
Structural relevance of N2 O2 -donor naphthodiaza-crown macrocyclic ligands to selective fluorescence signaling behavior towards aliphatic tertiary amines
,
Article
Journal of Photochemistry and Photobiology A: Chemistry
;
Volume 314
,
2016
,
Pages 42-51
;
10106030 (ISSN)
; Zarepour Jevinani, M
;
Sharif University of Technology
Elsevier
2016
Abstract
A series of N2 O2 -donor naphthodiaza-crown macrocyclic ligands, L1 -L5 , were synthesized and characterized by IR, 1H and 13C NMR spectroscopy, mass spectrometry as well as microanalysis. Preliminary observations employing UV-vis spectrophotometry of L3 in ethanol revealed that triethylamine (TEA) has a significant blue-shift effect on the entire of the spectra. Then, the detection of aliphatic and aromatic amines by L3 were followed by monitoring of fluorescence quenching of the resulting adducts in terms of their binding with L1 -L5 . Both steady-state and time-resolved spectroscopic measurements in the...
Synthesis, single crystal, electrochemical and study of fluorogenic dibenzodiaza-crown-appended with bis(ZnTPP) azo-tweezer and spectroscopic elucidation of photo-induced macrocycle-deformation-based chromotropism
, Article Polyhedron ; Volume 227 , 2022 ; 02775387 (ISSN) ; Mahdavian, M ; Bakhshandeh, M ; Kubicki, M ; Sharif University of Technology
Elsevier Ltd
2022
Abstract
In the present research, a new tweezer T bearing azobenzene linker 1 was prepared, characterized by applying FT-IR spectroscopy, fluorescence spectroscopy, UV–visible spectroscopy, and elemental analysis 1H and 13C{1H} NMR. T crystals were obtained by reaction of 1 with ZnTPP in CHCl3/acetone. Under irradiation with a mercury lamp to achieve the trans-to-cis isomerization, a dramatic color change from violet to green in chloroform was observed. The X-ray crystallography of T revealed an observable macroring deformation of the ZnTPP for the trans isomer. We observed a deviation of 0.11 Å from planarity for the least-squares plane of ZnTPP owing to the axial coordination by the pyridine...
Synthesis and thermogravimetric analysis of inclusion complexes of O2N2-donor Aza-crown macrocyclic ligands with [60]fullerene
, Article Journal of Thermal Analysis and Calorimetry ; Volume 118, Issue 3 , 2014 , pp 1631-1637 ; ISSN: 13886150 ; Gholamnezhad, P ; Hatami, M ; Sharif University of Technology
Abstract
A simple method for the formation of inclusion complex of [60]fullerene with two O2N2-donor aza-crown macrocyclic ligands was introduced. The products were characterized using UV-vis and IR spectroscopies as well as HPLC, and ESI mass spectrometry. The ESI mass and elemental analysis data revealed that the ratio of macroring:[60]fullerene were not the same. The binding capability of the macrorings as well as the number of the macroring addends to [60]fullerene were investigated using thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). Considering percentage mass loss in different steps of TG and the enthalpy changes in DSC found for each of these products, the number...
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...
Study on Cation and Fullerene Recognition by OxNx-Aza Crown Macrocyclic Ligands
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
In this research, a new group of N2O2–azacrown macrocyclic ligands with different macroring size from 15 to 18 was synthesized using one-pot facile and high yield reaction. The products were characterized applying FT-IR, 1H and 13C NMR spectroscopies as well as elemental analysis. The single crystal structure of 18-membered macrocyclic ligand was also determined by x-ray crystallography. The crystallographic data showed such strong inter-molecular hydrogen bonding which excluded their nitrogen-donor groups, and initial investigation with UV-Vis spectroscopy shows no intraction with [60]fullerene, despite of presence of these interacrtions in their parent macrocycles. The result of Job’s...
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...
Coordination Investigation of Macrocyclic Ligands Tertiary Amine Groups with [60] Fullerene and Cu(II)
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
The reaction of O2N2-donor naphthodiazacrown, with salicylaldehyde afforded new O3N2-donor macrocyclic ligands (L1-3naph) mounted with 1,3-diazcyclohexane subring in high yield. The product was characterized by IR, 1HNMR spectroscopy as well as elemental microanalysis and single crystal X-ray studies (just for L3naph). The interactions of [60]fullerene in presence and absence of base, Cu(II), Hg(II) and Zn(II) with L1-3naph were investigated employing fluorescence spectroscopy. The efficient fluorescence quenching of L1-3naph in presence of C60, Cu(II)( L1-2naph) and the fluorescence enhancement in presence of Hg(II) and Zn(II) indicated that the interaction with [60]fullerene Hg(II) and...
Synthesis and Characterization of NxOy-Naphthodiazacrowns and Study of Supramolecular Chemistry with C60 and Cu(II)
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
New N4O6 molecular tweezers were synthesized from N2O2 benzo- and naphthodiazacrown macrocycles bearing benzylic dialdehydes as a flexible and semi-flexible spacer in a short time and at room temperature. The products were characterized by IR, 1H and 13C NMR spectroscopy as well as elemental microanalysis. The interactions of some of these tweezers with C60, Cu(II), Co(II), Ni(II), Zn(II), Hg(II) and Mn(II) were investigated by employing UV-Vis and fluorescence spectroscopy. Efficient fluorescence responses for 2NM3BD were observed in the presence of C60, Cu(II), Mn(II), Hg(II) and Zn(II). Meanwhile, the calculation of the association constants (K¬BH) employing Benesi-Hildebrand equation in...
Synthesis and photoisomerization study of new aza-crown macrocyclic tweezer tethered through an azobenzene linker: the first report on supramolecular interaction of azobenzene moiety with C60
, Article Journal of Molecular Structure ; Volume 1144 , 2017 , Pages 360-369 ; 00222860 (ISSN) ; Mahdavian, M ; García Deibe, A. M ; Sharif University of Technology
Abstract
In the present communication, three bimacrocyclic tweezers linked through azobenzene moiety, Ln (n = 1–3) were synthesized in a multistep route and characterized by x-ray crystallography, IR, 1H and 13C NMR, UV–vis spectroscopy as well as CHN microanalysis. UV–visible spectroscopy established that the irradiation of L1 and L3 with UV light promoted the trans to cis isomerization. Irradiating the reaction mixtures with Hg lamp, significant supramolecular interactions between L1 and L3 with C60 were also found in terms of the association constants calculated by UV–visible spectroscopy, denoting on more pronounced interaction with C60 that in the absence of UV light. The molecular structures of...
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...
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...
Novel pillar[5]arenes show high cross-sensitivity in pvc-plasticized membrane potentiometric sensors
, Article Chemosensors ; Volume 10, Issue 10 , 2022 ; 22279040 (ISSN) ; Yemisci, E ; Kursunlu, A. N ; Kirsanov, D ; Sharif University of Technology
MDPI
2022
Abstract
In this study a variety of novel symmetrically and asymmetrically functionalized pillar[5]arenes were synthesized, structurally characterized and applied as ionophores in PVC-plasticized membrane potentiometric sensors. During the sensitivity studies it was found that these novel sensors demonstrate pronounced cationic response towards different metal ions in aqueous solutions. A selectivity evaluation revealed that the developed sensors do not possess sharp preferences to particular ions, but offer a broad cross-sensitivity and can be employed in potentiometric multisensor systems. © 2022 by the authors
Study on The Effect of Complex Formation of Pyridine-derivatized Aza-crown Macrocyclic Ligands Towards Zinc Tetraphenylporphyrin and Zinc Phthalocycnine, Cu(Ii) Cation and C60
, Ph.D. Dissertation Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
A set of azacrown macrocyclic ligands bearing pyridine moiety (bp, 1p, 2p) were synthesized and characterized by single-crystal X-ray diffraction (SCXRD), elemental analysis, FT-IR, 1H and 13C NMR methods. The complexes of zinc tetraphenylporphyrin (ZnTPP) with the bp and 1p as the axial ligand were synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, IR, 1H and 13C NMR, fluorescence, UV-vis, cyclic voltammetry, together with TD DFT calculations. By employing this method for ZnTPPbenz and ZnTPPH complexes elucidated that the pyridine moiety was bonded through the fifth- coordination site on the zinc metal atom. In the following study, the coordination...
Insight into the Coordination Varieties of a NxO2 Peraza-Crown Macrocyclic Ligand Group Anchored by Pyridine Side Arms
, Ph.D. Dissertation Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
In this treatise, the effect of type of macrocycle ring on the final structure of the complexes which made from them was investigated. For this purpose, by changing the 15-membered benzylic macrocycle with two pyridine pendant arms (2p), which was studied in our previous experiments (the effect of the position of the nitrogen atom of the pyridine ring in the side arm and the type of metal ion in the geometry of its complexes), two new macrocycles by adding a naphthalene rings instead of benzylic ringsin in 2p and increasing the ring size from 15 to 17 members, Lpy-naph and Lpy-benz were symthesized respectively. The molecular formula and structure of Lpy-naph and Lpy-benz were confirmed by...
Comparative study on the effect of nitrogen-donor groups versus macro-ring size in O2Nx-azacrowns on the complexation with [60]fullerene
, Article Fullerenes Nanotubes and Carbon Nanostructures ; Vol. 22, issue. 4 , 2014 , pp. 322-331 ; ISSN: 1536383X ; Mahloojy, N ; Sharif University of Technology
Abstract
The interaction of [60]fullerene with a newly synthesized series of 17-to 21-membered macrocyclic ligands containing an O2N3-donor set has been investigated. The formation constants (K) arising from their complexation with [60]fullerene macrocycles, having various ring size, were measured in CHCl3 media by UV-visible spectroscopy applying Benesi-Hildebrand (BH) equation and their stoichiometries were also determined by the Job method. The best K value was measured for 20-membered ring macrocycle in which a 1:1 complexation stoichiometry with [60]fullerene was dominant. Furthermore, 1H NMR spectroscopy data reveled that the macrocylic ligand coordinates [60]fullerene via the nitrogen-donor...
Halide (Cl-, Br-, I-) influence on the electronic properties of macrocyclic nickel(II) complexes: Ab-initio DFT study
, Article Journal of the Korean Chemical Society ; Volume 57, Issue 3 , 2013 , Pages 311-315 ; 10172548 (ISSN) ; Akhtari, K ; Hassanzadeh, K ; Piltan, M ; Saaidpour, S ; Abedi, M ; Sharif University of Technology
2013
Abstract
The geometry structures of hexa-coordinated [NiLX]X complexes (X = Cl -, Br-, I-) {L = 8,9,18,19-tetrahydro-7H,17H- dibenzo[f,o] [1,5,9,13]dioxadiaza cyclohexadecine-8,18-diol} are optimized by density functional theory (DFT) using B3LYP/LANL2DZ. The calculated geometric parameters are in good agreement with the corresponding experimental values. Calculation results about these complexes show that dipole moment decreases, and the energy levels of HOMOs descend from iodo-complex to chloro-complex. The energy levels of HOMOs descend gently from iodo-complex to chloro-complex, while the energy levels of LUMOs in the present complexes are almost similar; therefore the energy gapes between HOMOs...
Photoluminescence emission enhancement and coordination-driven isomer-locking effects of Cr(III) on azobenzene-bearing tweezer anchored to binaphthdiaza-crown macrocycles
, Article Journal of Luminescence ; Volume 201 , 2018 , Pages 329-337 ; 00222313 (ISSN) ; Mahdavian, M ; Sharif University of Technology
Elsevier B.V
2018
Abstract
In this report, the synthesis of a new bi-macrocycle tweezer linked through an azobenzene moiety, L was undertaken. The characterization of the tweezer was accomplished by employing IR, 1H and 13C NMR, UV–vis, fluorescence spectroscopy and CHN microanalysis while the UV–visible spectroscopy illustrated a trans ⇆ cis photo-isomerization for L. According to our preliminary fluorescence observations, a metal-ion chemosensing behavior was established for trans-L isomer towards Cr(III) ion among the library metal ions. The quenching of the respective trans ⇆ cis isomerization in the presence of Cr(III) ion suggested the preference of a strong interaction between Cr(III) ion with L, leading to...
Synthesis and Study on Complexation of Naphthalene Azacrown Macrocycle Ligands with [60] Fullerene and Metal Cations Like Cu2+
, Ph.D. Dissertation Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
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...
Study of NxOy Macrocycles Bearing Peripheral Functional Groups as Axial Ligands of Zinc Tetraphenylporphyrin
, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram (Supervisor)
Abstract
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...