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Hassan Atashin - One of the best experts on this subject based on the ideXlab platform.
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An iron Schiff base complex loaded mesoporous silica nanoreactor as a catalyst for the synthesis of pyrazine-based heterocycles
Transition Metal Chemistry, 2014Co-Authors: Reihaneh Malakooti, Ghasem Rezanejade Bardajee, Somayyeh Hadizadeh, Hassan Atashin, Hadiseh KhanjariAbstract:An iron Schiff base complex was encapsulated in SBA-15 mesoporous silica to afford a Fe(III)-Schiff base/SBA-15 heterogeneous nanocatalyst for the synthesis of Pyridopyrazine and quinoxaline heterocycles. These reactions proceeded in water with excellent yields. The catalyst was characterized by physico-chemical and spectroscopic methods and found to retain the characteristic channel structures of the SBA-15, allowing good accessibility of the encapsulated metal complex.
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palladium schiff base complex loaded sba 15 as a novel nanocatalyst for the synthesis of 2 3 disubstituted quinoxalines and Pyridopyrazine derivatives
Microporous and Mesoporous Materials, 2013Co-Authors: Ghasem Rezanejade Bardajee, Reihaneh Malakooti, Ibrahim Abtin, Hassan AtashinAbstract:Abstract SBA-15-supported palladium catalyst containing N–O chelating Schiff-base ligand has been prepared by the reaction of SBA-15 and a Pd(II) Schiff-base complex. The Pd(II) Schiff-base complex was prepared by the reaction of salicylaldehyde and (3-aminopropyl)trimethoxysilane in methanol and subsequent complexation with Pd(OAc) 2 . Characterization of the nanocatalyst was carried out with powder X-ray diffraction (XRD), BET nitrogen adsorption–desorption method, transmission electron microscopy (TEM), atomic absorption and IR spectroscopy. XRD, TEM and BET analyses revealed the retention of the textural properties of SBA-15 during the grafting procedure. The entitled catalyst was applied successfully for the synthesis of quinoxaline, [1,2-b]pyrazine, pyrido[2,3-b]pyrazine, and pyrido[3,4-b]pyrazine heterocycles with good to excellent yields in water. A variety of 2,3-disubstituted quinoxalines and related heterocycles were synthesized under green conditions by cyclocondensation of various 1,2-diamines and 1,2-diketones using a catalytic amount of the nanocatalyst.
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covalent anchoring of copper schiff base complex into sba 15 as a heterogeneous catalyst for the synthesis of Pyridopyrazine and quinoxaline derivatives
Catalysis Communications, 2012Co-Authors: Ghasem Rezanejade Bardajee, Reihaneh Malakooti, Fereshteh Jami, Zeinab Parsaei, Hassan AtashinAbstract:Abstract The ordered mesoporous silica SBA-15 was covalently anchored with copper (II) Schiff base complex to afford Cu(II)-Schiff base/SBA-15 catalyst. Powder X-ray diffraction, nitrogen adsorption–desorption analyses and TEM image confirm not only the retaining of support properties after anchoring but also the existence of void space in nanometer scale which result in good catalytic activity in the synthesis of Pyridopyrazine and quinoxaline derivatives.
Ghasem Rezanejade Bardajee - One of the best experts on this subject based on the ideXlab platform.
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efficient solvent free synthesis of Pyridopyrazine and quinoxaline derivatives using copper diamsar complex anchored on sba 15 as a reusable catalyst
Chinese Journal of Catalysis, 2015Co-Authors: Marzieh Mohammadi, Ghasem Rezanejade Bardajee, Nader Noroozi PesyanAbstract:Abstract A catalytic system comprising mesoporous silica functionalized with Cu(II)-DiAmSar was synthesized. This was demonstrated as an efficient heterogeneous catalyst for the synthesis of biologically useful Pyridopyrazine and quinoxaline heterocycles under solvent-free conditions. X-ray diffraction, transmission electron microscopy, N 2 adsorption-desorption, Fourtier transformation infrared spectroscopy, and thermogravimetric analysis were used to characterize the catalyst and investigate the texture of SBA-15 during the grafting process.
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An iron Schiff base complex loaded mesoporous silica nanoreactor as a catalyst for the synthesis of pyrazine-based heterocycles
Transition Metal Chemistry, 2014Co-Authors: Reihaneh Malakooti, Ghasem Rezanejade Bardajee, Somayyeh Hadizadeh, Hassan Atashin, Hadiseh KhanjariAbstract:An iron Schiff base complex was encapsulated in SBA-15 mesoporous silica to afford a Fe(III)-Schiff base/SBA-15 heterogeneous nanocatalyst for the synthesis of Pyridopyrazine and quinoxaline heterocycles. These reactions proceeded in water with excellent yields. The catalyst was characterized by physico-chemical and spectroscopic methods and found to retain the characteristic channel structures of the SBA-15, allowing good accessibility of the encapsulated metal complex.
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ZrOCl2·8H2O in water: An efficient catalyst for rapid one-pot synthesis of Pyridopyrazines, pyrazines and 2,3-disubstituted quinoxalines
Comptes Rendus Chimie, 2013Co-Authors: Ghasem Rezanejade BardajeeAbstract:Abstract Zirconium(IV) oxide chloride was found to be a rapid and efficient catalyst for the synthesis of pyrazines and 2,3-disubstituted quinoxalines in water. A variety of Pyridopyrazine and 2,3-disubstituted quinoxaline derivatives are readily prepared in high yields under green conditions by cyclocondensation of the desired 1,2-diamine and 1,2-diketone using a catalytic amount of zirconium(IV) oxide chloride in water. Less active diamines, such as 2,3- and 3,4-diaminopyridines took part in this protocol to provide the desired products in good to excellent yields.
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palladium schiff base complex loaded sba 15 as a novel nanocatalyst for the synthesis of 2 3 disubstituted quinoxalines and Pyridopyrazine derivatives
Microporous and Mesoporous Materials, 2013Co-Authors: Ghasem Rezanejade Bardajee, Reihaneh Malakooti, Ibrahim Abtin, Hassan AtashinAbstract:Abstract SBA-15-supported palladium catalyst containing N–O chelating Schiff-base ligand has been prepared by the reaction of SBA-15 and a Pd(II) Schiff-base complex. The Pd(II) Schiff-base complex was prepared by the reaction of salicylaldehyde and (3-aminopropyl)trimethoxysilane in methanol and subsequent complexation with Pd(OAc) 2 . Characterization of the nanocatalyst was carried out with powder X-ray diffraction (XRD), BET nitrogen adsorption–desorption method, transmission electron microscopy (TEM), atomic absorption and IR spectroscopy. XRD, TEM and BET analyses revealed the retention of the textural properties of SBA-15 during the grafting procedure. The entitled catalyst was applied successfully for the synthesis of quinoxaline, [1,2-b]pyrazine, pyrido[2,3-b]pyrazine, and pyrido[3,4-b]pyrazine heterocycles with good to excellent yields in water. A variety of 2,3-disubstituted quinoxalines and related heterocycles were synthesized under green conditions by cyclocondensation of various 1,2-diamines and 1,2-diketones using a catalytic amount of the nanocatalyst.
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covalent anchoring of copper schiff base complex into sba 15 as a heterogeneous catalyst for the synthesis of Pyridopyrazine and quinoxaline derivatives
Catalysis Communications, 2012Co-Authors: Ghasem Rezanejade Bardajee, Reihaneh Malakooti, Fereshteh Jami, Zeinab Parsaei, Hassan AtashinAbstract:Abstract The ordered mesoporous silica SBA-15 was covalently anchored with copper (II) Schiff base complex to afford Cu(II)-Schiff base/SBA-15 catalyst. Powder X-ray diffraction, nitrogen adsorption–desorption analyses and TEM image confirm not only the retaining of support properties after anchoring but also the existence of void space in nanometer scale which result in good catalytic activity in the synthesis of Pyridopyrazine and quinoxaline derivatives.
Mats Andersson - One of the best experts on this subject based on the ideXlab platform.
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new quinoxaline and Pyridopyrazine based polymers for solution processable photovoltaics
Solar Energy Materials and Solar Cells, 2012Co-Authors: Renee Kroon, Robert Gehlhaar, Timothy T Steckler, Patrik Henriksson, Christian Muller, Jonas Bergqvist, Afshin Hadipour, Paul Heremans, Mats AnderssonAbstract:The recently published quinoxaline/thiophene-based polymer TQ1 has been modified on its acceptor unit, either altering the acceptor strength by incorporating a Pyridopyrazine, substitution of the acceptor-hydrogens by fluorine, or substitution of the alkoxy side chain by alkyl. The changes in physical, electronic and device properties are discussed. For the polymers incorporating the stronger acceptors a decreased performance is found, where in both cases the current in the devices is compromised. Incorporation of the Pyridopyrazine-based acceptor seems to result in more severe or additional loss mechanisms compared to the polymer that incorporates the fluorine atoms. A similar performing material is obtained when changing the alkoxy side chain in TQ1 to an alkyl, where the solar cell performance is mainly improved on the fill factor. It is demonstrated that the standard TQ1 structure is easily modified in a number of ways, showing the versatility and robustness of the standard TQ1 structure and synthesis.
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photodiodes and solar cells based on the n type polymer poly Pyridopyrazine vinylene as electron acceptor
Synthetic Metals, 2003Co-Authors: Fengling Zhang, Maria Jonforsen, Mats Andersson, Mikael D Johansson, Olle InganasAbstract:The photodiodes and solar cells based on the n-type polymer poly(Pyridopyrazine vinylene) as electron acceptor were discussed. It was found that the external quantum efficiency of these diodes reac ...
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synthesis and characterization of poly quinoxaline vinylene s and poly Pyridopyrazine vinylene s with phenyl substituted side groups
Synthetic Metals, 2002Co-Authors: Maria Jonforsen, Tomas Johansson, Olle Inganas, Lena Spjuth, Mats AnderssonAbstract:Poly(quinoxaline vinylene) and poly(Pyridopyrazine vinylene) with 3(2'-ethylhexyloxy)phenyl side-groups have been synthesized and compared with similar polymers with purely aliphatic side-chains. T ...
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synthesis and characterization of soluble and n dopable poly quinoxaline vinylene s and poly Pyridopyrazine vinylene s with relatively small band gap
Macromolecules, 2002Co-Authors: Maria Jonforsen, Tomas Johansson, Olle Inganas, Mats AnderssonAbstract:Synthesis and characterization of poly(quinoxaline vinylene)s and poly(Pyridopyrazine vinylene)s with linear and branched aliphatic side chains are reported. The electron affinity of the polymers was measured with cyclic voltammetry (CV) and found to be highest for the Pyridopyrazine vinylene polymers. Compared to CN-MEH-PPV, the Pyridopyrazine vinylene polymers were easier to reduce, while the quinoxaline derivatives were harder. UV−vis absorption measurements showed that the polymers have relatively small band gaps.
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photodiodes made from poly Pyridopyrazine vinylene polythiophene blends
Synthetic Metals, 2001Co-Authors: Maria Jonforsen, Tomas Johansson, Olle Inganas, I Ahmad, Jonas Larsson, L S Roman, Mattias Svensson, Mats AnderssonAbstract:A PPV-type polymer with the Pyridopyrazine heterocycle (EHH-PPyPzV) has been synthesised and found to have high electron affinity according to electrochemical measurements. When used as the electron accepting material in single-layer-photodiodes, with a thiophene copolymer (PEOPT-co-PAAPT) as the electron donating material, IPCE (incident photon to current conversion efficiency) up to 1% was measured. Atomic force microscopy was used to analyse the blend morphology in the devices.
Reihaneh Malakooti - One of the best experts on this subject based on the ideXlab platform.
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An iron Schiff base complex loaded mesoporous silica nanoreactor as a catalyst for the synthesis of pyrazine-based heterocycles
Transition Metal Chemistry, 2014Co-Authors: Reihaneh Malakooti, Ghasem Rezanejade Bardajee, Somayyeh Hadizadeh, Hassan Atashin, Hadiseh KhanjariAbstract:An iron Schiff base complex was encapsulated in SBA-15 mesoporous silica to afford a Fe(III)-Schiff base/SBA-15 heterogeneous nanocatalyst for the synthesis of Pyridopyrazine and quinoxaline heterocycles. These reactions proceeded in water with excellent yields. The catalyst was characterized by physico-chemical and spectroscopic methods and found to retain the characteristic channel structures of the SBA-15, allowing good accessibility of the encapsulated metal complex.
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palladium schiff base complex loaded sba 15 as a novel nanocatalyst for the synthesis of 2 3 disubstituted quinoxalines and Pyridopyrazine derivatives
Microporous and Mesoporous Materials, 2013Co-Authors: Ghasem Rezanejade Bardajee, Reihaneh Malakooti, Ibrahim Abtin, Hassan AtashinAbstract:Abstract SBA-15-supported palladium catalyst containing N–O chelating Schiff-base ligand has been prepared by the reaction of SBA-15 and a Pd(II) Schiff-base complex. The Pd(II) Schiff-base complex was prepared by the reaction of salicylaldehyde and (3-aminopropyl)trimethoxysilane in methanol and subsequent complexation with Pd(OAc) 2 . Characterization of the nanocatalyst was carried out with powder X-ray diffraction (XRD), BET nitrogen adsorption–desorption method, transmission electron microscopy (TEM), atomic absorption and IR spectroscopy. XRD, TEM and BET analyses revealed the retention of the textural properties of SBA-15 during the grafting procedure. The entitled catalyst was applied successfully for the synthesis of quinoxaline, [1,2-b]pyrazine, pyrido[2,3-b]pyrazine, and pyrido[3,4-b]pyrazine heterocycles with good to excellent yields in water. A variety of 2,3-disubstituted quinoxalines and related heterocycles were synthesized under green conditions by cyclocondensation of various 1,2-diamines and 1,2-diketones using a catalytic amount of the nanocatalyst.
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covalent anchoring of copper schiff base complex into sba 15 as a heterogeneous catalyst for the synthesis of Pyridopyrazine and quinoxaline derivatives
Catalysis Communications, 2012Co-Authors: Ghasem Rezanejade Bardajee, Reihaneh Malakooti, Fereshteh Jami, Zeinab Parsaei, Hassan AtashinAbstract:Abstract The ordered mesoporous silica SBA-15 was covalently anchored with copper (II) Schiff base complex to afford Cu(II)-Schiff base/SBA-15 catalyst. Powder X-ray diffraction, nitrogen adsorption–desorption analyses and TEM image confirm not only the retaining of support properties after anchoring but also the existence of void space in nanometer scale which result in good catalytic activity in the synthesis of Pyridopyrazine and quinoxaline derivatives.
Maria Jonforsen - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and Characterisation of Conjugated Polymers with High Electron Affinity
2020Co-Authors: Maria JonforsenAbstract:This thesis describes synthesis and characterisation of conjugated polymers with high electron affinities. Polymers of this type are desired, for example, for use in light-emitting devices or as electron accepting material in photodiodes/solar cells. The high electron affinities for the polymers synthesized here were obtained from the incorporation of the nitrogen containing heterocycles pyridine, quinoxaline or Pyridopyrazine. Most of the polymers synthesized were alternating copolymers of one of the mentioned heterocycles with vinylene units, i.e. analogues of poly(phenylene vinylene) (PPV). The highest electron affinity, measured with cyclic voltammetry, was obtained for a poly(Pyridopyrazine vinylene) with phenyl substituted side-groups. The affinities of some of the polymers synthesized here are among the highest reported for conjugated polymers, higher than, for example, soluble cyano substituted PPV. One of the poly(Pyridopyrazine vinylene)s synthesized was tested as the electron accepting material in a number of donor/acceptor solar cells. One of the devices had an efficiency which was amongst the highest reported for solar cells based on two conjugated polymers, 7% (555 nm, 0.21 mW/cm2). However, the efficiency of the device was decreased at higher light intensities, probably due to low charge mobility and poor stability. Furthermore, the photo-oxidation process was investigated for four of the polymers; poly(Pyridopyrazine vinylene)s and poly(quinoxaline vinylene)s with different side-groups, and found to be quite complex. At least three factors can influence the stability towards photo-oxidation for this type of polymers; namely band-gap, the HOMO and LUMO levels of the polymer and whether the polymer contains reactive hydrogens such as benzylic hydrogens.
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photodiodes and solar cells based on the n type polymer poly Pyridopyrazine vinylene as electron acceptor
Synthetic Metals, 2003Co-Authors: Fengling Zhang, Maria Jonforsen, Mats Andersson, Mikael D Johansson, Olle InganasAbstract:The photodiodes and solar cells based on the n-type polymer poly(Pyridopyrazine vinylene) as electron acceptor were discussed. It was found that the external quantum efficiency of these diodes reac ...
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synthesis and characterization of poly quinoxaline vinylene s and poly Pyridopyrazine vinylene s with phenyl substituted side groups
Synthetic Metals, 2002Co-Authors: Maria Jonforsen, Tomas Johansson, Olle Inganas, Lena Spjuth, Mats AnderssonAbstract:Poly(quinoxaline vinylene) and poly(Pyridopyrazine vinylene) with 3(2'-ethylhexyloxy)phenyl side-groups have been synthesized and compared with similar polymers with purely aliphatic side-chains. T ...
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synthesis and characterization of soluble and n dopable poly quinoxaline vinylene s and poly Pyridopyrazine vinylene s with relatively small band gap
Macromolecules, 2002Co-Authors: Maria Jonforsen, Tomas Johansson, Olle Inganas, Mats AnderssonAbstract:Synthesis and characterization of poly(quinoxaline vinylene)s and poly(Pyridopyrazine vinylene)s with linear and branched aliphatic side chains are reported. The electron affinity of the polymers was measured with cyclic voltammetry (CV) and found to be highest for the Pyridopyrazine vinylene polymers. Compared to CN-MEH-PPV, the Pyridopyrazine vinylene polymers were easier to reduce, while the quinoxaline derivatives were harder. UV−vis absorption measurements showed that the polymers have relatively small band gaps.
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photodiodes made from poly Pyridopyrazine vinylene polythiophene blends
Synthetic Metals, 2001Co-Authors: Maria Jonforsen, Tomas Johansson, Olle Inganas, I Ahmad, Jonas Larsson, L S Roman, Mattias Svensson, Mats AnderssonAbstract:A PPV-type polymer with the Pyridopyrazine heterocycle (EHH-PPyPzV) has been synthesised and found to have high electron affinity according to electrochemical measurements. When used as the electron accepting material in single-layer-photodiodes, with a thiophene copolymer (PEOPT-co-PAAPT) as the electron donating material, IPCE (incident photon to current conversion efficiency) up to 1% was measured. Atomic force microscopy was used to analyse the blend morphology in the devices.
