Loading...
Search for:
disulfide
0.007 seconds
Total 40 records
Oxidative Deprotection of Trimethylsilyl Ethers and Coupling of Thiols to Disulfides by Cr (VI) and Fe (III) Heterogeneous Nanocatalysts
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Reza (Supervisor) ; Rajabi, Fateme (Supervisor)
Abstract
Considering the advantages of heterogeneous catalysts for the easy work up procedure, being eco-friendly, and the reusability, herein, two projects are carried out by metal-supported SBA-15 catalysts. The first one is the oxidative deprotection of trimethylsilyl ethers catalyzed Cr (VI) in the presence of TBHP as oxidant. In this project, trimethylsylil ethers are oxidized in good to high yields. The second project is the oxidative coupling of thiols to disulfides catalyzed by Fe (III) in the presence of hydrogenperoxide. This catalyst/oxidant system convets different aromatic thiols to corresponding disulfides efficiently
Synthesis of Dithiocarbamate Derivatives and Their Applications to Prepare Heterocyclic Compounds
, M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Reza (Supervisor)
Abstract
Sulfur containing compounds are known as the most applicable group of organic compounds. Due to their medicinal and biological applications, dithiocarbamates are the most considerable among the many sulfur containing compounds. There are many procedures reported to synthesize these compounds as synthetic intermediates instead of thiophosgen and isothiocyanates. The reaction of amine and carbon disulfide is reported as the best and least hazardous way to synthesize this functional group. In this project heterocyclic compounds such as thiazoles, thiazolidine-2-thione, and 2-(alkylthio)thiazol-4(5H)-one derivatives were synthesized from the reaction of prepared dithiocarbamates with in situ...
Transport Properties in Heterostructures of 2D Layers of Graphene with WS2 and hBN Quantum Dots
, M.Sc. Thesis Sharif University of Technology ; Simchi, Abdolreza (Supervisor)
Abstract
Graphene based photodetectors which are modified with quantum dots, are the new generation of detectors. In these supplies an integration of graphene’s unique characteristics like high conductivity and mobility and the high light absorption of quantum dots, are used.In this research graphene by chemical vapor deposition in centimetric large scales, tungsten disulfide quantum dots, boron nitride and graphene quantum dots and 2D tungsten disulfide have been synthesized. In the next step each of them were characterized to modify the quality of used layers in heterostructure.Based on the characteristic tests, quantum dots aspect ratios were 1 to 5 nanometers. Also tungsten disulfide was obtained...
Synthesize and Characterization of 2D WS2 Nano-layers for Next Generation Optoelectronic Devices
, M.Sc. Thesis Sharif University of Technology ; Simchi, Abdolreza (Supervisor)
Abstract
Transition Metal Dichalcogenids (TMD) are types of 2D materials that exibit wide range of electronic, optical, mechanical, chemical, and thermal properties. These materials with MX2 general formula, have atract attentions with respect to their unusual properties because of their very limited dimensions. Their tunable properties and materials availibility make them attractive for wide range of applications. In recent years, chemical vapor deposition (CVD) methods are promising in preparing high quality TMD with scalable size, controllable thickness, and very excellent electronic properties. Also, chalenges are remaining in synthesis and transfering of TMD are difficulty for most of...
Synthesis and Characterization of 2D-WS2 Nanostructures for Gas Sensing Applications
, Ph.D. Dissertation Sharif University of Technology ; Iraji Zad, Azam (Supervisor) ; Mohammadpour, Raheleh (Supervisor)
Abstract
Nowadays, beside of two-dimensional tungsten disulfide nanosheets, its hybrid nanostructures also provide active sites for physisorption of gas molecules due to their high surface-to-volume ratio, surface active site (such as sulfur vacancies, surface defects, and p-n junctions) and active edges, and are very attractive for gas sensing applications. In this research, tungsten disulfide layered crystallines were grown by chemical vapor phase transport and its two-dimensional nanoflakes were prepared by liquid exfoliation method. So, a thin film of the nanoflakes was deposited on a silicon oxide substrate by drop casting method, and its gas sensing properties were investigated for water and...
An efficient one-pot Michael addition of dithiocarbamate anion to α,β-unsaturated olefins mediated by lithium perchlorate
, Article Journal of Sulfur Chemistry ; Volume 26, Issue 2 , 2005 , Pages 149-153 ; 17415993 (ISSN) ; Saidi, M. R ; Sharif University of Technology
Taylor and Francis Ltd
2005
Abstract
The reaction of substituted dithiocarbamates with electrophilic alkenes in the presence of LiClO4 was investigated in an attempt to prepare numerous ethyl dithiocarbamates bearing β-electron-withdrawing-group substituents. The reaction conditions are mild, neutral, with extremely simple work-up procedures, and offer high yield. © 2005 Taylor & Francis Group Ltd
Dithiocarbamate as an efficient intermediate for the synthesis of 2-(alkylthio)thiazol-4(5H)-ones
, Article Journal of Sulfur Chemistry ; Volume 37, Issue 5 , 2016 , Pages 529-536 ; 17415993 (ISSN) ; Alaei, M. A ; Soleymani Movahed, F ; Jomeh, N ; Saidi, M. R ; Sharif University of Technology
Taylor and Francis Ltd
Abstract
An effective approach for the synthesis of 2-(alkylthio)thiazol-4(5H)-ones from alkyl dithiocarbamates and chloroacetyl chloride in the presence of NaHCO3 has been developed. Good to excellent yields of products, simple reaction conditions and general applicability are the most important advantages of this protocol
A simple and novel eco-friendly process for the synthesis of cyclic dithiocarbonates from epoxides and carbon disulfide in water
, Article Journal of Heterocyclic Chemistry ; Volume 46, Issue 2 , 2009 , Pages 347-350 ; 0022152X (ISSN) ; Ebrahimi, F ; Azizi, N ; Saidi, M. R ; Sharif University of Technology
2009
Abstract
The reaction of oxiranes with carbon disulfide for preparation of cyclic dithiocarbonates was carried out in water under catalytic amount of an organic base such as dimethylaminopyridine or triethylamine. The reaction conditions are simple and give high yields of desired products.© 2009 HeteroCorporation
Investigation of complexation behavior of the dithiocarbamates of N 1 ,N n -dicinnamylalkane-1,n-diamines with metals
, Article Journal of Molecular Structure ; Volume 1180 , 2019 , Pages 188-195 ; 00222860 (ISSN) ; Soleymani Movahed, F ; Fathi, M. B ; Daliri, R ; Saidi, M. R ; Sharif University of Technology
Elsevier B.V
2019
Abstract
Synthesis and characterization of metal dithiocarbamate complexes of N 1 ,N 3 -dicinnamylpropane-1,3-diamine, N 1 ,N 4 -dicinnamylbutane-1,4-diamine and N 1 ,N 6 -dicinnamylhexane-1,6-diamine are reported. The ligands are prepared using cinnamaldehyde and primary diamines to provide the corresponding diimines, followed by reduction with NaBH 4 to afford the corresponding secondary diamines. Diamines react with carbon disulfide in basic medium to furnish the corresponding bis(dithiocarbamate) salts, which underwent complexation with metals. The prepared complexes were characterized by IR, 1 H and 13 C NMR, TGA and elemental analyses. Although the dinuclear metal dithiocarbamate macrocyclic...
The effect of structural defects on the electron transport of MoS 2 nanoribbons based on density functional theory
, Article Journal of Theoretical and Applied Physics ; Volume 13, Issue 1 , 2019 , Pages 55-62 ; 22517227 (ISSN) ; Fathipour, M ; Faez, R ; Darvish, G ; Sharif University of Technology
SpringerOpen
2019
Abstract
Using non-equilibrium Green’s function method and density functional theory, we study the effect of line structural defects on the electron transport of zigzag molybdenum disulfide (MoS 2 ) nanoribbons. Here, the various types of non-stoichiometric line defects greatly affect the electron conductance of MoS 2 nanoribbons. Although such defects would be lead to the electron scattering, they can increase the transmission of charge carriers by creating new channels. In addition, the presence of S bridge defect in the zigzag MoS 2 nanoribbon leads to more the transmission of charge carriers in comparison with the Mo–Mo bond defect. Also, we find that the different atomic orbitals and their...
Phase transition and field effect topological quantum transistor made of monolayer MoS2
, Article Journal of Physics Condensed Matter ; Volume 30, Issue 23 , 2018 , May ; 09538984 (ISSN) ; Simchi, M ; Fardmanesh, M ; Peeters, F. M ; Sharif University of Technology
Institute of Physics Publishing
2018
Abstract
We study topological phase transitions and topological quantum field effect transistor in monolayer molybdenum disulfide (MoS2) using a two-band Hamiltonian model. Without considering the quadratic (q 2) diagonal term in the Hamiltonian, we show that the phase diagram includes quantum anomalous Hall effect, quantum spin Hall effect, and spin quantum anomalous Hall effect regions such that the topological Kirchhoff law is satisfied in the plane. By considering the q 2 diagonal term and including one valley, it is shown that MoS2 has a non-Trivial topology, and the valley Chern number is non-zero for each spin. We show that the wave function is (is not) localized at the edges when the q 2...
A density functional study of strong local magnetism creation on MoS 2 nanoribbon by sulfur vacancy
, Article Nanoscale ; Volume 2, Issue 8 , 2010 , Pages 1429-1435 ; 20403364 (ISSN) ; Manteghian, M ; Sharif University of Technology
2010
Abstract
In this study a low-width MoS2 ribbon has been used for probing the electronic structure and local magnetic moment near vacancies. A theoretical study with the full-potential Density Functional Theory (DFT) approach (Wien2K code) have shown that when the dimension of MoS2 is reduced from 2-D to 1-D the nonmagnetic semi-conductor MoS2 becomes a magnetic conductor. Our study has shown that a vacancy on the S-edge with 50% coverage intensifies the magnetization of the edge of the MoS2 nanoribbon but such a vacancy on S-edge with 100% coverage causes this magnetic property to disappear. It is concluded that in both of them, there are positive or negative strong gradients of local magnetic moment...
Synthesis of poly-substituted thiophenes in the realm of sulfonylketenimines chemistry
, Article Journal of Sulfur Chemistry ; Volume 41, Issue 2 , 2020 , Pages 146-153 ; Sedaghat, A ; Nematpour, M ; Jahani, M ; Tabatabai, S. A ; Sharif University of Technology
Taylor and Francis Ltd
2020
Abstract
An efficient synthesis of highly substituted thiophenes was developed by means of sulfonylketenimines in a multi-step reaction including heterocumulene system containing sulfur and nitro-alkanes with acidic α-hydrogen. The speed and ease of conducting this four-component reaction under mild conditions and using available materials makes it an ideal method to synthesize high purity substituted thiophenes with sulfonamide moiety. All structures synthesized are confirmed by the instrumental analysis (EI-MS, IR and 1H /13C-NMR). © 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group
Supported iron oxide nanoparticles: Recoverable and efficient catalyst for oxidative S-S coupling of thiols to disulfides
, Article Catalysis Communications ; Volume 40 , 2013 , Pages 13-17 ; 15667367 (ISSN) ; Kakeshpour, T ; Saidi, M. R ; Sharif University of Technology
2013
Abstract
Supported iron oxide nanoparticles are found to be efficient and recoverable catalyst in the selective oxidation of thiols to their corresponding disulfides using hydrogen peroxide as green oxidant at room temperature. The protocol features an easy work-up, simplicity and the utilizing mild reaction conditions, as well as high selectivity toward disulfides, are highly advantageous compared to alternative reported methodologies. The supported iron oxide nanoparticles could be easily recovered and reused several times without any loss of activity. ICP-MS results prove that there is no metal leaching observed, and demonstrating the stability of the catalyst under the reaction conditions
A rapid and convenient synthesis of gem-bis(dithiocarbamate) derivatives from primary aliphatic amines, carbon disulfide, and aromatic aldehydes using boron trifluoride-diethyl etherate
, Article Tetrahedron Letters ; Vol. 55, Issue. 25 , 2014 , Pages 3572-3575 ; ISSN: 00404039 ; Ghiyaei, A. G. G ; Notash, B ; Shayegan, M. H ; Amani, V ; Sharif University of Technology
Abstract
An efficient route for the synthesis of gem-bis(dithiocarbamate) derivatives is developed using dithiocarbamic acid salts generated from primary aliphatic amines and CS2. The method offers high yields, employs mild reaction conditions, and demonstrates excellent functional group compatibility. The structures of the products were confirmed spectroscopically and by X-ray analysis
A facile one-pot, four-component synthesis of (Z)-isomer of rhodanine-oxindole derivatives under environmentally benevolent conditions
, Article Synthetic Communications ; Volume 52, Issue 2 , 2022 , Pages 175-184 ; 00397911 (ISSN) ; Aghamiri, B ; Jalalinik, M ; Sharif University of Technology
Taylor and Francis Ltd
2022
Abstract
Herein, an efficient and sustainable one-pot, four-component access to rhodanine-oxindole derivatives is achieved by a reaction between primary amines, carbon disulfide, ethyl chloroacetate, and cyano-substituted alkenyl oxindoles. The reaction was conducted without any harsh conditions as well as exhausting workup in polyethylene glycol (PEG) as a green solvent at room temperature and delivered rhodanine-oxindole products in high yield. This publication is the first easy protocol to be reported for the rapid construction of new rhodanine-oxindole derivatives at room temperature without harsh conditions and via multicomponent reaction. © 2021 Taylor & Francis Group, LLC
In situ forming interpenetrating hydrogels of hyaluronic acid hybridized with iron oxide nanoparticles
, Article Biomaterials Science ; Volume 3, Issue 11 , Aug , 2015 , Pages 1466-1474 ; 20474830 (ISSN) ; Shi, L ; Bagheri, R ; Kabiri, K ; Hilborn, J ; Ossipov, D. A ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
Four derivatives of hyaluronic acid (HA) bearing thiol (HA-SH), hydrazide (HA-hy), 2-dithiopyridyl (HA-SSPy), and aldehyde groups (HA-al) respectively were synthesized. Thiol and 2-dithiopyridyl as well as hydrazide and aldehyde make up two chemically orthogonal pairs of chemo-selective functionalities that allow in situ formation of interpenetrating (IPN) disulfide and hydrazone networks simultaneously upon the mixing of the above derivatives at once. The formation of IPN was demonstrated by comparing it with the formulations of the same total HA concentration but lacking one of the reactive components. The hydrogel composed of all four components was characterized by a larger elastic...
Ballistic molecular transport through two-dimensional channels
, Article Nature ; Volume 558 , 20 June , 2018 , Pages 420-423 ; 00280836 (ISSN) ; Geim, A. K ; Janardanan, A ; Rooney, A. P ; Esfandiar, A ; Hu, S ; Dar, S. A ; Grigorieva, I. V ; Haigh, S. J ; Wang, F. C ; Radha, B ; Sharif University of Technology
Nature Publishing Group
2018
Abstract
Gas permeation through nanoscale pores is ubiquitous in nature and has an important role in many technologies 1,2 . Because the pore size is typically smaller than the mean free path of gas molecules, the flow of the gas molecules is conventionally described by Knudsen theory, which assumes diffuse reflection (random-angle scattering) at confining walls 3-7 . This assumption holds surprisingly well in experiments, with only a few cases of partially specular (mirror-like) reflection known 5,8-11 . Here we report gas transport through ångström-scale channels with atomically flat walls 12,13 and show that surface scattering can be either diffuse or specular, depending on the fine details of the...
N-Chlorosuccinimide: A simple and efficient reagent for the preparation of symmetrical disulfides
, Article Journal of Sulfur Chemistry ; Volume 27, Issue 2 , 2006 , Pages 165-167 ; 17415993 (ISSN) ; Ghafuri, H ; Karimi Jaberi, Z ; Sharif University of Technology
2006
Abstract
The efficient oxidative coupling of thiols to disulfides with N-chlorosuccinimide (NCS) at room temperature is described. Simple workup, economical method, high yields of products are some advantages of this method. © 2006 Taylor & Francis
Sodium hypochlorite/montmorillonite K10: An effective oxidant for the oxidation of thiols to disulfides
, Article Letters in Organic Chemistry ; Volume 2, Issue 5 , 2005 , Pages 485-486 ; 15701786 (ISSN) ; Rahimi, A ; Karimi Jaberi, Z ; Sharif University of Technology
2005
Abstract
Sodium hypochlorite adsorbed on montmorillonite K10 is a useful oxidant for the oxidation of thiols to disulfides under the room temperature. © 2005 Bentham Science Publishers Ltd