1
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Gazagnaire E, Helminen J, King AWT, Golin Almeida T, Kurten T, Kilpeläinen I. Bicyclic guanidine superbase carboxylate salts for cellulose dissolution. RSC Adv 2024; 14:12119-12124. [PMID: 38628473 PMCID: PMC11019349 DOI: 10.1039/d4ra01734j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2024] [Accepted: 04/04/2024] [Indexed: 04/19/2024] Open
Abstract
Bicyclic guanidines are utilized in organic synthesis as base catalysts or reagents. They also offer a platform for coordination chemistry, for example in CO2 activation, and their carboxylate salts offer an efficient media for cellulose dissolution. We have studied a series of bicyclic guanidines with varying ring sizes and with varying methyl substituents with a specific aim to find hydrolytically stable acetate salts for dissolution and processing of cellulose. Different superbase synthesis pathways were tested, followed by hydrolytic stability and cellulose dissolution capacity tests. The synthesis pathways were designed to enable the scale up of the production of the superbases considering the availability of the starting molecules and the feasibility of the synthesis. As a result, we found several hydrolytically stable bicyclic guanidine structures, which can overcome many of the reoccurring problems as carboxylate salts or free bases.
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Affiliation(s)
- Eva Gazagnaire
- Department of Chemistry, Material Division, University of Helsinki FI-00560 Helsinki Finland
| | - Jussi Helminen
- Department of Chemistry, Material Division, University of Helsinki FI-00560 Helsinki Finland
| | - Alistair W T King
- VTT Technical Research Centre of Finland Ltd Tietotie 4e 02150 Espoo Finland
| | - Thomas Golin Almeida
- Institute for Atmospheric and Earth System Research/Chemistry, Faculty of Science FI-00560 Helsinki Finland
| | - Theo Kurten
- Institute for Atmospheric and Earth System Research/Chemistry, Faculty of Science FI-00560 Helsinki Finland
| | - Ilkka Kilpeläinen
- Department of Chemistry, Material Division, University of Helsinki FI-00560 Helsinki Finland
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2
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Alaboosh JMH, Hill SP, Kariuki BM, Redman JE. Crystal structures of sulfonamide protected bicyclic guanidines: ( S)-8-{[( tert-butyl-dimethyl-sil-yl)-oxy]meth-yl}-1-[(2,2,4,6,7-penta-methyl-2,3-di-hydro-benzo-furan-5-yl)sulfon-yl]-1,3,4,6,7,8-hexa-hydro-2 H-pyrimido[1,2- a]pyrimidin-1-ium tri-fluoro-methane-sulfonate and ( S)-8-(iodo-meth-yl)-1-tosyl-1,3,4,6,7,8-hexa-hydro-2 H-pyrimido[1,2- a]pyrimidin-1-ium iodide. Acta Crystallogr E Crystallogr Commun 2024; 80:305-309. [PMID: 38456050 PMCID: PMC10915657 DOI: 10.1107/s2056989024001129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Accepted: 02/01/2024] [Indexed: 03/09/2024]
Abstract
Two compounds, (S)-8-{[(tert-butyl-dimethyl-sil-yl)-oxy]meth-yl}-1-[(2,2,4,6,7-penta-methyl-2,3-di-hydro-benzo-furan-5-yl)sulfon-yl]-1,3,4,6,7,8-hexa-hydro-2H-pyrimido[1,2-a]pyrimidin-1-ium tri-fluoro-methane-sulfonate, C27H46N3O4SSi+·CF3O3S-, (1) and (S)-8-(iodo-meth-yl)-1-tosyl-1,3,4,6,7,8-hexa-hydro-2H-pyrimido[1,2-a]pyrimidin-1-ium iodide, C15H21IN3O2S+·I-, (2), have been synthesized and characterized. They are bicyclic guanidinium salts and were synthesized from N-(tert-but-oxy-carbon-yl)-l-me-thio-nine (Boc-l-Met-OH). The guanidine is protected by a 2,2,4,6,7-penta-methyl-dihydro-benzo-furan-5-sulfonyl (Pbf, 1) or a tosyl (2) group. In the crystals of both compounds, the guanidinium group is almost planar and the N-H forms an intra-molecular hydrogen bond in a six-membered ring to the oxygen atom of the sulfonamide protecting group.
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Affiliation(s)
- Jamal M. H. Alaboosh
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Steven P. Hill
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Benson M. Kariuki
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - James E. Redman
- School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
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3
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Evans MJ, Anker MD, McMullin CL, Coles MP. Reductive Coupling of a Diazoalkane Derivative Promoted by a Potassium Aluminyl and Elimination of Dinitrogen to Generate a Reactive Aluminium Ketimide. Chemistry 2023; 29:e202302903. [PMID: 37786384 PMCID: PMC10946750 DOI: 10.1002/chem.202302903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/27/2023] [Accepted: 09/28/2023] [Indexed: 10/04/2023]
Abstract
The reaction of 9-diazo-9H-fluorene (fluN2 ) with the potassium aluminyl K[Al(NON)] ([NON]2- =[O(SiMe2 NDipp)2 ]2- , Dipp=2,6-iPr2 C6 H3 ) affords K[Al(NON)(κN1 ,N3 -{(fluN2 )2 })] (1). Structural analysis shows a near planar 1,4-di(9H-fluoren-9-ylidene)tetraazadiide ligand that chelates to the aluminium. The thermally induced elimination of dinitrogen from 1 affords the neutral aluminium ketimide complex, Al(NON)(N=flu)(THF) (2) and the 1,2-di(9H-fluoren-9-yl)diazene dianion as the potassium salt, [K2 (THF)3 ][fluN=Nflu] (3). The reaction of 2 with N,N'-diisopropylcarbodiimide (iPrN=C=NiPr) affords the aluminium guanidinate complex, Al(NON){N(iPr)C(N=CMe2 )N(CHflu)} (4), showing a rare example of reactivity at a metal ketimide ligand. Density functional theory (DFT) calculations have been used to examine the bonding in the newly formed [(fluN2 )2 ]2- ligand in 1 and the ketimide bonding in 2. The mechanism leading to the formation of 4 has also been studied using this technique.
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Affiliation(s)
- Matthew J. Evans
- School of Chemical and Physical SciencesVictoria University of WellingtonP.O. Box 600Wellington6012New Zealand
| | - Mathew D. Anker
- School of Chemical and Physical SciencesVictoria University of WellingtonP.O. Box 600Wellington6012New Zealand
| | | | - Martyn P. Coles
- School of Chemical and Physical SciencesVictoria University of WellingtonP.O. Box 600Wellington6012New Zealand
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4
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Calabretta LO, Petri YD, Raines RT. Fluorescent Guanidinium-Azacarbazole for Oxoanion Binding in Water. J Org Chem 2023; 88:11694-11701. [PMID: 37530571 PMCID: PMC10530381 DOI: 10.1021/acs.joc.3c00982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/03/2023]
Abstract
Oxoanions such as carboxylates, phosphates, and sulfates play important roles in both chemistry and biology and are abundant on the cell surface. We report on the synthesis and properties of a rationally designed guanidinium-containing oxoanion binder, 1-guanidino-8-amino-2,7-diazacarbazole (GADAC). GADAC binds to a carboxylate, phosphate, and sulfate in pure water with affinities of 3.6 × 104, 1.1 × 103, and 4.2 × 103 M-1, respectively. Like 2-azacarbazole, which is a natural product that enables scorpions to fluoresce, GADAC is fluorescent in water (λabs = 356 nm, λem = 403 nm, ε = 13,400 M-1 cm-1). The quantum yield of GADAC is pH-sensitive, increasing from Φ = 0.12 at pH 7.4 to Φ = 0.53 at pH 4.0 as a result of the protonation of the aminopyridine moiety. The uptake of GADAC into live human melanoma cells is detectable in the DAPI channel at low micromolar concentrations. Its properties make GADAC a promising candidate for applications in oxoanion binding and fluorescence labeling in biological (e.g., the delivery of cargo into cells) and other contexts.
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Affiliation(s)
- Lindsey O. Calabretta
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Yana D. Petri
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Ronald T. Raines
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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5
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Pomikło D, Bodzioch A, Kaszyński P. 3-Substituted Blatter Radicals: Cyclization of N-Arylguanidines and N-Arylamidines to Benzo[ e][1,2,4]triazines and PhLi Addition. J Org Chem 2023; 88:2999-3011. [PMID: 36802654 PMCID: PMC9990070 DOI: 10.1021/acs.joc.2c02703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
A series of 3-amino- and 3-alkyl-substituted 1-phenyl-1,4-dihydrobenzo[e][1,2,4]triazin-4-yls was prepared in four steps involving N-arylation, cyclization of N-arylguanidines and N-arylamidines, reduction of the resulting N-oxides to benzo[e][1,2,4]triazines, and subsequent addition of PhLi followed by aerial oxidation. The resulting seven C(3)-substituted benzo[e][1,2,4]triazin-4-yls were analyzed by spectroscopic and electrochemical methods augmented with density functional theory (DFT) methods. Electrochemical data were compared to DFT results and correlated with substituent parameters.
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Affiliation(s)
- Dominika Pomikło
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90-363 Łódź, Poland
| | - Agnieszka Bodzioch
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90-363 Łódź, Poland
| | - Piotr Kaszyński
- Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences, 90-363 Łódź, Poland.,Faculty of Chemistry, University of Łódź, 91-403 Łódź, Poland.,Department of Chemistry, Middle Tennessee State University, 37132 Murfreesboro, Tennessee, United States
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6
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Mu PF, Zhang L, Bu R, Xiong LF, Liu YW, Gao EQ. Guanidine-Based Covalent Organic Frameworks: Cooperation between Cores and Linkers for Chromic Sensing and Efficient CO 2 Conversion. ACS APPLIED MATERIALS & INTERFACES 2023; 15:6902-6911. [PMID: 36694474 DOI: 10.1021/acsami.2c20510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
C(sp)-H carboxylation with CO2 is an attractive route of CO2 utilization and is traditionally promoted by transition metal catalysts, and organocatalysis for the conversion remains rarely explored and challenging. In this article, triaminoguanidine-derived covalent organic frameworks (COFs) were used as platforms to develop heterogeneous organocatalysts for the reaction. We demonstrated that the COFs with guanidine cores and pyrazine linkers show high catalytic performance as a result of the cooperation between cores and linkers. The core is vitally important, which is deprotonated to the guanidinato group that binds and activates CO2. The pyrazine linker collaborates with the core to activate the C(sp)-H bond through hydrogen bonding. In addition, the COFs show acid- and base-responsive chromic behaviors thanks to the amphoteric nature of the core and the auxochromic effect of the pyrazine linker. The work opens up new avenues to organocatalysts for C-H carboxylation and chromic materials for sensing and switching applications.
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Affiliation(s)
- Peng-Fei Mu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Lin Zhang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Ran Bu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Li-Fei Xiong
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - Ya-Wei Liu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
| | - En-Qing Gao
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China
- Institute of Eco-Chongming, Shanghai 202162, China
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7
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Conti R, Widera A, Müller G, Fekete C, Thöny D, Eiler F, Benkő Z, Grützmacher H. Organocatalyzed Phospha-Michael Addition: A Highly Efficient Synthesis of Customized Bis(acyl)phosphane Oxide Photoinitiators. Chemistry 2023; 29:e202202563. [PMID: 36200550 PMCID: PMC10100105 DOI: 10.1002/chem.202202563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Indexed: 11/05/2022]
Abstract
Addition of the P-H bond in bis(mesitoyl)phosphine, HP(COMes)2 (BAPH), to a wide variety of activated carbon-carbon double bonds as acceptors was investigated. While this phospha-Michael addition does not proceed in the absence of an additive or catalyst, excellent results were obtained with stoichiometric basic potassium or caesium salts. Simple amine bases can be employed in catalytic amounts, and tetramethylguanidine (TMG) in particular is an outstanding catalyst that allows the preparation of bis(acyl)phosphines, R-P(COMes)2 , under very mild conditions in excellent yields after only a short time. All phosphines RP(COMes)2 can subsequently be oxidized to the corresponding bis(acyl)phosphane oxides, RPO(COMes)2 , a substance class belonging to the most potent photoinitiators for radical polymerizations known to date. Thus, a simple and highly atom economic method has been found that allows the preparation of a broad range of photoinitiators adapted to their specific field of application even on a large scale.
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Affiliation(s)
- Riccardo Conti
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland
| | - Anna Widera
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland
| | - Georgina Müller
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland
| | - Csilla Fekete
- Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, 1111, Budapest, Műegyetem rakpart 3., Hungary
| | - Debora Thöny
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland
| | - Frederik Eiler
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland
| | - Zoltán Benkő
- Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, 1111, Budapest, Műegyetem rakpart 3., Hungary.,ELKH-BME Computation Driven Chemistry Research Group, 1111, Budapest, Műegyetem rakpart 3., Hungary
| | - Hansjörg Grützmacher
- Department of Chemistry and Applied Biosciences, ETH Zürich, Vladimir-Prelog-Weg 1-5/10, 8093, Zürich, Switzerland
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8
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Zhang Y, Lv C, Hu C, Su Z. Mechanistic Study of Asymmetric Alkynylation of Isatin-Derived Ketimine Mediated by a Copper/Guanidine Catalyst. J Org Chem 2022; 87:11693-11707. [PMID: 36001814 DOI: 10.1021/acs.joc.2c01321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this work, we performed a mechanistic study of asymmetric alkynylation of isatin-derived N-Boc ketimine that was first reported by Feng, Liu, and co-workers (Chem. Commun. 2018, 54, 678-681). Guanidine-amide promoted the formation of highly nucleophilic copper acetylene species by abstracting the terminal proton of phenylacetylene with an imine moiety. The guanidinium salt-Cu(I) complex was the most active species in the addition of the C═N bond, in which copper acetylene coordinated to the O atom of the amide moiety, and the isatin-derived ketimine substrate was activated by hydrogen bonding as well as tert-butoxycarbonyl···Cu(I) coordination. Due to weak interaction between Cu(I) and the Ph group in the amide of guanidine, as well as the repulsion between the tert-butyl group in ketimine and the cyclohexyl group in guanidine, the copper acetylene preferred to attack isatin-derived ketimine from the re-face, leading to the S-configuration product with excellent stereoselectivity. The affinity of the counterion for the Cu(I) center in the copper salt affected the deprotonation of phenylacetylene and the formation of guanidinium salt active species. In contrast to CuBr and CuCl, the combination of CuI with aniline-derived guanidine-amide exhibited high catalytic activity and a chiral induction effect, contributing to a high turnover frequency (9.70 × 10-4 s-1) in catalysis and ee%.
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Affiliation(s)
- Yan Zhang
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China
| | - Cidan Lv
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China
| | - Changwei Hu
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China
| | - Zhishan Su
- Key Laboratory of Green Chemistry and Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, P. R. China
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9
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New Guanidinium and Aminoguanidinim Salts of 2-Hydroxypyridine-3-carboxylic acid: Preparation and Spectral, Structural, Thermal, ADMET, Biological, and Molecular Docking Studies. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.133818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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10
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Kaur N, Rajput M, Bhardwaj P. Synthesis of heterocycles using guanidine: An overview. SYNTHETIC COMMUN 2022. [DOI: 10.1080/00397911.2022.2087045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Navjeet Kaur
- Department of Chemistry, Banasthali Vidyapith, Banasthali, India
| | - Mansi Rajput
- Department of Chemistry, Banasthali Vidyapith, Banasthali, India
| | - Pranshu Bhardwaj
- Department of Chemistry, Banasthali Vidyapith, Banasthali, India
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11
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Yang Z, Cao TT, Sun YF, Wu DS, Xu Y, Yang SH, Wang SQ, Wang L. Expeditious assembly of biuret-guanidine derivatives via the catalyst-free transformation. JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 2022; 24:259-267. [PMID: 35068269 DOI: 10.1080/10286020.2022.2027372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 01/06/2022] [Indexed: 06/14/2023]
Abstract
We disclose a mild and practical catalyst-free transformation for the expeditious construction of biuret-guanidine derivatives using aromatic isocyanates. This synthetic transformation is featured with mild reaction conditions and high efficiency.
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Affiliation(s)
- Zhen Yang
- Department of Traditional Chinese Medicine, Jilin Agricultural University, Changchun 130118, China
- Jilin Academy of Traditional Chinese Medical Science, Changchun 130021, China
| | - Ting-Ting Cao
- Department of Traditional Chinese Medicine, Jilin Agricultural University, Changchun 130118, China
- Institute of Medicinal Plant Development, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100193, China
| | - Yun-Fang Sun
- Institute of Medicinal Plant Development, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100193, China
| | - Dao-Shun Wu
- Institute of Medicinal Plant Development, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100193, China
| | - Yue Xu
- Department of Traditional Chinese Medicine, Jilin Agricultural University, Changchun 130118, China
| | - Shi-Hai Yang
- Department of Traditional Chinese Medicine, Jilin Agricultural University, Changchun 130118, China
| | - Shu-Qin Wang
- Jilin Academy of Traditional Chinese Medical Science, Changchun 130021, China
| | - Lei Wang
- Institute of Medicinal Plant Development, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100193, China
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12
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Schlapp-Hackl I, Witos J, Ojha K, Uusi-Kyyny P, Alopaeus V, Sixta H. Application-Related Consideration of the Thermal Stability of [mTBDH][OAc] Compared to Amidine-Based Ionic Liquids in the Presence of Various Amounts of Water. Ind Eng Chem Res 2022. [DOI: 10.1021/acs.iecr.1c04015] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Inge Schlapp-Hackl
- Department of Bioproducts and Biosystems, Aalto University, Vuorimiehentie 1, FI-02150 Espoo, Finland
| | - Joanna Witos
- Department of Bioproducts and Biosystems, Aalto University, Vuorimiehentie 1, FI-02150 Espoo, Finland
| | - Krishna Ojha
- Department of Bioproducts and Biosystems, Aalto University, Vuorimiehentie 1, FI-02150 Espoo, Finland
| | - Petri Uusi-Kyyny
- Department of Chemical and Metallurgical Engineering, Aalto University, Kemistintie 1, FI-02150 Espoo, Finland
| | - Ville Alopaeus
- Department of Chemical and Metallurgical Engineering, Aalto University, Kemistintie 1, FI-02150 Espoo, Finland
- Department of Chemical Engineering, Mid Sweden University, Holmgatan 10, SE-85170 Sundsvall, Sweden
| | - Herbert Sixta
- Department of Bioproducts and Biosystems, Aalto University, Vuorimiehentie 1, FI-02150 Espoo, Finland
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13
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Wani AA, Chourasiya SS, Kathuria D, Bharatam PV. 1,1-Diaminoazines as organocatalysts in phospha-Michael addition reactions. Chem Commun (Camb) 2021; 57:11717-11720. [PMID: 34697617 DOI: 10.1039/d1cc04657h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
1,1-Diaminoazines can act as effective organocatalysts for the formation of phosphorus-carbon bonds between biphenylphosphine oxide and an activated alkene (Michael acceptor). These catalysts provide the P-C adducts at a faster rate and with relatively better yields in comparison to the organocatalysts employed earlier. The notable advantage is that 1,1-diaminoazines catalyse the reaction even in an aqueous medium with very good yields. Organocatalysis using 1,1-diaminoazines was also successfully carried out between dimethylphosphite and benzylidenemalononitrile under multicomponent conditions.
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Affiliation(s)
- Aabid A Wani
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), SAS Nagar, Punjab, 160062, India.
| | - Sumit S Chourasiya
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), SAS Nagar, Punjab, 160062, India.
| | - Deepika Kathuria
- University Center for Research and Development, Department of Chemistry, Chandigarh University, Gharuan, Punjab 140413, India
| | - Prasad V Bharatam
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research (NIPER), SAS Nagar, Punjab, 160062, India.
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14
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Qiao L, Sun R, Tao Y, Yu C, Yan Y. Surface-confined guanidinium ionic liquid as a new type of stationary phase for hydrophilic interaction liquid chromatography. J Sep Sci 2021; 44:3357-3365. [PMID: 34270174 DOI: 10.1002/jssc.202100385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 07/11/2021] [Accepted: 07/13/2021] [Indexed: 11/05/2022]
Abstract
Guanidinium-based ionic liquids possess lower toxicity and greater designability than commonly used species and have presented good performances in liquid-phase extraction and stationary phase for capillary gas chromatography. In the present work, a novel type of surface-confined guanidinium ionic liquid stationary phase was developed by bonding a hexaalkylguanidinium ionic liquid N,N,N',N'-tetramethyl-N",N"-diallylguanidinium bromide onto the surface of 3-mercaptopropyl modified silica. The obtained surface-confined guanidinium ionic liquid silica materials were characterized by elemental analysis, infrared spectroscopy and thermogravimetric analysis, and then packed as a high-performance liquid chromatography column for the evaluation of chromatographic retention behavior. Typical polar compounds were used to evaluate the separation performances, and the changes of retention with water content in mobile phase further suggested the hydrophilic interaction liquid chromatography retention mechanism. Moreover, the effect of different chromatographic factors (salt concentration, mobile phase pH, and column temperature) on retention was investigated with a series of compounds as test solutes to gain insights into the retention mechanism. The results indicated that the surface-confined guanidinium ionic liquid stationary phase exhibited a hydrophilic interaction liquid chromatography/anion-exchange mixed-mode retention behavior and possessed promising potential in separating a wide range of compounds as an alternative stationary phase for high-performance liquid chromatography.
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Affiliation(s)
- Lizhen Qiao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, P. R. China.,School of Chemical Engineering, Dalian University of Technology, Panjin, P. R. China
| | - Ruiting Sun
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, P. R. China.,School of Chemical Engineering, Dalian University of Technology, Panjin, P. R. China
| | - Yuan Tao
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, P. R. China.,School of Chemical Engineering, Dalian University of Technology, Panjin, P. R. China
| | - Chunmei Yu
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, P. R. China.,School of Chemical Engineering, Dalian University of Technology, Panjin, P. R. China
| | - Yang Yan
- State Key Laboratory of Fine Chemicals, Dalian University of Technology, Dalian, P. R. China.,School of Chemical Engineering, Dalian University of Technology, Panjin, P. R. China
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15
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Auvray T, Pal AK, Hanan GS. Electronic Properties of Rhenium(I) Carbonyl Complexes Bearing Strongly Donating Hexahydro‐Pyrimidopyrimidine Based Ligands. Eur J Inorg Chem 2021. [DOI: 10.1002/ejic.202100028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Affiliation(s)
- Thomas Auvray
- Département de Chimie Université de Montréal, Complexe des Sciences, B-3419 1375 Avenue Thérèse-Lavoie-Roux Montréal QC H2V 0B3 Canada
| | - Amlan K. Pal
- Department of Chemistry Indian Institute of Technology Jammu, Jagti Campus Nagrota Bypass Road Jammu & Kashmir 181221 India
| | - Garry S. Hanan
- Département de Chimie Université de Montréal, Complexe des Sciences, B-3419 1375 Avenue Thérèse-Lavoie-Roux Montréal QC H2V 0B3 Canada
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16
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Steuer L, Kaifer E, Himmel HJ. On the metal-ligand bonding in dinuclear complexes with redox-active guanidine ligands. Dalton Trans 2021; 50:9467-9482. [PMID: 34136887 DOI: 10.1039/d1dt01354h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Coordination compounds with redox-active ligands are currently intensively studied. Within this research theme, redox-active guanidines have been established as a new, eminent class of redox-active ligands. In this work the variation of metal-guanidine bonding in dinuclear transition metal complexes with bridging redox-active tetrakisguanidine ligands is analysed. A series of dinuclear complexes with different metals (Mn, Fe, Co, Ni, Cu and Zn) is synthesized, using either newly prepared redox-active tetrakisguanidino-dioxine or previously reported tetrakisguanidino-benzene ligands. The discussion of the bond properties in this work is predominantly based on the trends of structural parameters, derived from determination of single-crystal structures by X-ray diffraction and quantum chemical calculations. In addition, the trends in the redox potentials and magnetometric (SQUID) measurements on some of the complexes are included. Due to their combined σ- and π-electron donor capability, redox-active guanidine ligands are weak-field ligands; the σ- and π-bonding contributions vary with the metal. The results highlight the peculiarity of copper-guanidine bonding with a high π-bond contribution to metal-guanidine bonding, enabled by structural distortion of the coordination mode from tetrahedral in the direction of square-planar, short copper-guanidine bonds and minor displacement of the copper atoms from the ligand aromatic plane.
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Affiliation(s)
- Lena Steuer
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
| | - Elisabeth Kaifer
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
| | - Hans-Jörg Himmel
- Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany.
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17
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Wilkinson E, Viguri F, Rodríguez R, López JA, García‐Orduña P, Lahoz FJ, Lamata P, Carmona D. Strained Ruthenium Complexes Bearing Tridentate Guanidine‐Derived Ligands. Helv Chim Acta 2021. [DOI: 10.1002/hlca.202100044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Eden‐Taylor Wilkinson
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) CSIC-Universidad de Zaragoza Departamento de Química Inorgánica Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Fernando Viguri
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) CSIC-Universidad de Zaragoza Departamento de Química Inorgánica Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Ricardo Rodríguez
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) CSIC-Universidad de Zaragoza Departamento de Química Inorgánica Pedro Cerbuna 12 50009 Zaragoza Spain
| | - José A. López
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) CSIC-Universidad de Zaragoza Departamento de Química Inorgánica Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Pilar García‐Orduña
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) CSIC-Universidad de Zaragoza Departamento de Química Inorgánica Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Fernando J. Lahoz
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) CSIC-Universidad de Zaragoza Departamento de Química Inorgánica Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Pilar Lamata
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) CSIC-Universidad de Zaragoza Departamento de Química Inorgánica Pedro Cerbuna 12 50009 Zaragoza Spain
| | - Daniel Carmona
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH) CSIC-Universidad de Zaragoza Departamento de Química Inorgánica Pedro Cerbuna 12 50009 Zaragoza Spain
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18
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Wang Y, Lu R, Yao J, Li H. 1,5,7-Triazabicyclo[4.4.0]dec-5-ene Enhances Activity of Peroxide Intermediates in Phosphine-Free α-Hydroxylation of Ketones. Angew Chem Int Ed Engl 2021; 60:6631-6638. [PMID: 33289252 DOI: 10.1002/anie.202014478] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 11/28/2020] [Indexed: 12/29/2022]
Abstract
The critical role of double hydrogen bonds was addressed for the aerobic α-hydroxylation of ketones catalyzed by 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), in the absence of either a metal catalyst or phosphine reductant. Experimental and theoretical investigations were performed to study the mechanism. In addition to initiating the reaction by proton abstraction, a more important role of TBD was revealed, that is, to enhance the oxidizing ability of peroxide intermediates, allowing DMSO to be used rather than commonly used phosphine reductants. Further characterizations with nuclear Overhauser effect spectroscopy (NOESY) confirmed the presence of double hydrogen bonds between TBD and the ketone, and kinetic studies suggested the attack of dioxygen on the TBD-enol adduct to be the rate-determining step. This work should encourage the application of TBD as a catalyst for oxidations.
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Affiliation(s)
- Yongtao Wang
- Department of Chemistry and ZJU-NHU United R&D Center, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China
| | - Rui Lu
- Department of Chemistry and ZJU-NHU United R&D Center, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China
| | - Jia Yao
- Department of Chemistry and ZJU-NHU United R&D Center, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China
| | - Haoran Li
- Department of Chemistry and ZJU-NHU United R&D Center, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China.,State Key Laboratory of Chemical Engineering and College of Chemical and Biological Engineering, Zhejiang University, 38 Zheda Road, Hangzhou, 310027, P. R. China
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19
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Wang Y, Lu R, Yao J, Li H. 1,5,7‐Triazabicyclo[4.4.0]dec‐5‐ene Enhances Activity of Peroxide Intermediates in Phosphine‐Free α‐Hydroxylation of Ketones. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202014478] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Yongtao Wang
- Department of Chemistry and ZJU-NHU United R&D Center Zhejiang University 38 Zheda Road Hangzhou 310027 P. R. China
| | - Rui Lu
- Department of Chemistry and ZJU-NHU United R&D Center Zhejiang University 38 Zheda Road Hangzhou 310027 P. R. China
| | - Jia Yao
- Department of Chemistry and ZJU-NHU United R&D Center Zhejiang University 38 Zheda Road Hangzhou 310027 P. R. China
| | - Haoran Li
- Department of Chemistry and ZJU-NHU United R&D Center Zhejiang University 38 Zheda Road Hangzhou 310027 P. R. China
- State Key Laboratory of Chemical Engineering and College of Chemical and Biological Engineering Zhejiang University 38 Zheda Road Hangzhou 310027 P. R. China
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20
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Wang CC, Qu YL, Liu XH, Ma ZW, Yang B, Liu ZJ, Chen XP, Chen YJ. Synthesis of Five-Membered Cyclic Guanidines via Cascade [3 + 2] Cycloaddition of α-Haloamides with Organo-cyanamides. J Org Chem 2021; 86:3546-3554. [PMID: 33538590 DOI: 10.1021/acs.joc.0c02932] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The convenient preparation of N2-unprotected five-membered cyclic guanidines was achieved through a cascade [3 + 2] cycloaddition between organo-cyanamides and α-haloamides under mild conditions in good to excellent yields (up to 99%). The corresponding cyclic guanidines could be easily transformed into hydantoins via hydrolysis.
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Affiliation(s)
- Chuan-Chuan Wang
- Faculty of Science, Henan University of Animal Husbandry and Economy, No. 146 Yingcai Street, Zhengzhou 450044, Henan, China.,College of Chemistry, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, Henan, China
| | - Ya-Li Qu
- School of Pharmaceutical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, Henan, China
| | - Xue-Hua Liu
- School of Pharmaceutical Sciences, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, Henan, China
| | - Zhi-Wei Ma
- Faculty of Science, Henan University of Animal Husbandry and Economy, No. 146 Yingcai Street, Zhengzhou 450044, Henan, China
| | - Bo Yang
- College of Chemistry, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, Henan, China
| | - Zhi-Jing Liu
- Faculty of Science, Henan University of Animal Husbandry and Economy, No. 146 Yingcai Street, Zhengzhou 450044, Henan, China
| | - Xiao-Pei Chen
- Faculty of Science, Henan University of Animal Husbandry and Economy, No. 146 Yingcai Street, Zhengzhou 450044, Henan, China
| | - Ya-Jing Chen
- School of Pharmaceutical Sciences, Key Laboratory of Advanced Drug Preparation Technologies, Ministry of Education of China; Co-innovation Center of Henan Province for New Drug R & D and Preclinical Safety, Zhengzhou University, 100 Science Avenue, Zhengzhou 450001, Henan, China
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21
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Kanth S, Nagaraja A, Puttaiahgowda YM. Polymeric approach to combat drug-resistant methicillin-resistant Staphylococcus aureus. JOURNAL OF MATERIALS SCIENCE 2021; 56:7265-7285. [PMID: 33518799 PMCID: PMC7831626 DOI: 10.1007/s10853-021-05776-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Accepted: 01/03/2021] [Indexed: 05/10/2023]
Abstract
ABSTRACT The current global death rate has threatened humans due to increase in deadly unknown infections caused by pathogenic microorganisms. On the contrary, the emergence of multidrug-resistant bacteria is also increasing which is leading to elevated lethality rate worldwide. Development of drug-resistant bacteria has become one of the daunting global challenges due to failure in approaching to combat against them. Methicillin-resistant Staphylococcus aureus (MRSA) is one of those drug-resistant bacteria which has led to increase in global mortality rate causing various lethal infections. Polymer synthesis can be one of the significant approaches to combat MRSA by fabricating polymeric coatings to prevent the spread of infections. This review provides last decade information in the development of various polymers against MRSA. GRAPHICAL ABSTRACT
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Affiliation(s)
- Shreya Kanth
- Department of Chemistry, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104 India
| | - Akshatha Nagaraja
- Department of Chemistry, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104 India
| | - Yashoda Malgar Puttaiahgowda
- Department of Chemistry, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104 India
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22
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Briš A, Glasovac Z, Margetić D. Gas-phase basicity of cyclic guanidine derivatives – a DFT study. NEW J CHEM 2021. [DOI: 10.1039/d0nj04589f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Density functional theory calculations (B3LYP) were employed in the study of gas-phase basicity (GB) and pKa of three different types of cyclic guanidines differing in the number of nitrogen atoms incorporated in rings.
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Affiliation(s)
- Anamarija Briš
- Laboratory for Physical-organic Chemistry, Division of Organic Chemistry and Biochemistry
- Ruđer Bošković Institute
- Zagreb
- Croatia
| | - Zoran Glasovac
- Laboratory for Physical-organic Chemistry, Division of Organic Chemistry and Biochemistry
- Ruđer Bošković Institute
- Zagreb
- Croatia
| | - Davor Margetić
- Laboratory for Physical-organic Chemistry, Division of Organic Chemistry and Biochemistry
- Ruđer Bošković Institute
- Zagreb
- Croatia
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23
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Aguirre Quintana LM, Jiang N, Bacsa J, La Pierre HS. Homoleptic cerium tris(dialkylamido)imidophosphorane guanidinate complexes. Dalton Trans 2020; 49:14908-14913. [PMID: 33078808 DOI: 10.1039/d0dt03472j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
We report the synthesis of a new potassium tris(piperdino)imidophosphorane N,N'-dicyclohexylguanidinate, K[CyGNP(pip)3], and describe the synthesis and characterization of the tris-homoleptic compounds, [Ce(CyGNP(pip)3)3], 1-Ce, and [Ce(CyGNP(pip)3)3][BPh4], 2-Ce. The latter is an unusual cationic tetravalent cerium complex. Cyclic voltammetry studies of 1-Ce and 2-Ce revealed Epc potentials of -1.56 V and -1.81 V, and Epa potentials of -0.78 V and -0.66 V (200 mV s-1; THF, vs. Fc0/+), respectively. Compounds 1-Ce and 2-Ce were studied by L3-edge X-ray absorption near-edge spectroscopy (XANES), and the fit of the spectrum of 2-Ce revealed a white-line multiplet with an nf value of 0.50(2).
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Affiliation(s)
- Luis M Aguirre Quintana
- Department of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA.
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24
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Meimoun J, Favrelle-Huret A, Bria M, Merle N, Stoclet G, De Winter J, Mincheva R, Raquez JM, Zinck P. Epimerization and chain scission of polylactides in the presence of an organic base, TBD. Polym Degrad Stab 2020. [DOI: 10.1016/j.polymdegradstab.2020.109188] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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25
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Ujjval R, Deepa M, Thomas JM, Sivasankar C, Thirupathi N. Unusual [Pt{κ 2( C, N)}] + → [Pt{κ 2( N, N)}] + Coordination Mode Flip of the Guanidinate(1−) Ligand in Cationic N, N′, N″-Tris(3,5-xylyl)guanidinatoplatinum(II) Bis(phosphine) Complexes. Syntheses, Structural and Theoretical Studies. Organometallics 2020. [DOI: 10.1021/acs.organomet.0c00408] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Rishabh Ujjval
- Department of Chemistry, University of Delhi, Delhi 110 007, India
| | - Masilamani Deepa
- Postgraduate and Research Department of Chemistry, Muthurangam Government Arts College (Autonomous), Vellore 632 002, Tamil Nadu, India
| | - Jisha Mary Thomas
- Catalysis and Energy Laboratory, Department of Chemistry, Pondicherry University (A Central University), R. V. Nagar, Kalapet, Pondicherry 605 014, India
| | - Chinnappan Sivasankar
- Catalysis and Energy Laboratory, Department of Chemistry, Pondicherry University (A Central University), R. V. Nagar, Kalapet, Pondicherry 605 014, India
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26
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Parker A, Lamata P, Viguri F, Rodríguez R, López JA, Lahoz FJ, García-Orduña P, Carmona D. Half-sandwich complexes of osmium containing guanidine-derived ligands. Dalton Trans 2020; 49:13601-13617. [PMID: 32975256 DOI: 10.1039/d0dt02713h] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Pyridinyl- and phosphano-guanidino complexes of formula [(η6-p-cymene)OsCl(H2L)][SbF6] (cymene = MeC6H4iPr; H2L = N,N'-bis(p-Tolyl)-N''-(2-pyridinylmethyl)guanidine, H2L1 (1) and N,N'-bis(p-Tolyl)-N''-(2-diphenylphosphanoethyl)guanidine, H2L2 (2)) have been prepared from the dimer [{(η6-p-cymene)OsCl}2(μ-Cl)2] and H2L in the presence of NaSbF6. Treatment of complex 2 with HCl renders the phosphano-guanidinium complex [(η6-p-cymene)OsCl2(H3L2)][SbF6] (3). Compounds 1 and 2 react with AgSbF6 rendering the cationic aqua complexes [(η6-p-cymene)Os(H2L)(OH2)][SbF6]2 (H2L = H2L1 (4), H2L2 (5)). Addition of monodentate ligands L to compound 4 affords complexes of formula [(η6-p-cymene)Os(H2L1)L][SbF6]2 (L = py (6), 4-(NHMe)py (7), CO (8), P(OMe)3 (9)). Treatment of complexes 4 and 5 with NaHCO3 renders the monocationic complexes [(η6-p-cymene)Os(κ3N,N',N''-HL1)][SbF6] (10) and [(η6-p-cymene)Os(κ3N,N',P-HL2)][SbF6] (11), respectively, in which the HL ligand adopts a fac-κ3 coordination mode. The new complexes have been characterised by analytical and spectroscopic means, including the determination of the crystal structures of the compounds 1-4, 6, 8, and 11, by X-ray diffractometric methods. The phosphano-guanidino complexes 2 and 5 exhibit a temperature dependent fluxional process in solution. The new 18 electron complexes 1, 2, 6, and 8-10 are active catalysts for the Friedel-Crafts reaction between trans-β-nitrostyrene and N-methyl-2-methylindole. Conversions greater than 90% were obtained. Proton NMR studies support a mechanism involving the Brønsted-acid activation of trans-β-nitrostyrene through the NH functionalities of the coordinated guanidine ligands.
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Affiliation(s)
- Amie Parker
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Pilar Lamata
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Fernando Viguri
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Ricardo Rodríguez
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - José A López
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Fernando J Lahoz
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Pilar García-Orduña
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
| | - Daniel Carmona
- Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC - Universidad de Zaragoza, Departamento de Química Inorgánica, Pedro Cerbuna 12, 50009 Zaragoza, Spain.
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27
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Kaiser S, Jandl J, Novak P, Schlögl S. Design and characterisation of vitrimer-like elastomeric composites from HXNBR rubber. SOFT MATTER 2020; 16:8577-8590. [PMID: 32766610 DOI: 10.1039/d0sm00362j] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The present study aims at the incorporation of vitrimer-like properties into elastomeric composites as a promising approach towards the sustainable production of rubber-based materials. In particular, hydrogenated carboxylated nitrile butadiene rubber (HXNBR), as a technically relevant high-performance rubber, is covalently cross-linked with epoxy group-functionalised calcium silicate (Esilicate) across its pending carboxylic acid moieties. Reaction with the reactive functions attached on the filler surface results in the formation of β-hydroxyl ester linkages at the HXNBR-Esilicate interface, which undergo thermo-activated transesterifications in the presence of a suitable catalyst. Topology rearrangements in the composites are confirmed by stress relaxation measurements at elevated temperatures. Comparison with an unfilled reference network reveals that the extent of stress relaxation can be mostly maintained upon the addition of the reactive filler even at large quantities. The Esilicate serves as both cross-linker and reinforcing filler, leading to a significant enhancement of the mechanical properties.
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Affiliation(s)
- Simon Kaiser
- Polymer Competence Center Leoben GmbH, Roseggerstrasse 12, A-8700 Leoben, Austria.
| | - Julius Jandl
- Polymer Competence Center Leoben GmbH, Roseggerstrasse 12, A-8700 Leoben, Austria.
| | - Patrick Novak
- Polymer Competence Center Leoben GmbH, Roseggerstrasse 12, A-8700 Leoben, Austria.
| | - Sandra Schlögl
- Polymer Competence Center Leoben GmbH, Roseggerstrasse 12, A-8700 Leoben, Austria.
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28
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Hylland KT, Øien‐Ødegaard S, Heyn RH, Tilset M. Zinc Schiff Base Complexes Derived from 2,2'‐Diaminobiphenyls: Solution Behavior and Reactivity towards Nitrogen Bases. Eur J Inorg Chem 2020. [DOI: 10.1002/ejic.202000589] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
| | - Sigurd Øien‐Ødegaard
- Department of Chemistry University of Oslo P. O. Box 1033 Blindern 0315 Oslo Norway
| | | | - Mats Tilset
- Department of Chemistry University of Oslo P. O. Box 1033 Blindern 0315 Oslo Norway
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29
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Ashraf MA, Li C, Norouzi F, Zhang D. New insights into the Lewis acidity of guanidinium species: Lewis acid interaction provides reactivity. CR CHIM 2020. [DOI: 10.5802/crchim.16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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30
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Fan C, Wen L, Cao X. A biphasic system based on guanidinium ionic liquid: Preparative separation of eicosapentaenoic acid ethyl ester and docosahexaenoic acid ethyl ester by countercurrent chromatography. J Chromatogr A 2020; 1618:460872. [PMID: 31959458 DOI: 10.1016/j.chroma.2020.460872] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 12/25/2019] [Accepted: 01/09/2020] [Indexed: 12/23/2022]
Abstract
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are high nutritional components. Evidence for unique effects of them is increasing. Further understanding of their independent biological functions urgently needs more efficient separation techniques. Nowadays, most of the commercially available fish oil products are the mixture of eicosapentaenoic acid ethyl ester (EPAEE) and docosahexaenoic acid ethyl ester (DHAEE). It will be convenient to directly separate esterified EPA and DHA without saponification pretreatment. However, it is of great challenge to separate EPAEE and DHAEE because of their extremely fat-soluble nature and the equivalent chain length rule. In this research, the suitability of green guanidinium ionic liquid (IL) in countercurrent chromatography (CCC) solvent system for the separation of them was evaluated for the first time. Compared with imidazolium IL and phosphonium IL, guanidinium IL based non-aqueous biphasic system showed more outstanding separation performance. The separation mechanism was elucidated in depth through quantum mechanical calculations. It was found that guanidinium IL acted a crucial role in the CCC separation, which resulted in difference of partition behavior of EPAEE and DHAEE via different hydrogen-bonding affinity. EPAEE and DHAEE were successfully separated by solvent system (n-heptane/methanol/propylguanidinium chloride ([C3Gun]Cl, 1:1:5%, v/v/m)) with high purity (>95%) in one step, which was not achieved beforehand. Moreover, an easy recycling procedure of IL had also been devised, which significantly reduced waste generated. It opens up a new way for reasonable design water-free two-phase solvent system for efficient separation of very non-polar lipid compounds.
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Affiliation(s)
- Chen Fan
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, NO. 11 Fucheng Road, Beijing 100048, China
| | - Lijiao Wen
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, NO. 11 Fucheng Road, Beijing 100048, China
| | - Xueli Cao
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, NO. 11 Fucheng Road, Beijing 100048, China.
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31
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Thakur V, Thirupathi N. Syntheses and structural aspects of dinuclear cycloplatinated N,N′,N″-triarylguanidinate(2−) complexes with a novel tridentate μ2-κ2(C,N):κ1N coordination mode. J Organomet Chem 2020. [DOI: 10.1016/j.jorganchem.2020.121138] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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32
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Singh H, Devi M, Jena N, Iqbal MM, Nailwal Y, De Sarkar A, Pal SK. Proton-Triggered Fluorescence Switching in Self-Exfoliated Ionic Covalent Organic Nanosheets for Applications in Selective Detection of Anions. ACS APPLIED MATERIALS & INTERFACES 2020; 12:13248-13255. [PMID: 32046492 DOI: 10.1021/acsami.9b20743] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The exfoliation of covalent organic frameworks into covalent organic nanosheets (CONs) not only helps to reduce fluorescence turn-off phenomena but also provides well-exposed active sites for fast response and recovery for various applications. The present work is an example of rational designing of a structure constructed by condensing triaminoguanidinium chloride (TGCl), an intrinsic ionic linker, with a fluorophore, 2, 5-dimethoxyterephthalaldehyde (DA), to produce highly fluorescent self-exfoliable ionic CONs (DATGCl-iCONs). These fluorescent iCONs are able to sense fluoride ions selectively down to the ppb level via the fluorescence turn-off mechanism. A closer look at the quenching mechanism via NMR, zeta potential measurement, lifetime measurement, and density functional theory calculations reveals unique proton-triggered fluorescence switching behavior of newly synthesized DATGCl-iCONs.
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Affiliation(s)
- Harpreet Singh
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, SAS Nagar, Mohali 140306, India
| | - Manisha Devi
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, SAS Nagar, Mohali 140306, India
| | - Nityasagar Jena
- Institute of Nano Science and Technology (INST), Phase 10, SAS Nagar, Mohali 160062, India
| | - Mohamed Musthafa Iqbal
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, SAS Nagar, Mohali 140306, India
| | - Yogendra Nailwal
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, SAS Nagar, Mohali 140306, India
| | - Abir De Sarkar
- Institute of Nano Science and Technology (INST), Phase 10, SAS Nagar, Mohali 160062, India
| | - Santanu Kumar Pal
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, SAS Nagar, Mohali 140306, India
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33
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Payne C, Kass SR. Structural considerations for charge‐enhanced Brønsted acid catalysts. J PHYS ORG CHEM 2020. [DOI: 10.1002/poc.4069] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Curtis Payne
- Department of Chemistry University of Minnesota Minneapolis MN USA
| | - Steven R. Kass
- Department of Chemistry University of Minnesota Minneapolis MN USA
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34
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Harnessing aromaticity to design of phosphazene and ylidophosphorane superbases: A theoretical study. COMPUT THEOR CHEM 2020. [DOI: 10.1016/j.comptc.2020.112714] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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35
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Rippel R, Pinheiro L, Lopes M, Lourenço A, Ferreira LM, Branco PS. Synthetic Approaches to a Challenging and Unusual Structure—An Amino-Pyrrolidine Guanine Core. Molecules 2020; 25:molecules25040797. [PMID: 32059504 PMCID: PMC7070370 DOI: 10.3390/molecules25040797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 02/07/2020] [Accepted: 02/10/2020] [Indexed: 11/22/2022] Open
Abstract
The synthesis of an unreported 2-aminopyrrolidine-1-carboxamidine unit is here described for the first time. This unusual and promising structure was attained through the oxidative decarboxylation of amino acids using the pair of reagents, silver(I)/peroxydisulfate (Ag(I)/S2O82−) followed by intermolecular (in the case of l-proline derivative) and intramolecular trapping (in the case of acyl l-arginine) by N-nucleophiles. The l-proline approach has a broader scope for the synthesis of 2-aminopyrrolidine-1-carboxamidine derivatives, whereas the intramolecular cyclization afforded by the l-acylarginines, when applied, results in higher yields. The former allowed the first synthesis of cernumidine, a natural alkaloid isolated in 2011 from Solanum cernuum Vell, as its racemic form.
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36
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Rao Kovvuri VR, Xue H, Romo D. Generation and Reactivity of 2-Amido-1,3-diaminoallyl Cations: Cyclic Guanidine Annulations via Net (3 + 2) and (4 + 3) Cycloadditions. Org Lett 2020; 22:1407-1413. [PMID: 32009413 DOI: 10.1021/acs.orglett.0c00019] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Toward a method for direct conversion of alkenes to cyclic guanidines, we report that 1,3-dipolar cycloadditions of 2-amido-1,3-diamino allylic cations with alkenes provide a new method for direct cyclic guanidine annulation. Generated under oxidative conditions, the 2-amido-1,3-diaminoallyl cations react as 1,3-dipoles providing rapid access to 2-amino imidazolines through net (3 + 2) cycloadditions. The utility is demonstrated through a concise synthesis of the oroidin alkaloid, phakellin. The described 1,3-dipole also participates in net (4 + 3) cycloadditions with dienes.
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Affiliation(s)
- V Raghavendra Rao Kovvuri
- Department of Chemistry and Biochemistry , Baylor University , One Bear Place #97348 , Waco , Texas 76798 , United States
| | - Haoran Xue
- Department of Chemistry and Biochemistry , Baylor University , One Bear Place #97348 , Waco , Texas 76798 , United States
| | - Daniel Romo
- Department of Chemistry and Biochemistry , Baylor University , One Bear Place #97348 , Waco , Texas 76798 , United States
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37
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Mesias-Salazar A, Trofymchuk OS, Daniliuc CG, Antiñolo A, Carrillo-Hermosilla F, Nachtigall FM, Santos LS, Rojas RS. Copper (II) as catalyst for intramolecular cyclization and oxidation of (1,4-phenylene)bisguanidines to benzodiimidazole-diylidenes. J Catal 2020. [DOI: 10.1016/j.jcat.2019.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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38
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Hosseini ST, Raissi H, Pakdel M. High-performance carbon dioxide capture and storage by multi-functional sphingosine kinase inhibitors through a CO2-philic membrane. NEW J CHEM 2020. [DOI: 10.1039/d0nj01231a] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Carbon dioxide (CO2) capture using environmentally friendly sphingosine-based materials was theoretically studied.
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Affiliation(s)
| | - Heidar Raissi
- Department of Chemistry
- Faculty of Science
- University of Birjand
- Birjand
- Iran
| | - Majid Pakdel
- Department of Chemistry
- Faculty of Science
- University of Birjand
- Birjand
- Iran
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39
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Komorski S, Leszczyński MK, Justyniak I, Lewiński J. Structural diversity of ethylzinc derivatives of 3,5-substituted pyrazoles. Dalton Trans 2020; 49:17388-17394. [PMID: 33211038 DOI: 10.1039/d0dt03026k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Equimolar reactions of Et2Zn with 3,5-dimethylpyrazole (H-pzMe2), 3,5-di-iso-propylpyrazole (H-pziPr2), 3,5-di-tert-butylpyrazole (H-pztBu2) and indazole (H-ind) were investigated in toluene or tetrahydrofuran (as a coordinating solvent). A series of diverse ethylzinc pyrazolates and indazolates were identified using advanced NMR spectroscopy and the single crystal X-ray diffraction techniques. The NMR experiments indicate that dimeric moieties of the general formula [EtZn(pz)]2 or [Et2Zn2(pz)2(THF)] are favoured in solution. Nevertheless, these types of complexes are kinetically labile and tend to undergo ligand scrambling reactions according to the Schlenk equilibrium. For example, the alkyl substituents in the pzMe2 and pziPr2 ligands do not appear to be a strong determinant of the dimeric moieties and the composition of the isolated complexes by crystallisation from the parent reaction mixture varies between spiro-type tri- and tetranuclear aggregates, [Et2Zn3(pz)4(THF)x] (x = 0 or 2) and [Et2Zn4(pz)6(THF)2], respectively. The nonstoichiometric formula of these organozinc derivatives is likely related to both the Schlenk-type equilibria and solubility of the respective moieties. In turn, the high steric demands of the 3,5-di-tert-butylpyrazolate ligand promote the dimeric form in solution and the solid state. Interestingly, the ethylzinc indazolate complex also does not undergo a redistribution reaction and yields a dimer.
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Affiliation(s)
- Szymon Komorski
- Department of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland.
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40
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41
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Cobalt-based catalysis for carboxylative cyclization of propargylic amines with CO2 at atmospheric pressure. J CO2 UTIL 2019. [DOI: 10.1016/j.jcou.2019.07.027] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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42
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Isothioureas, Ureas, and Their N-Methyl Amides from 2-Aminobenzothiazole and Chiral Amino Acids. Molecules 2019; 24:molecules24183391. [PMID: 31540462 PMCID: PMC6767222 DOI: 10.3390/molecules24183391] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2019] [Revised: 09/06/2019] [Accepted: 09/10/2019] [Indexed: 11/18/2022] Open
Abstract
In this investigation, the reaction of 2-dithiomethylcarboimidatebenzothiazole with a series of six chiral amino-acids was studied. The reaction proceeds through the isolable sodium salt of SMe-isothiourea carboxylates as intermediates, whose reaction with methyl iodide in stirring DMF as solvent affords SMe-isothiourea methyl esters. The presence of water in the reaction leads to the corresponding urea carboxylates as isolable intermediates, whose methyl esters were obtained. Finally, the urea N-methyl amide derivatives were isolated when SMe-isothiourea or urea methyl esters were reacted with methylamine in the presence of water. The structures of synthesized compounds were established by 1H and 13C nuclear magnetic resonance and the structures of SMe-isothiourea methyl esters derived from (l)-glycine, (l)-alanine, (l)-phenylglycine, and (l)-leucine, by X-ray diffraction analysis. This methodology allows to functionalize 2-aminobenzothiazole with SMe-isothiourea, urea, and methylamide groups derived from chiral amino acids to get benzothiazole derivatives containing coordination sites and hydrogen bonding groups. Further research on the biological activities of some of these derivatives is ongoing.
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43
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Kumar R, Ujjval R, Thirupathi N. Half Sandwich Electron Deficient
N
,
N′
,
N′′
‐Triarylguanidinatoruthenium(II) Complexes: Syntheses, Reactivity Studies, and Structural Aspects. Eur J Inorg Chem 2019. [DOI: 10.1002/ejic.201900616] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Robin Kumar
- Department of Chemistry University of Delhi Delhi 110 007 India
| | - Rishabh Ujjval
- Department of Chemistry University of Delhi Delhi 110 007 India
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44
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Kaiser S, Wurzer S, Pilz G, Kern W, Schlögl S. Stress relaxation and thermally adaptable properties in vitrimer-like elastomers from HXNBR rubber with covalent bonds. SOFT MATTER 2019; 15:6062-6072. [PMID: 31298258 DOI: 10.1039/c9sm00856j] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Widening the scope of skeletons in the chemistry of vitrimer(-like) high molecular weight rubbers, the present study highlights the preparation of vitrimer-like elastomers based on a technically relevant rubber that is characterised by high thermal and oxidation stability. In particular, we prepared covalently crosslinked hydrogenated carboxylated nitrile butadiene rubber (HXNBR) networks that can rearrange their topology due to the exchangeable nature of the crosslinks. By crosslinking with a di-functional epoxide, β-hydroxyl ester linkages are incorporated into the rubber, enabling thermo-activated transesterifications in the presence of the catalyst triazabicyclodecene. At moderate temperatures, the covalent linkages ensure good mechanical properties as well as chemical and thermal stability of the rubber, which is essential for most applications. In addition, bond exchange reactions allow for fast and distinctive stress relaxation at elevated temperatures. Due to the enhanced network mobility above the vitrification transition temperature, the materials exhibit thermally adaptable properties. A comparative study throughout all experiments with catalyst-free samples serving as a reference is made. Shape change experiments reveal a certain malleability of the HXNBR elastomers and improved adhesion properties are shown by means of lap shear tests. In the presence of catalyst, the failure mechanism changes from adhesive to cohesive failure proving the weldability of the material. Furthermore, the samples exhibit thermally triggered repair capabilities as demonstrated by stress-rupture tests. In general, it is shown that already low quantities of exchangeable crosslinks of associative nature impart a promising thermal adaptability into high molecular weight HXNBR rubber.
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Affiliation(s)
- Simon Kaiser
- Polymer Competence Center Leoben GmbH, Roseggerstrasse 12, A-8700 Leoben, Austria.
| | - Stefan Wurzer
- Institute of Materials Science and Testing of Polymers, Montanuniversitaet Leoben, Otto Glöckel-Strasse 2, A-8700 Leoben, Austria
| | - Gerald Pilz
- Institute of Materials Science and Testing of Polymers, Montanuniversitaet Leoben, Otto Glöckel-Strasse 2, A-8700 Leoben, Austria
| | - Wolfgang Kern
- Polymer Competence Center Leoben GmbH, Roseggerstrasse 12, A-8700 Leoben, Austria. and Institute of Chemistry of Polymeric Materials, Montanuniversitaet Leoben, Otto Glöckel-Strasse 2, A-8700 Leoben, Austria
| | - Sandra Schlögl
- Polymer Competence Center Leoben GmbH, Roseggerstrasse 12, A-8700 Leoben, Austria.
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45
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Francos J, Cadierno V. The chemistry of guanidinate complexes of the platinum group metals. Dalton Trans 2019; 48:9021-9036. [PMID: 31120072 DOI: 10.1039/c9dt01289c] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
In this Perspective article, recent advances in the chemistry of platinum group metal complexes containing mono- and dianionic guanidinate ligands, i.e. [(RN)2C-NR2]- and [(RN)2C[double bond, length as m-dash]NR]2-, respectively, are presented. Synthetic and structural aspects, reactivity studies, and applications of these compounds are discussed.
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Affiliation(s)
- Javier Francos
- Laboratorio de Compuestos Organometálicos y Catálisis (Unidad Asociada al CSIC), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Departamento de Química Orgánica e Inorgánica, IUQOEM, Facultad de Química, Universidad de Oviedo, Julián Clavería 8, E-33006 Oviedo, Spain.
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46
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"Intrinsic" Anion Exchange Polymers through the Dissociation of Strong Basic Groups: PPO with Grafted Bicyclic Guanidines. MEMBRANES 2019; 9:membranes9050057. [PMID: 31035646 PMCID: PMC6572084 DOI: 10.3390/membranes9050057] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 04/22/2019] [Accepted: 04/24/2019] [Indexed: 11/17/2022]
Abstract
We synthesized anion exchange polymers by a reaction of chloromethylated poly(2,6-dimethyl-1,4-phenylene)oxide (PPO) with strongly basic 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD). TBD contains secondary and tertiary amine groups in the guanidine portion. To favor the functionalization with the secondary amine, TBD was activated with butyl lithium. The yield of amine formation via the reaction of the benzyl chloride moiety with TBD was 85%. Furthermore, we prepared polymers with quaternary ammonium groups by the reaction of PPO-TBD with CH3I. The synthesis pathways and ionomer structure were investigated by NMR spectroscopy. The thermal decomposition of both ionomers, studied by thermogravimetry, started above 200 °C, corresponding to the loss of the basic group. The ion exchange capacities, water uptake and volumetric swelling are also reported. The “intrinsic” anion conductivity of PPO-TBD due to the dissociation of grafted TBD was in the order of 1 mS/cm (Cl form). The quaternized ionomer (PPO-TBD-Me) showed an even larger ionic conductivity, above 10 mS/cm at 80 °C in fully humidified conditions.
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47
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Doddi A, Peters M, Tamm M. N-Heterocyclic Carbene Adducts of Main Group Elements and Their Use as Ligands in Transition Metal Chemistry. Chem Rev 2019; 119:6994-7112. [PMID: 30983327 DOI: 10.1021/acs.chemrev.8b00791] [Citation(s) in RCA: 290] [Impact Index Per Article: 58.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
N-Heterocyclic carbenes (NHC) are nowadays ubiquitous and indispensable in many research fields, and it is not possible to imagine modern transition metal and main group element chemistry without the plethora of available NHCs with tailor-made electronic and steric properties. While their suitability to act as strong ligands toward transition metals has led to numerous applications of NHC complexes in homogeneous catalysis, their strong σ-donating and adaptable π-accepting abilities have also contributed to an impressive vitalization of main group chemistry with the isolation and characterization of NHC adducts of almost any element. Formally, NHC coordination to Lewis acids affords a transfer of nucleophilicity from the carbene carbon atom to the attached exocyclic moiety, and low-valent and low-coordinate adducts of the p-block elements with available lone pairs and/or polarized carbon-element π-bonds are able to act themselves as Lewis basic donor ligands toward transition metals. Accordingly, the availability of a large number of novel NHC adducts has not only produced new varieties of already existing ligand classes but has also allowed establishment of numerous complexes with unusual and often unprecedented element-metal bonds. This review aims at summarizing this development comprehensively and covers the usage of N-heterocyclic carbene adducts of the p-block elements as ligands in transition metal chemistry.
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Affiliation(s)
- Adinarayana Doddi
- Technische Universität Braunschweig, Institut für Anorganische und Analytische Chemie, Hagenring 30, 38106 Braunschweig, Germany
| | - Marius Peters
- Technische Universität Braunschweig, Institut für Anorganische und Analytische Chemie, Hagenring 30, 38106 Braunschweig, Germany
| | - Matthias Tamm
- Technische Universität Braunschweig, Institut für Anorganische und Analytische Chemie, Hagenring 30, 38106 Braunschweig, Germany
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48
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Casnati A, Perrone A, Mazzeo PP, Bacchi A, Mancuso R, Gabriele B, Maggi R, Maestri G, Motti E, Stirling A, Ca' ND. Synthesis of Imidazolidin-2-ones and Imidazol-2-ones via Base-Catalyzed Intramolecular Hydroamidation of Propargylic Ureas under Ambient Conditions. J Org Chem 2019; 84:3477-3490. [PMID: 30788963 DOI: 10.1021/acs.joc.9b00064] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The first organo-catalyzed synthesis of imidazolidin-2-ones and imidazol-2-ones via intramolecular hydroamidation of propargylic ureas is reported. The phosphazene base BEMP turned out to be the most active organo-catalyst compared with guanidine and amidine bases. Excellent chemo- and regioselectivities to five-membered cyclic ureas have been achieved under ambient conditions, with a wide substrate scope and exceptionally short reaction times (down to 1 min). A base-mediated isomerization step to an allenamide intermediate is the most feasible reaction pathway to give imidazol-2-ones, as suggested by DFT studies.
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Affiliation(s)
- Alessandra Casnati
- Department of Chemistry, Life Sciences and Environmental Sustainability , University of Parma , 43124 Parma , Italy
| | - Antonio Perrone
- Department of Chemistry, Life Sciences and Environmental Sustainability , University of Parma , 43124 Parma , Italy
| | - Paolo P Mazzeo
- Department of Chemistry, Life Sciences and Environmental Sustainability , University of Parma , 43124 Parma , Italy.,Biopharmanet-tec , Parco delle Scienze, 27/A , 43124 Parma , Italy
| | - Alessia Bacchi
- Department of Chemistry, Life Sciences and Environmental Sustainability , University of Parma , 43124 Parma , Italy.,Biopharmanet-tec , Parco delle Scienze, 27/A , 43124 Parma , Italy
| | - Raffaella Mancuso
- Dipartimento di Chimica e Tecnologie Chimiche , Università della Calabria , 87036 Arcavacata di Rende, Cosenza , Italy
| | - Bartolo Gabriele
- Dipartimento di Chimica e Tecnologie Chimiche , Università della Calabria , 87036 Arcavacata di Rende, Cosenza , Italy
| | - Raimondo Maggi
- Department of Chemistry, Life Sciences and Environmental Sustainability , University of Parma , 43124 Parma , Italy
| | - Giovanni Maestri
- Department of Chemistry, Life Sciences and Environmental Sustainability , University of Parma , 43124 Parma , Italy
| | - Elena Motti
- Department of Chemistry, Life Sciences and Environmental Sustainability , University of Parma , 43124 Parma , Italy
| | - András Stirling
- Theoretical Chemistry Research Group, Institute of Organic Chemistry , Research Centre for Natural Sciences , Budapest , Hungary
| | - Nicola Della Ca'
- Department of Chemistry, Life Sciences and Environmental Sustainability , University of Parma , 43124 Parma , Italy
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49
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He X, Ji Y, Peng C, Han B. Organocatalytic Asymmetric Synthesis of Cyclic Compounds Bearing a Trifluoromethylated Stereogenic Center: Recent Developments. Adv Synth Catal 2019. [DOI: 10.1002/adsc.201801647] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Xiang‐Hong He
- State Key Laboratory of Southwestern Chinese Medicine ResourcesChengdu University of Traditional Chinese Medicine Chengdu 611137 People's Republic of China
| | - Yan‐Ling Ji
- State Key Laboratory of Southwestern Chinese Medicine ResourcesChengdu University of Traditional Chinese Medicine Chengdu 611137 People's Republic of China
| | - Cheng Peng
- State Key Laboratory of Southwestern Chinese Medicine ResourcesChengdu University of Traditional Chinese Medicine Chengdu 611137 People's Republic of China
- Ministry of Education Key Laboratory of Standardization of Chinese Medicine, School of PharmacyChengdu University of Traditional Chinese Medicine Chengdu 611137 People's Republic of China
| | - Bo Han
- State Key Laboratory of Southwestern Chinese Medicine ResourcesChengdu University of Traditional Chinese Medicine Chengdu 611137 People's Republic of China
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50
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Dzienia A, Maksym P, Hachuła B, Tarnacka M, Biela T, Golba S, Zięba A, Chorążewski M, Kaminski K, Paluch M. Studying the catalytic activity of DBU and TBD upon water-initiated ROP of ε-caprolactone under different thermodynamic conditions. Polym Chem 2019. [DOI: 10.1039/c9py01134j] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Studies performed revealed that a novel catalytic system for water-initiated ε-CL ROP based on DBU protonation showed enhanced performance under high-pressure/high-temperature conditions.
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Affiliation(s)
- Andrzej Dzienia
- Institute of Chemistry
- University of Silesia
- 40-007 Katowice
- Poland
- Silesian Center of Education and Interdisciplinary Research
| | - Paulina Maksym
- Silesian Center of Education and Interdisciplinary Research
- University of Silesia
- 41-500 Chorzow
- Poland
- Institute of Physics
| | - Barbara Hachuła
- Institute of Chemistry
- University of Silesia
- 40-007 Katowice
- Poland
| | - Magdalena Tarnacka
- Silesian Center of Education and Interdisciplinary Research
- University of Silesia
- 41-500 Chorzow
- Poland
- Institute of Physics
| | - Tadeusz Biela
- Department of Polymer Chemistry
- Centre of Molecular and Macromolecular Studies
- Polish Academy of Sciences
- Lodz
- Poland
| | - Sylwia Golba
- Institute of Materials Science
- University of Silesia
- 41-500 Chorzow
- Poland
| | - Andrzej Zięba
- Department of Organic Chemistry
- Faculty of Pharmaceutical Sciences in Sosnowiec
- Medical University of Silesia in Katowice
- 41-200 Sosnowiec
- Poland
| | | | - Kamil Kaminski
- Silesian Center of Education and Interdisciplinary Research
- University of Silesia
- 41-500 Chorzow
- Poland
- Institute of Physics
| | - Marian Paluch
- Silesian Center of Education and Interdisciplinary Research
- University of Silesia
- 41-500 Chorzow
- Poland
- Institute of Physics
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