20 results on '"Zissimou, Georgia A. [0000-0003-4821-9469]"'
Search Results
2. 4H-1,2,6-Thiadiazine-containing donor–acceptor conjugated polymers: synthesis, optoelectronic characterization and their use in organic solar cells
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Chochos, Christos L., Kalogirou, Andreas S., Ye, Tengling, Tatsi, Elisavet, Katsouras, Athanasios, Zissimou, Georgia A., Gregoriou, Vasilis G., Avgeropoulos, Apostolos, Koutentis, Panayiotis A., Zissimou, Georgia A. [0000-0003-4821-9469], Kalogirou, Andreas S. [0000-0002-5476-5805], Chochos, Christos L. [0000-0002-7783-157X], and Koutentis, Panayiotis A. [0000-0002-4652-7567]
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chemistry.chemical_classification ,Fullerene ,Materials science ,Organic solar cell ,business.industry ,02 engineering and technology ,General Chemistry ,Polymer ,Conjugated system ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Acceptor ,Polymer solar cell ,0104 chemical sciences ,chemistry ,Materials Chemistry ,Optoelectronics ,0210 nano-technology ,business ,Short circuit ,HOMO/LUMO - Abstract
π-Conjugated donor–acceptor (D–A) polymers containing electron withdrawing non-S-oxidized 4H-1,2,6-thiadiazines and electron donating (het)aryl-substituted indacenodithiophenes (IDTs) were prepared and used in organic solar cell (OSC) devices with [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM) as the fullerene acceptor. The non-S-oxidized 4H-1,2,6-thiadiazine containing polymers were wide bandgap absorbers (Eoptg 1.80–1.95 eV) with low-lying highest occupied molecular orbital energy levels (EHOMO −5.5 to −6.1 eV) affording high open circuit voltages (Vocs 0.82–0.96 V) for polymer:fullerene bulk heterojunction (BHJ) OSCs. Owing to enhanced short circuit currents (Jscs) and fill factors (FFs), the 1,2,6-thiadiazin-4(H)-one-based polymers had significantly higher performances (up to 3.83%) vs. the N-(perfluorophenyl)-1,2,6-thiadiazin-4(H)-imine based-polymers (up to 1.37%). 6 14 3658 3667
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- 2018
3. Oxidation of Tetraphenylhexaazaanthracene: Accessing a Scissor Dimer of a 16π Biscyanine
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Zissimou, Georgia A., Constantinides, Christos P., Manoli, Maria, Pieridou, Galatia K., Hayes, Sophia C., Koutentis, Panayiotis Andreas, Hayes, Sophia C. [0000-0002-2809-6193], Koutentis, Panayiotis Andreas [0000-0002-4652-7567], Constantinides, Christos P. [0000-0001-6364-1102], and Zissimou, Georgia A. [0000-0003-4821-9469]
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010405 organic chemistry ,Dimer ,Organic Chemistry ,chemistry.chemical_element ,Manganese ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Biochemistry ,Fluorescence ,0104 chemical sciences ,Singlet ground state ,chemistry.chemical_compound ,Dipole ,chemistry ,Density functional theory ,Physical and Theoretical Chemistry ,Acene ,Single crystal - Abstract
Tetraphenylhexaazaanthracene (TPHA), a fluorescent zwitterionic biscyanine with a closed-shell singlet ground state, on treatment with manganese dioxide or phenyliodine bis(trifluoroacetate) (PIFA), undergoes oxidative dimerization to give a near-zero dipole scissor 5,5′-dimer DI-TPHA. Both acene components of the new dimer DI-TPHA maintain their biscyanine closed-shell singlet ground state motifs, as judged by analysis of both single crystal X-ray crystallographic and density functional theory computational studies however, unlike TPHA, DI-TPHA is only very weakly fluorescent. © 2016 American Chemical Society. 18 5 1116 1119
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- 2016
4. Redox Active Quinoidal 1,2,4-Benzotriazines
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Zissimou, Georgia A., Kourtellaris, Andreas, Manoli, Maria, Koutentis, Panayiotis A., Zissimou, Georgia A. [0000-0003-4821-9469], and Koutentis, Panayiotis A. [0000-0002-4652-7567]
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Trifluoromethyl ,010405 organic chemistry ,Organic Chemistry ,010402 general chemistry ,Ring (chemistry) ,01 natural sciences ,Medicinal chemistry ,Redox ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Yield (chemistry) ,Redox active ,Cyclic voltammetry ,Absorption (chemistry) - Abstract
Modifying the para-quinonimine 1,3-diphenyl-1,2,4-benzotriazin-7(1H)-one (2a) (E1/2–1/0 −1.20 V), by replacing the N1-phenyl by pentafluorophenyl, the C3-phenyl by trifluoromethyl, or the C7 carbonyl by ylidenemalononitrile, led to improved electron affinities as determined by cyclic voltammetry and computational studies. Combining structural changes further improved electron accepting abilities: the most electron deficient analogues (E1/2–1/0 ∼ −0.65 V) involved combining the ylidenemalononitrile groups at C7 with the trifluoromethyl groups at C3. 1,2,5-Thiadiazolo fusion at C5–C6 did not affect the redox behavior but did enhance the UV–vis absorption profile. During the synthesis of the thiadiazolo analogues, 1,4-thiazino-fused analogues 6 were obtained in low yield, which thermally ring contract to the triazafluoranthenones 7. Compounds are fully characterized, and X-ray data are provided for selected analogues. 83 16 9391 9402
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- 2018
5. Anti-cancer activity of phenyl and pyrid-2-yl 1,3-substituted benzo[1,2,4]triazin-7-ones and stable free radical precursors
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Keane, Lee-Ann J., Mirallai, Styliana I., Sweeney, Martin, Carty, Michael P., Zissimou, Georgia A., Berezin, Andrey A., Koutentis, Panayiotis A., Aldabbagh, Fawaz, Zissimou, Georgia A. [0000-0003-4821-9469], Mirallai, Styliana I. [0000-0002-8195-8741], and Koutentis, Panayiotis A. [0000-0002-4652-7567]
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0301 basic medicine ,Pharmaceutical Science ,01 natural sciences ,Medicinal chemistry ,Analytical Chemistry ,anti-tumour ,blatter-type radical ,heterocyclic compound ,NCI ,pleurotin ,TEMPO ,Drug Discovery ,Benzene Derivatives ,Cytotoxicity ,chemistry.chemical_classification ,Triazines ,Orders of magnitude (mass) ,tempo ,Chemistry (miscellaneous) ,MCF-7 Cells ,Molecular Medicine ,HT29 Cells ,Free Radicals ,Cell Survival ,assays ,Radical ,growth ,Antineoplastic Agents ,Heterocyclic Compounds, 4 or More Rings ,Article ,nci ,lcsh:QD241-441 ,Structure-Activity Relationship ,03 medical and health sciences ,lcsh:Organic chemistry ,Cell Line, Tumor ,medicine ,Humans ,Structure–activity relationship ,MTT assay ,Viability assay ,Physical and Theoretical Chemistry ,Dose-Response Relationship, Drug ,010405 organic chemistry ,Organic Chemistry ,Cancer ,toxicity ,medicine.disease ,0104 chemical sciences ,030104 developmental biology ,chemistry ,Heterocyclic compound ,derivatives ,cells - Abstract
Cell viability studies for benzo[1,2,4]triazin-7-ones and 1,2,4-benzotriazinyl (Blatter-type) radical precursors are described with comparisons made with 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO). All of the stable free radicals were several orders of magnitude less cytotoxic than the benzo[1,2,4]triazin-7-ones. The synthesis and evaluation of two new pyrid-2-yl benzo[1,2,4]triazin-7-ones are described, where altering the 1,3-substitution from phenyl to pyrid-2-yl increased cytotoxicity against most cancer cell lines, as indicated using National Cancer Institute (NCI) one-dose testing. COMPARE analysis of five-dose testing data from the NCI showed very strong correlations to the naturally occurring anti-cancer compound pleurotin. COMPARE is program, which analyzes similarities in cytotoxicity data of compounds, and enables quantitative expression as Pearson correlation coefficients. Compounds were also evaluated using the independent MTT assay, which was compared with SRB assay data generated at the NCI. 23 3
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- 2018
6. Synthesis and Characterization of Isodiphenylfluorindone and Isodiphenylfluorindinone
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Zissimou, Georgia A., Kourtellaris, Andreas, Koutentis, Panayiotis A., Zissimou, Georgia A. [0000-0003-4821-9469], and Koutentis, Panayiotis A. [0000-0002-4652-7567]
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010405 organic chemistry ,Chemistry ,Organic Chemistry ,010402 general chemistry ,01 natural sciences ,Combinatorial chemistry ,0104 chemical sciences ,Characterization (materials science) - Abstract
Isodiphenylfluorindone 6 and isodiphenylfluorindinone 7 are synthesized. The former reacts with NaOMe to give the 13-methoxyisodiphenylfluorindone 22 (95%), while the latter reacts with 70% perchloric acid to give the bisperchlorate 21 (87%) and with MnO2 dimerizes to give 13,13′-bi(isodiphenylfluorindone) 4 (60%). UV–vis, NMR, CV, and DFT computational studies support the structural assignments of all products. Single-crystal X-ray diffraction studies are reported for isodiphenylfluorindinone 7. 83 8 4754 4761
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- 2018
7. Tetraphenylhexaazaanthracenes: 16π Weakly Antiaromatic Species with Singlet Ground States
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Constantinides, Christos P., Zissimou, Georgia A., Berezin, Andrey A., Ioannou, Theodosia A., Manoli, Maria, Tsokkou, Demetra, Theodorou, E., Hayes, Sophia C., Koutentis, Panayiotis Andreas, Hayes, Sophia C. [0000-0002-2809-6193], Koutentis, Panayiotis Andreas [0000-0002-4652-7567], Constantinides, Christos P. [0000-0001-6364-1102], and Zissimou, Georgia A. [0000-0003-4821-9469]
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Singlet ground state ,Chemistry ,Organic Chemistry ,Singlet state ,Physical and Theoretical Chemistry ,Photochemistry ,Biochemistry ,Fluorescence ,Antiaromaticity - Abstract
Tetraphenylhexaazaanthracene, TPHA-1, is a fluorescent zwitterionic biscyanine with a closed-shell singlet ground state. TPHA-1 overcomes its weak 16π antiaromaticity by partitioning its π system into 6π positive and 10π negative cyanines. The synthesis of TPHA-1 is low yielding and accompanied by two analogous TPHA isomers: the deep red, non-charge-separated, quinoidal TPHA-2, and the deep green TPHA-3 that partitions into two equal but oppositely charged 8π cyanines. The three TPHA isomers are compared. © 2015 American Chemical Society. 17 16 4026 4029 Cited By :5
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- 2015
8. 4H-1,2,6-Thiadiazin-4-one-containing small molecule donors and additive effects on their performance in solution-processed organic solar cells
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Hermerschmidt, F., Kalogirou, Andreas S., Min, J., Zissimou, Georgia A., Tuladhar, S. M., Ameri, T., Faber, H., Itskos, Grigorios, Choulis, Stelios A., Anthopoulos, T. D., Bradley, D. D. C., Nelson, J., Brabec, C. J., Koutentis, Panayiotis Andreas, Itskos, Grigorios [0000-0003-3971-3801], Koutentis, Panayiotis Andreas [0000-0002-4652-7567], Zissimou, Georgia A. [0000-0003-4821-9469], Kalogirou, Andreas S. [0000-0002-5476-5805], and Choulis, Stelios A. [0000-0002-7899-6296]
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Solar cells ,Systematic variation ,Electron mobility ,Fullerene ,Materials science ,Organic solar cell ,Technische Fakultät ,Silicones ,Bulk heterojunction solar cells ,Hole mobility ,Power conversion efficiencies ,Polymer solar cell ,Solution-processed ,Materials Chemistry ,Side chain ,Organic chemistry ,Alkyl ,chemistry.chemical_classification ,Energy conversion efficiency ,Donor acceptor donors ,technology, industry, and agriculture ,General Chemistry ,Electrical Engineering - Electronic Engineering - Information Engineering ,Acceptor ,Alkyl side chains ,Polydimethylsiloxane PDMS ,chemistry ,Chemical engineering ,Heterojunctions ,Engineering and Technology ,Fullerenes ,ddc:600 - Abstract
The optical, electrochemical, morphological and transport properties of a series of thiadiazinone (acceptor) and (thienyl)carbazoles (donor) containing π-extended donor-acceptor-donors (D-A-D) are presented. Systematic variations in the number of the thienyl units, the choice of branched or straight alkyl side chains and the use of a processing additive demonstrate their use as electron donors in bulk heterojunction solar cells blended with fullerene acceptors. The best power conversion efficiency (PCE) of 2.7% is achieved by adding to the D-A-D 3:fullerene blend a polydimethylsiloxane (PDMS) additive, that improves the morphology and doubles the hole mobility within the D-A-D:fullerene blend. © The Royal Society of Chemistry. 3 10 2358 2365 Cited By :7
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- 2015
9. Preparation of Blatter Radicals via Aza-Wittig Chemistry: The Reaction of N-Aryliminophosphoranes with 1-(Het)aroyl-2-aryldiazenes
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Savva, Anastasia C., Mirallai, Styliana I., Zissimou, Georgia A., Berezin, Andrey A., Demetriades, Marina, Kourtellaris, Andreas, Constantinides, Christos P., Nicolaides, C., Trypiniotis, Theodossis, Koutentis, Panayiotis Andreas, Koutentis, Panayiotis Andreas [0000-0002-4652-7567], Constantinides, Christos P. [0000-0001-6364-1102], Zissimou, Georgia A. [0000-0003-4821-9469], and Mirallai, Styliana I. [0000-0002-8195-8741]
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Diazenes ,Diphenyl ether ,010405 organic chemistry ,Radical ,Organic Chemistry ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,law.invention ,chemistry.chemical_compound ,Chemistry ,chemistry ,law ,Wittig reaction ,Organic compounds ,Organic chemistry ,Single crystal x-ray structures ,Electron paramagnetic resonance ,AKA - Abstract
Reacting N-aryliminophosphoranes with 1-(het)aroyl-2-aryldiazenes in preheated diphenyl ether at ca. 150-250 °C for 5-25 min affords in most cases the 1,3-diaryl-1,4-dihydrobenzo[e][1,2,4]triazin-4-yls (aka Blatter radicals) in moderate to good yields. All new compounds are fully characterized, including EPR and CV studies for the radicals. Single-crystal X-ray structures of 1-benzoyl-2-(perfluorophenyl)diazene and 1-(perfluorophenyl)-3-phenyl-1,4-dihydrobenzo[e][1,2,4]triazinyl are also presented. © 2017 American Chemical Society. 82 14 7564 7575
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- 2017
10. Emission from the stable Blatter radical
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Karecla, G., Papagiorgis, Panagiotis, Panagi, N., Zissimou, Georgia A., Constantinides, Christos P., Koutentis, Panayiotis Andreas, Itskos, Grigorios, Hayes, Sophia C., Hayes, Sophia C. [0000-0002-2809-6193], Itskos, Grigorios [0000-0003-3971-3801], Koutentis, Panayiotis Andreas [0000-0002-4652-7567], Constantinides, Christos P. [0000-0001-6364-1102], and Zissimou, Georgia A. [0000-0003-4821-9469]
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chemistry.chemical_classification ,010405 organic chemistry ,Chemistry ,Radical ,Quantum yield ,General Chemistry ,Polymer ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Fluorescence ,Catalysis ,0104 chemical sciences ,Materials Chemistry ,Thin film ,Ground state ,Absorption (electromagnetic radiation) ,Visible spectrum - Abstract
1,3-Diaryl-1,4-dihydro-1,2,4-benzotriazin-4-yls are air stable organic radicals which have been exploited for their interesting magnetic properties. Herein, we present the optical properties of the "parent" radical namely 1,3-diphenyl-1,4-dihydro-1,2,4-benzotriazin-4-yl (aka "the Blatter radical"), which possesses absorption bands that span the UV and visible spectrum that lead to broadband emission across the same spectral region. As shown in our experiments, the emission originates from excited electronic states of the radical, with, however, low quantum yield. Emission across the visible is also observed from thin films of the radical when inserted into PMMA matrices. As radical concentration within the polymer matrix is increased, systematic modifications in the spectral and temporal characteristics of the fluorescence indicate the formation of radical ground state aggregates. © 2017 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique. 41 16 8604 8613
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- 2017
11. A Magnetostructural Investigation of an Abrupt Spin Transition for 1-Phenyl-3-trifluoromethyl-1,4-dihydrobenzo[e][1,2,4]triazin-4-yl
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Constantinides, Christos P., Berezin, Andrey A., Zissimou, Georgia A., Manoli, Maria, Leitus, G. M., Bendikov, M., Probert, M. R., Rawson, J. M., Koutentis, Panayiotis Andreas, Constantinides, Christos P. [0000-0001-6364-1102], and Zissimou, Georgia A. [0000-0003-4821-9469]
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Low temperature phase ,cooling ,Spin transition ,cyclic potentiometry ,heating ,triazine derivative ,1 phenyl 3 tri fluoromethyl 1,4 dihydrobenzo[e][1,2,4]triazin 4 yl ,low temperature ,Biochemistry ,Catalysis ,high temperature ,Paramagnetism ,chemistry.chemical_compound ,Singlet ground state ,magnetometry ,First order transitions ,Colloid and Surface Chemistry ,Phase (matter) ,controlled study ,Noninteracting ,Weakly bound dimers ,density functional theory ,radical ,dimerization ,Structural phasis ,Trifluoromethyl ,Spins ,Condensed matter physics ,chemical interaction ,Chemistry ,article ,solid state ,General Chemistry ,dimer ,unclassified drug ,Crystallography ,phase transition ,High temperature phase ,Synthesis (chemical) ,magnetism ,chemical structure ,Diamagnetism ,entropy - Abstract
1-Phenyl-3-trifluoromethyl-1,4-dihydrobenzo[e][1,2,4]triazin-4-yl is the first example of a hydrazyl radical that shows a reversible sharp spin transition fully completed within 5(1) K. The nominally first-order transition takes place at ca. 58(2) K and proceeds via subtle changes of intra- and interstack interactions between two similar structural phases. The low-temperature phase (5-60 K) is diamagnetic and has a singlet ground state (2Jexp = -166.8 cm-1, gsolid = 2.0042, ρ = 0.2%) stemming from a multicenter two-electron interaction. The high-temperature phase (60-300 K) is paramagnetic as a result of noninteracting S = 1/2 spins arising from weakly bound dimers. © 2014 American Chemical Society. 136 34 11906 11909 Cited By :18
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- 2014
12. Discovery of anti-cancer activity for benzo[1,2,4]triazin-7-ones: Very strong correlation to pleurotin and thioredoxin reductase inhibition
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Sweeney, M., Coyle, R., Kavanagh, P., Berezin, Andrey A., Lo Re, D., Zissimou, Georgia A., Koutentis, Panayiotis Andreas, Carty, Michael P., Aldabbagh, Fawaz, ~|6201984|~, Koutentis, Panayiotis Andreas [0000-0002-4652-7567], and Zissimou, Georgia A. [0000-0003-4821-9469]
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Bioreduction ,Thioredoxin reductase ,1,3 diphenylbenzo[1,2,4]triazin 7 one ,6 (methylamino) 1,3 diphenylbenzo[1,2,4]triazin 7 one ,Clinical Biochemistry ,Pharmaceutical Science ,triazine derivative ,Reductase ,NCI-DTP COMPARE program ,01 natural sciences ,Biochemistry ,Anti-tumor ,chemistry.chemical_compound ,Drug Discovery ,Cytotoxicity ,Chimie pharmaceutique ,Périodiques ,enzyme inhibition ,antineoplastic agent ,Cell Line, Transformed ,chemistry.chemical_classification ,Heterocyclic compound ,MTT assay ,Triazines ,drug cytotoxicity ,thioredoxin reductase ,n (7 oxo 1,3 diphenyl 1,7 dihydrobenzo[1,2,4]triazin 6 yl)acetamide ,unclassified drug ,1 phenyl 3 (trifluoromethyl)benzo[1,2,4]triazin 7 one ,6 morpholino 1,3 diphenylbenzo[1,2,4]triazin 7 one ,Thioredoxin-Disulfide Reductase ,6 (diethylamino) 1,3 diphenylbenzo[1,2,4]triazin 7 one ,6 ethoxy 1,3 diphenylbenzo[1,2,4]triazin 7 one ,Molecular Medicine ,Thioredoxin ,1,3 diphenyl 6 (pyrrolidin 1 yl)benzo[1,2,4]triazin 7 one ,cancer cell line ,Stereochemistry ,growth ,Chemistry, Organic ,cyclic potentiometry ,Antineoplastic Agents ,010402 general chemistry ,6 methoxy 1,3 diphenylbenzo[1,2,4]triazin 7 one ,chemistry ,1,2,4 benzotriazine derivative ,Heterocyclic Compounds, 4 or More Rings ,Article ,Chimie bio-organique ,Humans ,transformed cell line ,controlled study ,Viability assay ,human ,drug screening ,Molecular Biology ,anthracene derivative ,antagonists and inhibitors ,lead ,Natural product ,Bioorganic chemistry ,010405 organic chemistry ,6 (ethylamino) 1,3 diphenylbenzo[1,2,4]triazin 7 one ,human cell ,Organic Chemistry ,fused heterocyclic rings ,toxicity ,assay ,drug development ,6 amino 1,3 diphenylbenzo[1,2,4]triazin 7 one ,0104 chemical sciences ,1,3 diphenyl 6 (piperidin 1 yl)benzo[1,2,4]triazin 7 one ,Chemistry, Clinical ,Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ,drug synthesis ,1,3 diphenyl 6 thiomorpholinobenzo[1,2,4]triazin 7 one ,matrix-assisted laser desorption-ionization mass spectrometry ,benzo[1,2,4]triazin 7 one derivative ,Drug Screening Assays, Antitumor ,Pharmaceutical chemistry ,oxidation reduction reaction ,pleurotin ,biological - Abstract
The thioredoxin (Trx)-thioredoxin reductase (TrxR) system plays a key role in maintaining the cellular redox balance with Trx being over-expressed in a number of cancers. Inhibition of TrxR is an important strategy for anti-cancer drug discovery. The natural product pleurotin is a well-known irreversible inhibitor of TrxR. The cytotoxicity data for benzo[1,2,4]triazin-7-ones showed very strong correlation (Pearson correlation coefficients ~0.8) to pleurotin using National Cancer Institute COMPARE analysis. A new 3-CF3 substituted benzo[1,2,4]triazin-7-one gave submicromolar inhibition of TrxR, although the parent compound 1,3-diphenylbenzo[1,2,4]triazin-7-one was more cytotoxic against cancer cell lines. Benzo[1,2,4]triazin-7-ones exhibited different types of reversible inhibition of TrxR, and cyclic voltammetry showed characteristic quasi-reversible redox processes. Cell viability studies indicated strong dependence of cytotoxicity on substitution at the 6-position of the 1,3-diphenylbenzo[1,2,4]triazin-7-one ring. F.A. thanks the Irish Research Council (IRC) for a Government of Ireland Postgraduate Scholarship for Martin Sweeney and College of Science, National University of Ireland Galway (NUI Galway) for a postgraduate scholarship for Robert Coyle. We thank the National Cancer Institute (USA), Development Therapeutic Program for providing us with a small quantity of pleurotin. P.A.K. thanks the Cyprus Research Promotion Foundation [Grants: NEAYPODOMH/NEKYP/0308/02 and YGEIA/BIOS/0308(BIE)/13], the University of Cyprus (Medium Sized Grant), and the following organizations in Cyprus for generous donations of chemicals and glassware: the State General Laboratory, the Agricultural Research Institute, the Ministry of Agriculture, Medochemie Ltd and Biotronics Ltd. Furthermore, P.A.K. thanks the A. G. Leventis Foundation for helping to establish the NMR facility in the University of Cyprus. peer-reviewed 2018-05-30
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- 2016
13. Erratum: Tetraphenylhexaazaanthracenes: 16π Weakly Antiaromatic Species with Singlet Ground States (Org. Lett. (2015) 17 (4026-4029) DOI: 10.1021/acs.orglett.5b01923)
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Constantinides, Christos P., Zissimou, Georgia A., Berezin, Andrey A., Ioannou, Theodosia A., Manoli, Maria, Tsokkou, Demetra, Theodorou, E., Hayes, Sophia C., Koutentis, Panayiotis Andreas, Hayes, Sophia C. [0000-0002-2809-6193], Koutentis, Panayiotis Andreas [0000-0002-4652-7567], Constantinides, Christos P. [0000-0001-6364-1102], and Zissimou, Georgia A. [0000-0003-4821-9469]
- Abstract
18 4
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- 2016
14. 5,6,7,8-Tetrafluoro-1-(2-nitrophenyl)-3-phenyl-1H-benzo[e][1,3,4]oxadiazine
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Zissimou, Georgia A., Kourtellaris, Andreas, Koutentis, Panayiotis A., Zissimou, Georgia A. [0000-0003-4821-9469], and Koutentis, Panayiotis A. [0000-0002-4652-7567]
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organic radical ,010405 organic chemistry ,nucleophilic aromatic substitution ,Organic Chemistry ,benzotriazine ,010402 general chemistry ,Hydrazide ,01 natural sciences ,Biochemistry ,Medicinal chemistry ,lcsh:QD146-197 ,cyclisation ,0104 chemical sciences ,chemistry.chemical_compound ,Acetic acid ,chemistry ,Nucleophilic aromatic substitution ,Yield (chemistry) ,oxadiazine ,Microwave irradiation ,lcsh:Inorganic chemistry ,Nitro ,halonitrobenzene ,Physical and Theoretical Chemistry ,hydrazide - Abstract
Treating 1-fluoro-2-nitrobenzene (6) with N′-pentafluorophenylbenzohydrazide (7) and K2CO3 (1.1 equiv) in EtOH at ca. 110 °C (sealed tube) for 24 h affords 5,6,7,8-tetrafluoro-1-(2-nitrophenyl)-3-phenyl-1H-benzo[e][1,3,4]oxadiazine (5) (36%) and N′-(2-nitrophenyl)-N′-(perfluorophenyl)benzohydrazide (3) (37%). The X-ray crystallography of 5,6,7,8-tetrafluoro-1-(2-nitrophenyl)-3-phenyl-1H-benzo[e][1,3,4]oxadiazine (5) is provided. Microwave irradiation (100 W) of perfluorophenylbenzohydrazide 3 with K2CO3 (1.1 equiv) in THF at ca. 120 °C (sealed tube, 80 PSI) for 3 h gives oxadiazine 5 (85%), while reduction of the nitro group using Sn (4 equiv) in glacial acetic acid at ca. 20 °C for 30 min, followed by cyclodehydration at ca. 118 °C for 20 min and treatment with 2 M NaOH for 24 h resulted in 1-(perfluorophenyl)-3-phenyl-1,2,4-benzotriazin-4-yl (4) with 93% yield.
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- 2018
15. Coordination Complexes of a Neutral 1,2,4-Benzotriazinyl Radical Ligand: Synthesis, Molecular and Electronic Structures, andMagnetic Properties
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Morgan, Ian S., Mansikkamäki, Akseli, Zissimou, Georgia A., Koutentis, Panayiotis Andreas, Rouzières, Mathieu, Clérac, Rodolphe, Tuononen, Heikki M., Nanoscience Center [Jyväskylä Univ] (NSC@JYU), University of Jyväskylä (JYU), Centre de recherches Paul Pascal (CRPP), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Koutentis, Panayiotis Andreas [0000-0002-4652-7567], and Zissimou, Georgia A. [0000-0003-4821-9469]
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Magnetic susceptibility measurements ,Antiferromagnetic coupling ,Iron compounds ,Ligands ,01 natural sciences ,Nickel ,heterosyklit ,Metal ions ,ta116 ,Cobalt compounds ,Chelation ,Chemistry ,Metal–radical interactions ,Magnetism ,Single crystal x-ray diffraction ,Radicals ,[CHIM.MATE]Chemical Sciences/Material chemistry ,metal-radical interactions ,radicals ,exchange interactions ,koordinaatiokemia ,Unpaired electron ,Positive ions ,Metals ,Synthesis (chemical) ,visual_art ,radikaalit ,visual_art.visual_art_medium ,Electronic structure ,Coordinating properties ,magneettiset ominaisuudet ,X ray diffraction ,Radical ,Inorganic chemistry ,Radical interactions ,Heterocycles ,010402 general chemistry ,Catalysis ,Magnetic susceptibility ,Metal ,Electronic structure calculations ,Metal complexes ,Magnetic properties ,[CHIM.COOR]Chemical Sciences/Coordination chemistry ,metalli-radikaali -vuorovaikutukset ,Manganese ,heterocycles ,010405 organic chemistry ,Ligand ,Crystal structure ,Organic Chemistry ,General Chemistry ,0104 chemical sciences ,Crystallography ,Octahedron ,Ferromagnetism ,Exchange interactions ,coordination chemistry ,Single crystals ,magnetic properties ,Coordination reactions - Abstract
A series of d-block metal complexes of the recently reported coordinating neutral radical ligand 1-phenyl-3-(pyrid-2-yl)-1,4-dihydro-1,2,4-benzotriazin-4-yl (1) was synthesized. The investigated systems contain the benzotriazinyl radical 1 coordinated to a divalent metal cation, MnII, FeII, CoII, or NiII, with 1,1,1,5,5,5-hexafluoroacetylacetonato (hfac) as the auxiliary ligand of choice. The synthesized complexes were fully characterized by single-crystal X-ray diffraction, magnetic susceptibility measurements, and electronic structure calculations. The complexes [Mn(1)(hfac)2] and [Fe(1)(hfac)2] displayed antiferromagnetic coupling between the unpaired electrons of the ligand and the metal cation, whereas the interaction was found to be ferromagnetic in the analogous NiII complex [Ni(1)(hfac)2]. The magnetic properties of the complex [Co(1)(hfac)2] were difficult to interpret owing to significant spin-orbit coupling inherent to octahedral high-spin CoII metal ion. As a whole, the reported data clearly demonstrated the favorable coordinating properties of the radical 1, which, together with its stability and structural tunability, make it an excellent new building block for establishing more complex metal-radical architectures with interesting magnetic properties. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. 21 44 15843 15853 Cited By :9
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- 2015
16. Erratum: Route to Benzo- and Pyrido-Fused 1,2,4-Triazinyl Radicals via N′-(Het)aryl-N′-[2-nitro(het)aryl]hydrazides (J. Org. Chem. (2014) 79:1 (314-327) DOI: 10.1021/jo402481t)
- Author
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Berezin, Andrey A., Zissimou, Georgia A., Constantinides, Christos P., Beldjoudi, Yassine, Rawson, J. M., Koutentis, Panayiotis Andreas, Koutentis, Panayiotis Andreas [0000-0002-4652-7567], Constantinides, Christos P. [0000-0001-6364-1102], and Zissimou, Georgia A. [0000-0003-4821-9469]
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Erratum ,error - Abstract
80 17 8943 8944 Cited By :2
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- 2015
17. ChemInform Abstract: Route to Benzo‐ and Pyrido‐Fused 1,2,4‐Triazinyl Radicals via N′‐(Het)aryl‐N′‐2‐nitro(het)aryl]hydrazides
- Author
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Berezin, Andrey A., Zissimou, Georgia A., Constantinides, Christos P., Beldjoudi, Yassine, Rawson, Jeremy M., Koutentis, Panayiotis Andreas, Koutentis, Panayiotis Andreas [0000-0002-4652-7567], Constantinides, Christos P. [0000-0001-6364-1102], and Zissimou, Georgia A. [0000-0003-4821-9469]
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Chemistry - Abstract
ID: 1074 In: ChemInform, Vol. 45, no. 23 ( 2014), p.no-no. Summary: Abstract A two‐step route to 1,3‐disubstituted benzo‐ and pyrido‐fused 1,2,4‐triazinyl radicals is presented.
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- 2014
18. Route to benzo- and pyrido-fused 1,2,4-triazinyl radicals via N'-(het)aryl-N'-[2-nitro(het)aryl]hydrazides
- Author
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Berezin, Andrey A., Zissimou, Georgia A., Constantinides, Christos P., Beldjoudi, Yassine, Rawson, J. M., Koutentis, Panayiotis Andreas, Koutentis, Panayiotis Andreas [0000-0002-4652-7567], Constantinides, Christos P. [0000-0001-6364-1102], and Zissimou, Georgia A. [0000-0003-4821-9469]
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Multi-step ,radical ,hydrazide derivative ,Stereochemistry ,Aryl ,Radical ,Organic Chemistry ,article ,dehydration ,nucleophilicity ,reduction ,Cyclo dehydrations ,Medicinal chemistry ,Alkali treatment ,Nitro group ,Chemistry ,chemistry.chemical_compound ,chemistry ,substitution reaction ,Nucleophilic aromatic substitution ,Organic compounds ,Nitro ,arylation - Abstract
A two-step route to 1,3-disubstituted benzo- and pyrido-fused 1,2,4-triazinyl radicals is presented. The route involves the N′-(2-nitroarylation) of easily prepared N′-(het)arylhydrazides via nucleophilic aromatic substitution of 1-halo-2-nitroarenes, which in most cases gives N′-(het)aryl-N′-[2-nitro(het)aryl]hydrazides in good yields. Mild reduction of the nitro group followed by an acid-mediated cyclodehydration gives the fused triazines, which upon alkali treatment afford the desired radicals. Fifteen examples of radicals are presented bearing a range of substituents at N-1, C-3, and C-7, including the pyrid-2-yl and 8-aza analogues. This route to the N′-(het)aryl-N′-[2-nitro(het)aryl]hydrazides, which works well with benzo- and picolinohydrazides, required a modification for aceto- and trifluoroacetohydrazides that involved a multistep synthesis of asymmetrically 1,1-diaryl-substituted hydrazines. © 2013 American Chemical Society. 79 1 314 327 Cited By :21
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- 2013
19. Novel BODIPY-based conjugated polymers donors for organic photovoltaic applications
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Economopoulos, Solon P., Chochos, Christos L., Ioannidou, Heraklidia A., Neophytou, Marios, Charilaou, C., Zissimou, Georgia A., Frost, J. M., Sachetan, T., Shahid, M., Nelson, J., Heeney, M., Bradley, D. D. C., Itskos, Grigorios, Koutentis, Panayiotis Andreas, Choulis, Stelios A., Itskos, Grigorios [0000-0003-3971-3801], Chochos, Christos L. [0000-0002-7783-157X], Choulis, Stelios A. [0000-0002-7899-6296], Zissimou, Georgia A. [0000-0003-4821-9469], Koutentis, Panayiotis Andreas [0000-0002-4652-7567], and Economopoulos, Solon P. [0000-0002-2609-4602]
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Low bandgap polymers ,Materials science ,Photoluminescence ,Band gap ,General Chemical Engineering ,Photovoltaic property ,Analytical chemistry ,Generation ,Conjugated system ,Electron ,Power conversion efficiencies ,chemistry.chemical_compound ,Fullerene ,Dyad ,Optoelectronic applications ,Moiety ,Quantum chemical calculations ,Heterojunction solar-cells ,Dyes ,chemistry.chemical_classification ,Copolymers ,Energy conversion efficiency ,Device performance ,General Chemistry ,Polymer ,Chromophore ,Blending ,Chromophores ,Open-circuit voltage ,chemistry ,Chemical engineering ,Organic photovoltaics ,Chemical Sciences ,BODIPY ,Conversion efficiency ,Natural Sciences ,Quantum chemistry ,Time-resolved photoluminescence ,Derivatives - Abstract
Five new polymers based on the 4,4'-difluoro-4-bora-3a,4a-diaza-s-indacene core (BODIPY) chromophore moiety have been synthesized as low bandgap polymers for optoelectronic applications. The polymers exhibited high solubility in common organic solvents and optical bandgaps ranging from 1.7-2 eV. The materials were characterized using NMR, UV-Vis, steady state and time-resolved photoluminescence and the energy levels were examined using electrochemistry and validated using quantum chemical calculations. Finally, a representative BODIPY derivative : PCBM blend was examined in terms of photovoltaic properties. Preliminary device performance parameters as a function of photo-active layer thickness and composition are reported and discussed, relating to power conversion efficiency values. © The Royal Society of Chemistry 2013. 3 26 10221 10229
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- 2013
20. The Suppression of Columnar π-Stacking in 3-Adamantyl-1-phenyl-1,4-dihydrobenzo[e][1,2,4]triazin-4-yl
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Constantinides, Christos P., Berezin, Andrey A., Zissimou, Georgia A., Manoli, Maria, Leitus, G. M., Koutentis, Panayiotis Andreas, Koutentis, Panayiotis Andreas [0000-0002-4652-7567], Constantinides, Christos P. [0000-0001-6364-1102], and Zissimou, Georgia A. [0000-0003-4821-9469]
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Models, Molecular ,Stereochemistry ,Radical ,paramagnet ,Stacking ,Pharmaceutical Science ,hydrazyls ,Crystallography, X-Ray ,Crystal packing ,010402 general chemistry ,01 natural sciences ,Article ,Analytical Chemistry ,lcsh:QD241-441 ,Paramagnetism ,Adamantyl ,lcsh:Organic chemistry ,Paramagnet ,Drug Discovery ,organic radicals ,Physical and Theoretical Chemistry ,Spin (physics) ,Spins ,Triazines ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Magnetic susceptibility ,1,2,4-benzotriazinyls ,adamantyl ,crystal packing ,0104 chemical sciences ,Crystallography ,Organic radicals ,Chemistry (miscellaneous) ,Hydrazyls ,Molecular Medicine ,Spin Labels - Abstract
3-Adamantyl-1-phenyl-1,4-dihydrobenzo[e][1,2,4]triazin-4-yl(4) crystallizes as chains of radicals where the spin bearing benzotriazinyl moieties are isolated from each other. Magnetic susceptibility studies in the 5-300 K temperature region indicate that radical 4 demonstrates typical paramagnetic behavior stemming from non-interacting S = 1/2 spins. © 2016 by the authors licensee MDPI. 21 5
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- 2016
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