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Transition metal-free addition of dithiocarbamates to alkynes: One-pot regioselective synthesis of S-vinyl dithiocarbamates under solvent-free conditions
, Article Monatshefte fur Chemie ; Vol. 145, issue. 3 , 2014 , pp. 521-526 ; ISSN: 00269247 ; Saidi, M. R ; Sharif University of Technology
Abstract
A convenient, green, and efficient procedure for the synthesis of S-vinyl dithiocarbamates by a simple one-pot three-component condensation of an amine, carbon disulfide, and alkynes is described in the absence of any transition metal catalyst and under solvent-free conditions. This clean and improved method selectively furnishes the corresponding (Z)-S-vinyl dithiocarbamates in good to excellent yields. The reaction is clean with simple product workup and is carried out at 80 C. Graphical Abstract: [Figure not available: see fulltext.]
Waste-Free thiolysis of epoxide in water with high yield
, Article Journal of the Iranian Chemical Society ; Volume 6, Issue 1 , 2009 , Pages 165-167 ; 1735207X (ISSN) ; Akbari, E ; Saidi, M. R ; Sharif University of Technology
Iranian Chemical Society
2009
Abstract
An environmentally benign and efficient process for the preparation of β-hydroxysulfides was developed by a practical and simple reaction of thiols with epoxides in water catalyzed by K2CO3 in high yields and short reaction times
Utility of N-bromosuccinimide-water combination as a green reagent for synthesis of N,S-heterocycles and dithiocarbamates from styrenes
, Article Synlett ; Volume 31, Issue 18 , August , 2020 , Pages 1823-1827 ; Goudarzi, M ; Sharif University of Technology
Georg Thieme Verlag
2020
Abstract
An efficient and unprecedented green protocol has been developed for the synthesis of N,S-heterocycles from styrenes and alkyl dithiocarbamates with high to excellent yields. The reaction of primary or secondary amines, CS 2, and styrenes was carried out in water in the presence of a catalytic amount of an inorganic base. All products were made by using an N -bromosuccinimide-H 2O combination as a green and inexpensive reagent. © 2020 American Institute of Physics Inc.. All rights reserved
Green carbon-based nanocomposite biomaterials through the lens of microscopes
, Article Emergent Materials ; 2021 ; 25225731 (ISSN) ; Ahmadi, S ; Rabiee, M ; Bagherzadeh, M ; Vahabi, H ; Jouyandeh, M ; Saeb, M. R ; Sharif University of Technology
Springer Nature
2021
Abstract
In this work, a green synthesis method was designed and practiced to develop bioactive and biocompatible carbon-based nanocomposites biomaterials. ZnO nanoparticles were synthesized in assistance of leaf extracts and added to a composite nanostructure composed of the reduced graphene oxide (rGO) and multi-walled carbon nanotubes (MWCNT). The resulting green nanocomposite revealed ability to make π-π interactions, hydrogen bonding, and van der Waals interactions with the doxorubicin (DOX). Then, the surface morphology of the synthesized nanocomposite was investigated, and the interrelationship between the surface morphology, relative cell viability, and drug uptake and release behavior were...
Colloidal gold nanoparticles: an unexpected catalytic activity in aqueous phase with dioxygen
, Article catalysis letters ; Volume 144, Issue 7 , July , 2014 , pp. 1219-1222 ; 1572-879X ; Robatjazi, H. (Hossein) ; Hormozi-Nezhad, M. (Mohammad Reza) ; Padervand, M. (Mohsen) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
Abstract
Selective oxidations of alkenes were investigated using molecular oxygen in aqueous solution under mild conditions. Colloidal gold nanoparticles are particularly versatile catalysts for oxidation reaction with exceptionally high efficiency and significant selectivity. Gold nanorods (Au NRs) exhibited a slightly enhanced activity compare to gold nanospheres
A sustainable approach to the Ugi reaction in deep eutectic solvent
, Article Comptes Rendus Chimie ; Volume 16, Issue 12 , 2013 , Pages 1098-1102 ; 16310748 (ISSN) ; Dezfooli, S ; Hashemi, M. M ; Sharif University of Technology
2013
Abstract
The Ugi reaction goes fast with high yields in a recyclable and biodegradable low-melting mixture of choline chloride and urea (DES) as a novel and efficient reaction medium. The DES is applicable to a wide range of aldehydes, amines, isocyanides, and acids in good to excellent isolated yields (60-92%) and short reaction times (2-5 h) and can be reused four times without any loss of activity
A non-cyanide route for glutaric acid synthesis from oxidation of cyclopentene in the ionic liquid media
, Article Process Safety and Environmental Protection ; Volume 100 , 2016 , Pages 203-207 ; 09575820 (ISSN) ; Hashemi, M. M ; Sharif University of Technology
Institution of Chemical Engineers
Abstract
The current work deals with the catalytic application of bis(1-butyl-3-methylimidazolium) tungstate ([BMIm]2WO4) for green synthesize of glutaric acid (GA) through oxidative cleavage of cyclopentene. In this method, 30% hydrogen peroxide (H2O2) was used as oxidant with water as the sole by-product of the reaction. Compared to the current synthetic procedures, this protocol is significantly improved in the environmental point of view. Moreover, the effect of the various parameters was investigated on the reaction efficiency. It was found that high yield of GA could obtain without using special methodologies or precautions. The catalytic system is reusable for several times
Investigation of Dithiocarabamates Reaction with α,β-Unsaturated Aldehydes
, M.Sc. Thesis Sharif University of Technology ; Mahmoudi Hashemi, Mohammad (Supervisor) ; Ziyaei Halimehjani, Azim (Supervisor)
Abstract
Dithiocarbamates are a group of compounds that nowadays have been used extensively in pharmaceutical agents, organicsynthesis and as fungicides in agriculture.We haveshown, an efficient. regiospecific method for the synthesis of cyclic dithiocarbamates by one-pot three-component cascade reaction of an amine, CS2 and α,β-unsaturated aldehyde via Michael addition/hemiamination reaction in watre under a mild and green procedure with excellent yields and complete regioselectivity
Synthesis of Dithiocarbamate by Markonikov Addition Reaction
, M.Sc. Thesis Sharif University of Technology ; Mahmoodi Hashemi, Mohammad (Supervisor) ; Ziyaei Halimehjani, Azim (Supervisor)
Abstract
Development of strategically important processes which are environmentally benign with simple methodology and work-up by low toxic material is currently reciving considerable attention.In recent years, dithiocarbamates (DTCs) and their synthesis with a green procedure have received many attention because of their undeniable applications.These synthetic compounds play important roles either in academia and industry. Here a simple, efficient and regiospecific method for synthesis of dithiocarbamates is described by one-pot three-component reaction of an amine, CS2 and alkyl vinyl ether via Markovnikov addition reaction in poly ethylene glycol (PEG) under a mild and green procedure with...
Evaluation of prepared natural polymers in the extraction of chlorobenzenes from environmental samples: sol–gel–based cellulose acetate-phenyltriethoxysilane fibers
, Article Microchemical Journal ; Volume 142 , 2018 , Pages 265-272 ; 0026265X (ISSN) ; Golzari Aqda, T ; Enteshari Najafabadi, M ; Sharif University of Technology
Abstract
In this research, three fibers including cellulose acetate (CA), CA–phenyltriethoxysilane (PTES) prepared via sol–gel electrospinning and sol–gel–based CA fibers immersed in PTES solution (dipped–CA–PTES) were prepared. The composition and morphology of the prepared fibers were evaluated by energy dispersive X-ray spectroscopy and field emission scanning electron microscopy. The prepared fibers were implemented in a home–made needle trap device, followed by thermal desorption of the selected chlorobenzenes (CBs) to a gas chromatography–flame ionization detector. Finally, parameters affecting the extraction methodology such as the amount of sorbent, extraction time and temperature, desorption...
Cobalt-copper ferrite nanoparticles catalyzed click reaction at room-temperature: green access to 1,2,3-triazole derivatives
, Article ChemistrySelect ; Volume 3, Issue 9 , 2018 , Pages 2586-2593 ; 23656549 (ISSN) ; Pourkaveh, R ; Ahangarpour, M ; Sharif University of Technology
Wiley-Blackwell
2018
Abstract
A typical Cobalt-Copper ferrite nanoparticles (CoCuFe2O4) was used as a catalyst for one-pot [3+2] cycloaddition of alkyl azides with alkynes at room temperature in green media. These nanoparticles were synthesized by using co-precipitation method and were fully characterized by physiochemical technique. By this catalyst system, various types of alkyl halides were coupled with alkynes efficiently to furnish 1,2,3 triazoles in excellent yields within short reaction time. The requirement on energy and time for the Click reaction extremely minimized in this method compared to previously reported reactions as an inevitable trend in development of green chemistry. Using green solvent, inexpensive...
Cysteic acid grafted to magnetic graphene oxide as a promising recoverable solid acid catalyst for the synthesis of diverse 4H-chromene
, Article Scientific Reports ; Volume 10, Issue 1 , December , 2020 ; Eslami, M ; Hoda, G ; Sharif University of Technology
Nature Research
2020
Abstract
4H-chromenes play a significant role in natural and pharmacological products. Despite continuous advances in the synthesis methodology of these compounds, there is still a lack of a green and efficient method. In this study, we have designed cysteic acid chemically attached to magnetic graphene oxide (MNPs·GO-CysA) as an efficient and reusable solid acid catalyst to synthesize 4H-chromene skeletons via a one-pot three components reaction of an enolizable compound, malononitrile, an aldehyde or isatin, and a mixture of water–ethanol as a green solvent. This new heterogeneous catalyst provides desired products with a good to excellent yield, short time, and mild condition. This procedure...
A simple and efficient method for synthesis of isocyanurates catalyzed by potassium phthalimide under solvent-free conditions
, Article Letters in Organic Chemistry ; Volume 2, Issue 8 , 2005 , Pages 734-738 ; 15701786 (ISSN) ; Dekamin, M. G ; Koozehgari, G. R ; Sharif University of Technology
2005
Abstract
The catalytic activity of potassium salts of phthalimide (PPI) and succinimide (PSI), as organonucleophilic catalysts, has been investigated for the cyclotrimerization of isocyanates under solvent-free conditions. PPI showed better catalytic activity in comparison with PSI. Diverse and challenging isocyanates afforded the respective symmetrical isocyanurates in good to quantitative yields in an atom economic reaction without any phase transfer catalyst. © 2005 Bentham Science Publishers Ltd
Efficient deep eutectic solvents catalyzed synthesis of pyran and benzopyran derivatives
, Article Journal of Molecular Liquids ; Volume 186 , 2013 , Pages 76-80 ; 01677322 (ISSN) ; Dezfooli, S ; Khajeh, M ; Hashemi, M. M ; Sharif University of Technology
2013
Abstract
An ecofriendly one-pot multicomponent reaction of 1,3-dicarbonyl compounds, aldehydes, and malononitrile was carried out in a different deep eutectic solvent (DES) based on choline chloride, to synthesize highly functionalized benzopyran and pyran derivatives under catalyst-free conditions. The results showed that urea:choline chloride based DES is the best solvent and is successfully applicable to a wide range of aldehydes, active methylene compounds with high yields (75-95%) and short reaction times (1-4 h)
Design a New Magnetic Nanocatalyst Based on Palladium (II) and Its Application for the Selective Oxidation Reaction of Alcohol to Aldehyde
, M.Sc. Thesis Sharif University of Technology ; Matloubi Moghaddam, Firouz (Supervisor) ; Sajadi, Ali Akbar (Supervisor)
Abstract
In the first chapter of the thesis the synthesis of indolylsulfanyl acetamide derivatives using thio-oxindoles has been reported. The properties of this reaction are, one-pot, without using catalysts, acetonitrile solvent and the raw material is available. This reaction has high yield and seperation products is done using column chromatography. Indole derivatives has various medicinal and biological properties and synthetic products in this project has indole ring, aldehyde and amide functional groups. In the second chapter of the thesis, a new magnetic nanocatalyst has been designed. The magnetic nanoparticles were coated with triazole ligand and then palladium (II) ion was loaded onto the...
Designing of Magnetic Nanocatalyst and their Application in Oxidation of Alcohols and Other Functional Groups
, Ph.D. Dissertation Sharif University of Technology ; Mahmoodi Hashemi, Mohammad (Supervisor)
Abstract
In this thesis, heterogenous catalysts based on magnetic nanoparticles were synthesized. In these catalysts, magnetic nanoparticles were coated with defferent fuctional groups to produce a catalyst with magnetic properties which is easily separated from the reaction medium. The structure of synthesized catalyst was characterized using techniques such as transmission electron microscopy (TEM), scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and CHNS elemental analysis. Easy preparation, low cost, biodegradability and high thermal stability are advantages of these catalysts. At the end, the catalytic properties of resulted catalysts were investigated in many...
The Immobilization of Saccharides onto the Magnetic Nanoparticles of Fe3O4 and its Application as an Efficient Ligand for Support and Stabilization of Metallic Cations in Organic Reactions such as Synthesis of 1, 2, 3-Triazoles & 2-Substituted Benzoxazoles
, M.Sc. Thesis Sharif University of Technology ; Matlubi Moghaddam، Firouz (Supervisor)
Abstract
One of the most challengeable topic in the field of green chemistry is the synthesis of organic structure in water. In this project immobilized glucose on Fe3O4 was prepared as a nano heterogeneous dispersive catalyst in water. The catalyst was fully characterized by FT-IR, TGA, CHN, SEM, EDX and atomic absorption spectroscopy. The synthesized catalyst was used in the synthesis of different derivatives of 1,2,3-triazole via one-pot three component reaction of alkynes, alkyl halides, sodium azides; And to the best of our knowledge this novel catalyst coin sides to the principles of green chemistry. This nano catalyst can be recycled and reused for several runs without significant loss of its...
Green Chemistry of Copper Oxide Nanoparticles from Salvia Hispanica: Potential Biological and Catalyst Activity in Click Chemistry
, M.Sc. Thesis Sharif University of Technology ; Bagherzadeh, Mojtaba (Supervisor)
Abstract
The present work was aimed to account a green and eco-friendly synthesis of copper oxide nanoparticles using Salvia hispanica extracts for the first time.The synthesized copper oxide nanoparticles were fully characterized using FT-IR, XRD, FESEM, EDX, TEM and UV-Vis spectroscopy techniques. The average particle size of copper oxide nanoparticles is around 35 nm and shape of nanoparticles are spherical. Biological activity of the synthesized nanoparticles were evaluated in terms of antibacterial assessments against Staphylococcus aureus and Escherichia coli. In the following, the potential antibacterial activity against gram positive (S.aureus) and gram negative (E.coli) bacteria’s were...
Design, Synthesis and Use of Transition Metal Oxide Spinels (Cobalt and Iron) as Catalysts in Organic Reactions
, M.Sc. Thesis Sharif University of Technology ; Matloubi Moghadam, Firouz (Supervisor)
Abstract
Bread scraps with transition metals oxides spinels have been utilized to synthesize¬ magnetic nanocatalyst. The heterogeneous catalyst was characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), thermogravimetric analysis (TGA) and transmission electron microscopy (TEM). The reaction was performed for tandem Knoevenagel-Micheal reaction in the presence of synthesized nanocatalyst as a heterogeneous, environmentally benign, cost-effective catalyst with high catalytic activity using EtOH as a green solvent. The magnetic nanocatalyst was applied to synthesize tetraketones and pyranopyrazoles...
Dithiocarbamates as an efficient intermediate for the synthesis of 2-(alkylsulfanyl)thiazoles in water
, Article Tetrahedron Letters ; Volume 57, Issue 8 , 2016 , Pages 883-886 ; 00404039 (ISSN) ; Hasani, L ; Ali Alaei, M ; Saidi, M.R ; Sharif University of Technology
Elsevier Ltd
2016
Abstract
A simple, green and high-yielding procedure for the synthesis of 4-substituted-2-(alkylsulfanyl)thiazoles from the reaction of dithiocarbamates and α-halocarbonyl containing compounds in water is described. Also, a one-pot, two-step procedure for the synthesis of 2-(alkylsulfanyl)thiazoles from acetophenone and dithiocarbamates was developed. © 2016 Elsevier Ltd. All rights reserved