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    An efficient one-pot synthesis of 1-aminophosphonates

    , Article Synthesis (Germany) ; Volume 55, Issue 1 , Volume 55, Issue 1 , 2022 , Pages 121-130 ; 00397881 (ISSN) Kaboudin, B ; Faghih, S ; Alavi, S ; Naimi Jamal, M. R ; Fattahi, A ; Sharif University of Technology
    Georg Thieme Verlag  2022
    Abstract
    1-Aminophosphonates are valuable compounds with wide range of applications in biological and industry. Various reaction conditions and catalysts have been reported for the synthesis of 1-aminophosphonates via three-component (dialkyl phosphite + aldehyde + amine) or two-component reaction (dialkyl phosphite + imine). Here a solvent-free synthesis of 1-aminophosphonates under very mild reaction conditions is reported. The three-component condensation reactions of dialkyl phosphite, carbonyl compound, and an amine gave 1- aminophosphonates in good to excellent yields under solvent- and catalyst-free conditions at ambient temperature. Hydrophosphorylation of imines in the presence of dialkyl... 

    Facile and green one-pot synthesis of fluorophore chromeno[4,3-b]quinolin-6-one derivatives catalyzed by halloysite nanoclay under solvent-free conditions

    , Article ChemistrySelect ; Volume 4, Issue 8 , 2019 , Pages 2301-2306 ; 23656549 (ISSN) Ataee Kachouei, T ; Nasr Esfahani, M ; Baltork, I. M ; Mirkhani, V ; Moghadam, M ; Tangestaninejad, S ; Kia, R ; Sharif University of Technology
    Wiley-Blackwell  2019
    Abstract
    In this study, we demonstrated a straightforward method for the easy access of chromeno[4,3-b]quinolin-6-ones via a one-pot three-component reaction of 4-hydroxycoumarin, aldehydes and aryl amines in the presence of halloysite nanoclay as an eco-friendly, inexpensive and green heterogeneous catalyst under solvent-free conditions. Moreover, symmetric and unsymmetric bis-chromeno[4,3-b]quinolin-6-ones were obtained from dialdehyde or diamines in good yields by this method. To date, this is the first report on the synthesis of symmetric and unsymmetric bis-chromeno[4,3-b]quinolin-6-ones via such a one-pot, multicomponent reaction. Some prepared chromeno[4,3-b]quinolin-6-ones displayed as... 

    A one-pot, three-component regiospecific synthesis of dispiropyrrolidines containing a thiophenone ring via 1,3-dipolar cycloaddition reactions of azomethine ylides

    , Article Tetrahedron Letters ; Volume 54, Issue 20 , May , 2013 , Pages 2520-2524 ; 00404039 (ISSN) Moghaddam, F. M ; Khodabakhshi, M. R ; Ghahremannejad, Z ; Foroushani, B. K ; Ng, S. W ; Sharif University of Technology
    2013
    Abstract
    The synthesis of new dispiropyrrolidines containing a thiophenone ring has been achieved by a one-pot, three-component 1,3-dipolar cycloaddition reaction. Unsaturated thiophenone dipolarophiles were reacted with azomethine ylides, generated in situ from sarcosine and cycloketone derivatives (isatin, ninhydrin, acenaphthoquinone), to produce the corresponding cycloadducts in good yields (70-90%). The cycloaddition reaction was found to be highly regio- and diastereoselective  

    Synthesis of 1,4-disubstituted 1,2,3-triazoles from aromatic α-bromoketones, sodium azide and terminal acetylenes via Cu/Cu(OTf)2-catalyzed click reaction under microwave irradiation

    , Article Zeitschrift fur Naturforschung - Section C Journal of Biosciences ; Volume 68, Issue 4 , Apr , 2013 , Pages 391-396 ; 09395075 (ISSN) Fazeli, A ; Oskooie, H. A ; Beheshtiha, Y. S ; Heravi, M. M ; Matloubi Moghaddam, F ; Koushki Foroushani, B ; Sharif University of Technology
    2013
    Abstract
    Reaction of aromatic α-bromoketones, sodium azide and aromatic or aliphatic terminal acetylenes in the presence of Cu/Cu(OTf)2following the classical method (aqueous acetonitrile at room temperature) and under microwave irradiation (H2O at 85 °C) leads to 1,4-disubstituted 1,2,3-triazoles as the final products after simple filtration  

    Damage assessment of a concrete arch dam through nonlinear incremental dynamic analysis

    , Article Soil Dynamics and Earthquake Engineering ; Volume 44 , January , 2013 , Pages 127-137 ; 02677261 (ISSN) Alembagheri, M ; Ghaemian, M ; Sharif University of Technology
    2013
    Abstract
    Damage assessment of concrete arch dams is carried out through nonlinear Incremental Dynamic Analysis (IDA) of a typical arch dam. In this study the Morrow Point arch dam is subjected to a set of 12 three-component earthquakes each scaled to 12 increasing intensity levels. The dam-foundation interaction effects have been investigated by varying foundation's modulus of elasticity to be equal and half of dam concrete's modulus of elasticity. Damage propagation through the dam body is investigated and various IDA curves are created. The performance and various limit-states of the dam structure are examined based on the obtained results. Simple damage indices are proposed through comparison of... 

    Commercial zinc oxide: a facile, efficient, and eco-friendly catalyst for the one-pot three-component synthesis of multisubstituted 2-aminothiophenes via the Gewald reaction

    , Article Industrial and Engineering Chemistry Research ; Volume 51, Issue 44 , October , 2012 , Pages 14577-14582 ; 08885885 (ISSN) Tayebee, R ; Ahmadi, S. J ; Rezaei Seresht, E ; Javadi, F ; Yasemi, M. A ; Hosseinpour, M ; Maleki, B ; Sharif University of Technology
    2012
    Abstract
    An eco-friendly, simple, and effective protocol is developed for the synthesis of various multisubstituted 2-aminothiophenes. In the presence of a catalytic amount of ZnO (5 mol), ketones or aldehydes, malononitrile and elemental sulfur were converted to the corresponding 2-aminothiophene derivatives in moderate to high yields (27%-70%) under solvent-free conditions at 100 °C. Zinc oxide as an efficient, readily available, and reusable catalyst, showed very good catalytic activity for the synthesis of 2-aminothiophene derivatives. Thus far, little research has been reported on the Gewald reaction under solvent-free conditions; to the best of our knowledge, this is the first time that it has... 

    Viscosity prediction of ternary mixtures containing ILs using multi-layer perceptron artificial neural network

    , Article Fluid Phase Equilibria ; Volume 326 , 2012 , Pages 15-20 ; 03783812 (ISSN) Lashkarblooki, M ; Hezave, A. Z ; Al Ajmi, A. M ; Ayatollahi, S ; Sharif University of Technology
    Elsevier  2012
    Abstract
    Ionic liquids (ILs) have been considered as a good candidate to be replaced by the conventional solvent in recent years due to their potential consumptions and unique properties. In the present study, artificial neural network was used to predict the ternary viscosity of mixtures containing ILs. A collection of 729 experimental data points were gathered from the previously public shed literatures. Different topologies of a multilayer feed forward artificial neural network (MFFANN) were examined and optimum architecture was determined. Ternary viscosity data from the literature for 5 ILs with 547 data points have been used to train the network. In addition, to differentiate dissimilar... 

    CuO nanoparticles: A mild and efficient reusable catalyst for the one-pot synthesis of 4-amino-5-pyrimidinecarbonitriles under aqueous conditions

    , Article Defect and Diffusion Forum ; Volume 326-328 , 2012 , Pages 372-376 ; 10120386 (ISSN) ; 9783037854006 (ISBN) Ahmadi, S. J ; Sadjadi, S ; Hosseinpour, M ; Sharif University of Technology
    2012
    Abstract
    An efficient method for the synthesis of 4-amino-5-pyrimidinecarbonitriles by three-component reaction of malononitrile, aldehydes and N-unsubstituted amidines, under aqueous conditions, using CuO nanoparticles as catalyst is reported. The protocol offers advantages in terms of higher yields, short reaction times, and mild reaction conditions, with reusability of the catalyst  

    The effects of SiO 2 and K 2O on glass forming ability and structure of CaOTiO 2P 2O 5 glass system

    , Article Ceramics International ; Volume 38, Issue 4 , 2012 , Pages 3281-3290 ; 02728842 (ISSN) Ahmadi Mooghari, H. R ; Nemati, A ; Eftekhari Yekta, B ; Hamnabard, Z ; Sharif University of Technology
    2012
    Abstract
    The effects of SiO 2 and K 2O were investigated on the glass forming ability (GFA) and structural characteristics of CaOTiO 2P 2O 5 system. Differential thermal analyzer (DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM), FT-IR and 31P magic angle spinning NMR methods were applied for characterizations of the system. Unwanted crystallization in the initial three components base glass composition was observed by adding SiO 2 and crystalline phases such as TiP 2O 7, rutile (TiO 2) and cristobalite (SiO 2) were formed in it. The results showed that K 2O prevents crystallization of glasses and promotes the formation of glass. FT-IR and X-ray diffraction showed that the addition... 

    Three-dimensional nonlinear seismic analysis of concrete faced rockfill dams subjected to scattered P, SV, and SH waves considering the dam-foundation interaction effects

    , Article Soil Dynamics and Earthquake Engineering ; Volume 31, Issue 5-6 , 2011 , Pages 792-804 ; 02677261 (ISSN) Seiphoori, A ; Mohsen Haeri, S ; Karimi, M ; Sharif University of Technology
    2011
    Abstract
    In this study, the nonlinear seismic analysis of a typical three-dimensional concrete faced rockfill dam is reported. Three components of the Loma Prieta (Gilroy 1 station) earthquake acceleration time history are used as input excitation. The dam under study is considered as if it were located in a prismatic canyon with a trapezoidal cross-section. A nonlinear model for the rockfill material is used, and contact elements with Coulomb friction law are utilized at the slab-rockfill interface. Vertical joints in the face slab are also considered in the finite element model. A substructure method, in which the unbounded soil is modelled by the scaled boundary finite element method (SBFEM), is... 

    Investigation of the interphase effects on the mechanical behavior of carbon nanotube polymer composites by multiscale modeling

    , Article Journal of Applied Polymer Science ; Volume 117, Issue 1 , March , 2010 , Pages 361-367 ; 00218995 (ISSN) Montazeri, A ; Naghdabadi, R ; Sharif University of Technology
    2010
    Abstract
    In this article, a multiscale modeling procedure is implemented to study the effect of interphase on the Young's modulus of CNT/polymer composites. For this purpose, a three-phase RVE is introduced which consists of three components, i.e., a carbon nanotube, an interphase layer, and an outer polymer matrix. The nanotube is modeled at the atomistic scale using molecular structural mechanics. Moreover, three-dimensional elements are employed to model the interphase layer and polymer matrix. The nanotube and polymer matrix are assumed to be bonded by van der Waals interactions based on the Lennard-Jones potential at the interface. Using this Molecular Structural Mechanics/Finite Element... 

    Experimental study of three-dimensional flow field around a complex bridge pier

    , Article Journal of Engineering Mechanics ; Volume 136, Issue 2 , 2010 , Pages 143-154 ; 07339399 (ISSN) Beheshti, A. A ; Ataie Ashtiani, B ; Sharif University of Technology
    2010
    Abstract
    In this paper, three-dimensional turbulent flow field around a complex bridge pier placed on a rough fixed bed is experimentally investigated. The complex pier foundation consists of a column, a pile cap, and a 2×4 pile group. All of the elements are exposed to the approaching flow. An acoustic-Doppler velocimeter was used to measure instantaneously the three components of the velocities at different horizontal and vertical planes. Profiles and contours of time-averaged velocity components, turbulent intensity components, turbulent kinetic energy, and Reynolds stresses, as well as velocity vectors are presented and discussed at different vertical and horizontal planes. The approaching... 

    Highly efficient one-pot three-component mannich reaction under solvent-free conditions

    , Article Scientia Iranica ; Volume 16, Issue 2 C , 2009 , Pages 94-98 ; 10263098 (ISSN) Azizi, N ; Ebrahimi, F ; Saidi, M. R ; Sharif University of Technology
    2009
    Abstract
    A mild and practically-convenient one-pot procedure for the direct Mannich reaction has been developed using a condensation of amines, aldehydes and unmodified ketones under solvent free conditions in the presence of Znl 2 with good to excellent yields. The present methodology offers several advantages, such as excellent yields, simple procedures, short reaction times and milder conditions with very small amounts of catalyst. Furthermore, it is the first time that the catalytic activity of several catalysts under solvent free conditions has been studied. It was found that both the diastereoselectivity and the rate of reaction were improved with various Lewis acids and metal oxides. However,... 

    Estimating the seismological source parameters of the 2006 Silakhor earthquake, Iran, using a Genetic Algorithm

    , Article 9th International Conference on Computational Structures Technology, CST 2008, Athens, 2 September 2008 through 5 September 2008 ; Volume 88 , 2008 ; 17593433 (ISSN); 9781905088232 (ISBN) Nicknam, A ; Abbasnia, R ; Eslamian, Y ; Bozorgnasab, M ; Nicknam, A ; Sharif University of Technology
    Civil-Comp Press  2008
    Abstract
    The main objective of this article is to estimate the seismological source parameters of Silakhor earthquake which happened on March 31, 2006, in the southern part of Iran. The Empirical Green's Function approach was used for simulating the main shock and the well known Genetic Algorithm was utilized for modifying the seismological source parameters. The Kostrov slip function was adopted in the model due to its ability in more accurately modeling the rupture process. The selected station was sufficiently far away from the causative source so that the near source problems would not effect on the simulated time series. The GA process compares the elastic response spectra with 5% damping ratio,... 

    Lithium perchlorate mediated three-component preparation of α-aminonitriles under solvent-free conditions

    , Article Synthetic Communications ; Volume 34, Issue 7 , 2004 , Pages 1207-1214 ; 00397911 (ISSN) Azizi, N ; Saidi, M. R ; Sharif University of Technology
    2004
    Abstract
    A three-component reaction between aliphatic or aromatic aldehyde, an amine and trimethylsilyl cyanide mediated by solid LiClO4, gave amino nitriles in good to excellent yields. The reaction proceeded smoothly under solvent-free conditions without any side products  

    Investigating the Application of Self-determination Theory in Increasing the Organizational Commitment of Knowledge-based Employees

    , M.Sc. Thesis Sharif University of Technology Asl Sariraei, Samira (Author) ; Alavi, Babak (Supervisor) ; Aslani, Shirin (Co-Supervisor)
    Abstract
    Researchers recently have focused on integrating motivation and commitment models and presenting common models. This research, for the first time, presents an integrated model of motivation (Self-Determination Theory) and commitment (Three Component Model of Meyer and Allen), from a person-centered view. This study was carried out using two-step cluster analysis method including hierarchical method and optimization of the profiles distance on 306 knowledge workers of four Iranian organizations. The results reveal four profiles, named, based on their characteristics, "people with diverse and mild motives", "motivated individuals with mild intrinsic motives", "motivated people with mild... 

    New pyridinium-based ionic liquid as an excellent solvent-catalyst system for the one-pot three-component synthesis of 2,3-disubstituted quinolines

    , Article ACS Combinatorial Science ; Vol. 16, Issue. 3 , 2014 , Pages 93-100 ; ISSN: 21568952 Anvar, S ; Mohammadpoor-Baltork, I ; Tangestaninejad, S ; Moghadam, M ; Mirkhani, V ; Khosropour, A. R ; Landarani Isfahani, A ; Kia, R ; Sharif University of Technology
    Abstract
    The synthesis of a variety of 2,3-disubstituted quinolines has been achieved successfully via a one-pot three-component reaction of arylamines, arylaldehydes and aliphatic aldehydes in the presence of butylpyridinium tetrachloroindate(III), [bpy][InCl4], ionic liquid as a green catalyst and solvent. Mild conditions with excellent conversions, and simple product isolation procedure are noteworthy advantages of this method. The recyclability of the ionic liquid makes this protocol environmentally benign  

    Copper immobilized onto a triazole functionalized magnetic nanoparticle: A robust magnetically recoverable catalyst for "click" reactions

    , Article RSC Advances ; Volume 5, Issue 5 , 2015 , Pages 3894-3902 ; 20462069 (ISSN) Matloubi Moghaddam, F ; Ayati, S. E ; Sharif University of Technology
    Abstract
    A novel magnetic heterogeneous copper catalyst was synthesized by immobilization of copper ions onto triazole functionalized Fe3O4. The catalyst was fully characterized by FT-IR, TGA, CHN, SEM, TEM, EDX and atomic adsorption spectroscopy. The resulting catalyst was used in the synthesis of 1,2,3-triazoles via a one-pot three component reaction of alkynes, alkyl halides, sodium azides under green conditions. The catalyst was reused ten times and no significant loss of activity was observed  

    The effects of annealing phenomena on the energy absorption of roll-bonded Al-steel sheets during wedge tearing

    , Article Materials Science and Engineering A ; Volume 527, Issue 27-28 , 2010 , Pages 7329-7333 ; 09215093 (ISSN) Beygi, R ; Kazeminezhad, M ; Sharif University of Technology
    Abstract
    The purpose of this paper is to investigate the effects of annealing phenomena on the energy absorption of Al-steel bilayer sheets, bonded by cold rolling, through wedge tearing. Tearing by wedge is a dissipating energy system that includes three components: cutting, friction and plastic deformation due to bending. In order to find the bonding and annealing effects on energy absorption, the non-bonded bilayer sheets are prepared in the same condition of bonded ones. The results show that energy absorption of bonded sheets is larger than that of non-bonded ones. This is due to different plastic bending moment of bonded and non-bonded bilayer sheets. Whenever the bond is improved by heat... 

    Immobilized copper(II) on nitrogen-rich polymer-entrapped Fe3O4 nanoparticles: A highly loaded and magnetically recoverable catalyst for aqueous click chemistry

    , Article Applied Organometallic Chemistry ; Volume 30, Issue 2 , 2016 , Pages 73-80 ; 02682605 (ISSN) Zohreh, N ; Hosseini, S. H ; Pour Javadi, A ; Bennett, C ; Sharif University of Technology
    John Wiley and Sons Ltd 
    Abstract
    A heterogeneous magnetic copper catalyst was prepared via anchoring of copper sulfate onto multi-layered poly(2-dimethylaminoethyl acrylamide)-coated magnetic nanoparticles and was characterized using various techniques. The catalyst was found to be active, effective and selective for one-pot three-component reaction of alkyl halide, sodium azide and alkyne, known as copper-catalyzed click synthesis of 1,2,3-triazoles. As little as 0.3 mol% of catalyst was found to be effective under the optimum conditions. The catalyst could also be recycled and reused up to seven times without significant loss of activity. Thermal stability, high loading level of copper on catalyst, broad diversity of...