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Highly regioselective, base-catalyzed, biginelli-type reaction of aldehyde, phenylacetone and urea/thiourea kinetic vs. thermodynamic control
, Article Journal of Sulfur Chemistry ; Volume 39, Issue 2 , 2018 , Pages 151-163 ; 17415993 (ISSN) ; Rezaee, E ; Jahani, M ; Tabatabai, A ; Sharif University of Technology
Taylor and Francis Ltd
2018
Abstract
An efficient one-pot regioselective synthesis of various novel 3,4-dihydropyrimidin-2(1H)-one (DHPMs) via a three-component Biginelli-type condensation of aldehyde, phenylacetone and urea/thiourea under two different based-catalyzed conditions is described. In kinetic control path, lithium N, N-diisopropylamide (LDA-20 mol % generated in situ from n-BuLi and diisopropylamine) was used as the base, in tetrahydroforane (THF) as the solvent at 0°C. Thermodynamic control path was run with NaH as the base, in EtOH as the solvent under reflux status. The simple procedure, mild base-catalytic reaction conditions, no column chromatography and good to high yields are important features of this...
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
Highly regioselective, base-catalyzed, biginelli-type reaction of aldehyde, phenylacetone and urea/thiourea kinetic vs. thermodynamic control
, Article Journal of Sulfur Chemistry ; 2017 , Pages 1-13 ; 17415993 (ISSN) ; Rezaee, E ; Jahani, M ; Tabatabai, S. A ; Sharif University of Technology
2017
Abstract
An efficient one-pot regioselective synthesis of various novel 3,4-dihydropyrimidin-2(1H)-one (DHPMs) via a three-component Biginelli-type condensation of aldehyde, phenylacetone and urea/thiourea under two different based-catalyzed conditions is described. In kinetic control path, lithium N, N-diisopropylamide (LDA-20 mol % generated in situ from n-BuLi and diisopropylamine) was used as the base, in tetrahydroforane (THF) as the solvent at 0°C. Thermodynamic control path was run with NaH as the base, in EtOH as the solvent under reflux status. The simple procedure, mild base-catalytic reaction conditions, no column chromatography and good to high yields are important features of this...
A copper-catalyzed synthesis of functionalized quinazolines from isocyanides and aniline tri- and dichloroacetonitrile adducts through intramolecular C-H activation
, Article Synlett ; Volume 28, Issue 12 , 2017 , Pages 1441-1444 ; 09365214 (ISSN) ; Rezaee, E ; Tabatabai, S. A ; Jahani, M ; Sharif University of Technology
2017
Abstract
A novel class of substituted quinazolines were prepared in good yields by a one-pot three-component reaction of isocyanides with adducts of anilines and tri- or dichloroacetonitrile, followed by intramolecular C-H activation, catalyzed by copper(I) iodide with l -proline as a ligand in acetonitrile at room temperature. © 2017 Georg Thieme Verlag Stuttgart .New York-Synlett
Synthesis of functionalized benzothiadiazine 1,1-dioxide derivatives via intramolecular C–H activation reactions of trichloroacetamidine and benzenesulfonyl chloride
, Article Tetrahedron Letters ; Volume 59, Issue 21 , 23 May , 2018 , Pages 2054-2056 ; 00404039 (ISSN) ; Rezaee, E ; Jahani, M ; Tabatabai, S. A ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
The synthesis of functionalized benzothiadiazine 1,1-dioxide derivatives was achieved through a novel three-component intramolecular C–H activation reaction of trichloroacetonitrile, benzenesulfonyl chloride, and various primary amines. This reaction was performed in the presence of catalytic copper(I) and L-proline as the ligand in tetrahydrofuran at room temperature. © 2018 Elsevier Ltd
Novel one-pot synthesis of functionalized quinolines from isocyanides, aniline, and acetylene dicarboxylate via cu-catalyzed intramolecular C─H activation reactions
, Article Journal of Heterocyclic Chemistry ; Volume 56, Issue 4 , 2019 , Pages 1254-1259 ; 0022152X (ISSN) ; Rezaee, E ; Jahani, M ; Tabatabai, S. A ; Sharif University of Technology
HeteroCorporation
2019
Abstract
The one-pot synthesis of a novel class of substituted quinoline derivatives with good yields is achieved via the Cu-catalyzed intramolecular C─H activation reaction between isocyanides, aniline, and acetylene dicarboxylate in MeCN at room temperature. The existence of one-pot conditions, availability of a starting material-catalyst, the absence of column chromatography, and a high yield of products are among the advantages of this method. The structures are confirmed spectroscopically (1H NMR and 13C NMR, IR, and EI-MS) and through elemental analyses
Ultrasound-assisted synthesis of highly functionalized benzo[1,3]thiazine via Cu-catalyzed intramolecular C–H activation reaction from isocyanides, aniline-benzoyl(acetyl) isothiocyanate adduct
, Article Ultrasonics Sonochemistry ; Volume 50 , 2019 , Pages 1-5 ; 13504177 (ISSN) ; Rezaee, E ; Jahani, M ; Tabatabai, S. A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
A facile sonochemical route for the synthesis of benzo[1,3]thiazine derivatives via a one pot, multicomponent, intramolecular C–H activation reaction from isocyanides, aniline and benzoyl (acetyl) isothiocyanate adduct catalyzed by copper (I) iodide in acetone at 30 °C have been reported. The advantages of the described method include using simple and readily available starting materials and performing under mild copper-catalytic reaction conditions and also obtaining pure product with high yield without applying column chromatography. Furthermore, using the sonochemical methodology as an efficient method led to reduce the reaction times. © 2018 Elsevier B.V
Ultrasound-assisted synthesis of highly functionalized benzo[1,3]thiazine via Cu-catalyzed intramolecular C–H activation reaction from isocyanides, aniline-benzoyl(acetyl) isothiocyanate adduct
, Article Ultrasonics Sonochemistry ; Volume 50 , 2019 , Pages 1-5 ; 13504177 (ISSN) ; Rezaee, E ; Jahani, M ; Tabatabai, S. A ; Sharif University of Technology
Elsevier B.V
2019
Abstract
A facile sonochemical route for the synthesis of benzo[1,3]thiazine derivatives via a one pot, multicomponent, intramolecular C–H activation reaction from isocyanides, aniline and benzoyl (acetyl) isothiocyanate adduct catalyzed by copper (I) iodide in acetone at 30 °C have been reported. The advantages of the described method include using simple and readily available starting materials and performing under mild copper-catalytic reaction conditions and also obtaining pure product with high yield without applying column chromatography. Furthermore, using the sonochemical methodology as an efficient method led to reduce the reaction times. © 2018 Elsevier B.V
Synthesis of highly functionalized quinazoline-2,4(1H,3H)-diones from isocyanides, aniline and isocyanate via Cu-catalyzed intermolecular C-H activation reactions
, Article Letters in Organic Chemistry ; Volume 17, Issue 11 , 2020 , Pages 832-836 ; Fasihi Dastjerdi, H ; Jahani, M ; Tabatabai, S. A ; Sharif University of Technology
Bentham Science Publishers
2020
Abstract
A simple and appropriate procedure for the synthesis of quinazoline-2,4(1H,3H)-dione derivatives from isocyanides, aniline and isocyanate via the Cu-catalyzed intramolecular C-H activation reaction is reported. The advantages of this method are one-pot conditions, accessible starting materials-catalyst, high yield of products, and short reaction times. The structures are confirmed spectroscopically (1H-and13C-NMR, IR and EI-MS) and by elemental analyses. © 2020 Bentham Science Publishers
Solubility of CO2 and H2S in the ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate
, Article Journal of Natural Gas Science and Engineering ; Volume 30 , Volume 30 , 2016 , Pages 583-591 ; 18755100 (ISSN) ; Jalili, A. H ; Ghotbi, C ; Rashtchian, D ; Sharif University of Technology
Elsevier
2016
Abstract
The solubility of carbon dioxide and hydrogen sulfide gases in the ionic liquid 1-ethyl-3-methylimidazolium trifluoromethanesulfonate ([C2mim][OTf]) was measured at temperatures from (303.15-353.15) K and pressures up to about 3.0 MPa. The Henry's law constants were determined from the new experimental data, which in turn were used to derive the change of some thermodynamic functions of dissolution of the gases in that particular ionic liquid. The new experimental data were correlated by a combination of the extended Henry's law and Pitzer's model for the excess Gibbs energy. The average relative percent deviation (ARD%) of correlated molality values from experimental data are within...
Experimental Measurement, Modeling And Simulation Of Carbon Dioxide And Hydrogen Sulfide Absorption And Separation By [Emim][Otf]
, M.Sc. Thesis Sharif University of Technology ; Ghotbi, Siroos (Supervisor) ; Rashtchian, Davood (Co-Advisor) ; Jalili, Amir Hossein (Co-Advisor)
Abstract
Inrecent years,research onionic liquidsarehighly developed. Because ofthe uniqueproperties ofionic liquidssuch asnegligiblevapor pressureandthermalstability for use inlarge areasofmajor industries have been considered.However,ionic liquids because they have lessenvironmental wasteas an alternative to convention alorganic solventssuch asaminesalkanolanarise.Ionic liquid sassolventsfor theremoval ofacid gases such as water and gasare investigated. The solubility of CO2 and H2S in the [Emim] [OTF] (1-ethyl-3-methylimidazolium triflate) in the temperature range 303.15 to 343.15 K and pressures up to 2 MPa has been studied experimentally. In order to capture modeling, the model equations of state...
Probability of missed detection as a criterion for receiver placement in MIMO PCL
, Article IEEE National Radar Conference - Proceedings, 7 May 2012 through 11 May 2012, Atlanta, GA ; 2012 , Pages 0924-0927 ; 10975659 (ISSN) ; 9781467306584 (ISBN) ; Chitgarha, M. M ; Radmard, M ; Nayebi, M. M ; Sharif University of Technology
IEEE
2012
Abstract
Using multiple antennas at the transmit and receive sides of a passive radar brings both the benefits of MIMO radar and passive radar. However one of the obstacles arisen in such configuration is the receive antennas placement in proper positions so that the radar performance is improved. Here we just consider the case of positioning one receiver among multiple illuminators of opportunity. Indeed it is a start for the solution of optimizing the geometry of the multiple receivers in a passive radar
An efficient method for the ring opening of epoxides with aromatic amines by Sb(III) chloride under microwave irradiation
, Article Journal of Chemical Research ; Issue 4 , 2008 , Pages 220-221 ; 03082342 (ISSN) ; Hashemi, M. M ; Mottaghi, M. M ; Foroughi, M. M ; Sharif University of Technology
2008
Abstract
SbCl3 supported on montmorillonite K-10 is an efficient catalyst for the ring opening of epoxides with aromatic amines under solvent-free conditions and microwave irradiation to give the corresponding b-amino alcohols in high yields with high regioselectivity
Resource allocation for uav-enabled integrated sensing and communication (isac) via multi-objective optimization
, Article ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings ; Volume 2023-June , 2023 ; 15206149 (ISSN); 978-172816327-7 (ISBN) ; Naghsh, M. M ; Karbasi, M ; Nayebi, M. M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2023
Abstract
In this paper, we consider an integrated sensing and communication (ISAC) system with wireless power transfer (WPT) where an unmanned aerial vehicle (UAV)-based radar serves a group of energy-limited communication users in addition to its sensing functionality. In this architecture, the radar senses the environment in phase 1 (namely sensing phase) and mean-while, the communications users (nodes) harvest and store the energy from the radar transmit signal. The stored energy is then used for information transmission from the nodes to UAV in phase 2, i.e., uplink phase. Performance of the radar system depends on the transmit signal as well as the receive filter; the energy of the transmit...
MIMO radar signal design to improve the MIMO ambiguity function via maximizing its peak
, Article Signal Processing ; Volume 118 , 2016 , Pages 139-152 ; 01651684 (ISSN) ; Radmard, M ; Nazari Majd, M ; Karbasi, S. M ; Nayebi, M. M ; Sharif University of Technology
Elsevier
2016
Abstract
One of the important obstacles in MIMO (Multiple Input Multiple Output) radars is the issue of designing proper transmit signals. Indeed, the capability of signal design is a significant advantage in MIMO radars, through which, the system can achieve much better performance. Many different aspects of this performance improvement have been considered yet, and the transmit signals have been designed to attain such goal, e.g., getting higher SNR or better detector's performance at the receiver. However, an important tool for evaluating the radar's performance is its ambiguity function. In this paper, we consider the problem of transmit signal design, in order to optimize the ambiguity function...
Detection-localization tradeoff in MIMO radars
, Article Radioengineering ; Volume 26, Issue 2 , 2017 , Pages 581-587 ; 12102512 (ISSN) ; Radmard, M ; Chitgarha, M. M ; Bastani, M. H ; Nayebi, M. M ; Sharif University of Technology
2017
Abstract
Two gains play key roles in recently developed MIMO wireless communication systems: "spatial diversity" gain and "spatial multiplexing" gain. The diversity gain refers to the capability to decrease the error rate of the MIMO channel, while the multiplexing gain implicitly refers to the amount of increase in the capacity of the MIMO channel. It has been shown that there is a fundamental tradeoff between these two types of gains, meaning interplay between increasing reliability (via an increase in the diversity gain) and increasing data rate (via an increase in the multiplexing gain). On the other hand, recently, MIMO radars have attracted much attention for their superior ability to enhance...
Antenna placement and power allocation optimization in MIMO detection
, Article IEEE Transactions on Aerospace and Electronic Systems ; Vol. 50, Issue 2 , April , 2014 , pp. 1468-1478 ; Chitgarha, M. M ; Majd, M. N ; Nayebi, M. M ; Sharif University of Technology
2014
Abstract
It is a well known fact that using multiple antennas at transmit and receive sides improves the detection performance. However, in such multiple-input multiple-output (MIMO) configuration, proper positioning of transmitters and receivers is a big challenge that can have significant influence on the performance of the overall system. In addition, determining the power of each transmitter under a total power constraint is a problem that should be solved in order to enhance the performance and coverage of such a system. In this paper, we design the Neyman-Pearson detector under the Rayleigh scatter model and use it to introduce a criterion for the antenna placement at both transmit and receive...
Ambiguity function of MIMO radar with widely separated antennas
, Article Proceedings International Radar Symposium ; 16 -18 June , 2014 ; ISSN: 21555753 ; Chitgarha, M. M ; Nazari Majd, M ; Nayebi, M. M ; Sharif University of Technology
2014
Abstract
There has been much interest, recently, towards exploiting the Multiple-Input Multiple-Output (MIMO) technique in radar. It is shown that using multiple antennas at transmit and receive sides can improve the performance of the system. However, in order to analyze the system's performance, its ambiguity function, i.e. the ambiguity function of a MIMO radar, is needed to be defined. In this paper, beginning from the information theoretic definitions, we derive such function, specifically for a MIMO radar with widely separated antennas
Choosing the position of the receiver in a MISO passive radar system
, Article European Microwave Week 2012: "Space for Microwaves", EuMW 2012, Conference Proceedings - 9th European Radar Conference, EuRAD 2012 ; 2012 , Pages 318-321 ; 9782874870293 (ISBN) ; Majd, M. N ; Radmard, M ; Nayebi, M. M ; Sharif University of Technology
2012
Abstract
By combining the two ideas of MIMO (Multiple Input Multiple Output) and PCL (Passive Coherent Location) in radar, one can achieve the advantages of both recently developed techniques simultaneously. While using multiple antennas at the receive side provides a spatial diversity of the object to be detected, using multiple illuminators of opportunity, most importantly, makes the radar covert to the interceptors. One obstacle in such MIMO configuration is choosing the positions of the receive antennas. In this paper, after analyzing the Neyman-Pearson detector for the DVB-T based PCL, we introduce the probability of missed detection as a criterion to place the receive antenna. Here, we only...
Adaptive filtering techniques in passive radar
, Article Proceedings International Radar Symposium, Dresden ; Volume 2 , June , 2013 , Pages 1067-1078 ; 21555753 (ISSN) ; 9783954042234 (ISBN) ; Radmard, M ; Majd, M. N ; Nayebi, M. M ; Sharif University of Technology
2013
Abstract
One of the most important obstacles in passive radar applications is removing the direct signal from the target channel. Otherwise, week echoes from the targets in the target channel would be ignored due to the limited dynamic range of the system. One of the most effective techniques in this field is using adaptive filters. In this paper various adaptive filters are introduced and their performances are shown and compared