From c8b338c7cc8cf84efd2632af36d9d0c6c3c84e89 Mon Sep 17 00:00:00 2001 From: Pierre Beaujean Date: Mon, 3 Jun 2024 16:02:37 +0200 Subject: [PATCH] attempt at furbishing introduction --- Figure1.eps | Bin 14488 -> 16488 bytes biblio.bib | 316 ++++++++++++++++++++++++++++++++++++++++++++ im/nitroxides.cdxml | 52 ++++---- nitroxides.tex | 19 +-- 4 files changed, 352 insertions(+), 35 deletions(-) diff --git a/Figure1.eps b/Figure1.eps index efbaf577bdefdf6f21238f17e94646adaa94b99f..e83726ff8eb0a24fa8baedbfffada19faa7431e3 100644 GIT binary patch delta 1050 zcmY*YOKTHR6eiKsQcas!V@>+VRb$dNW-|BQx$|hNP*(-fCM&_FLP)zP!~~^?2!f$1 zTJRChMks~oP8Zf1LGU*Sf`1^(`shv&L>JyWcWxfcV$M0=cfRwT!_12t-|qS9=zPe` z(k#)5fiRw-7|qu!BLNd5Ti@Nx4^7zmGAdOorQ&*UUGBwdqY>p;p4=cD7Wot}YK>bD@NRGV_s z+Gq+cP2czC!Qbf(kJQ{wpL0jchS{c(@k=XwenIo@CBif;XXUCK*&-TP`ePv?j0!Z2 zH@nk)+(x&^M~N&RwhYJCn1d*@09zLW)!WtLb@)eZk1%MNmZf2asLf2x;cF}$;-AJ^ zwSr(bOBBl{rl}dYi*=wddAY+7r#l-oxRk-AEdF+-pcSTV31%`)H@YPJg{h80Zosmz zW)SX_3a9Xi&C1qX(Bz#CM{Mj_?7vxDSt}LG9giq~gkoJYyGXqbBhd@h@=691Mo@NP zwR~%JohxKS5tc%+gKkhy%msBuux9ZksJDbqYrEuA7(WE)rh@2QeWImb2A)<5ZqkNKiw9YK$~C1{-$dKd8$x AoB#j- delta 757 zcmaFSz&N8&;pm0S#}pVC7%D7)1RD7NpMhb5oq(ynk)ghkfsu)Vk(G(LLcl~naaL0k z1#|O_S%Lg==H{^q$@zK7i6y*T(S`~JKxn9-YYbGVYiMXO`6j;&lZoNv1}Uk@h62wa zOqI!Yf?FU=|H;lmeIRC{wA$pKLMvg+Q^MWm@ z`YD8|C@DL+R@-Xwe)Vr4MKCU(CYYNjtv*>-s|BK6WAbgSW~idgwc55|t05Y!H;d>p zf%y$U`)%}~;RRx9Pqx*Ecois9ZKO9@+@KR=2t=Xw_yVPTM+;XKXn6zB#hhJeC%wW_m_I-R5Rs-IE0@*^#s|8(LaSHk8$3H8uw7o}6t1PC!6! ez$CcLjV$#{fR>vWfGnT9z?K!LU1oBygD3!GKHIqf diff --git a/biblio.bib b/biblio.bib index 950df3d..1994cec 100644 --- a/biblio.bib +++ b/biblio.bib @@ -670,3 +670,319 @@ @article{hanschSurveyHammettSubstituent1991 urldate = {2024-05-24}, file = {/home/pierre/Zotero/storage/5HQ2AU8W/Hansch et al. - 1991 - A survey of Hammett substituent constants and reso.pdf} } + + +@article{leifertOrganicSynthesisUsing2023, + title = {Organic {{Synthesis Using Nitroxides}}}, + author = {Leifert, Dirk and Studer, Armido}, + year = {2023}, + month = aug, + journal = {Chemical Reviews}, + volume = {123}, + number = {16}, + pages = {10302--10380}, + publisher = {American Chemical Society}, + issn = {0009-2665}, + doi = {10.1021/acs.chemrev.3c00212}, + urldate = {2024-06-03}, + abstract = {Nitroxides, also known as nitroxyl radicals, are long-lived or stable radicals with the general structure R1R2N--O{$\bullet$}. The spin distribution over the nitroxide N and O atoms contributes to the thermodynamic stability of these radicals. The presence of bulky N-substituents R1 and R2 prevents nitroxide radical dimerization, ensuring their kinetic stability. Despite their reactivity toward various transient C radicals, some nitroxides can be easily stored under air at room temperature. Furthermore, nitroxides can be oxidized to oxoammonium salts (R1R2N=O+) or reduced to anions (R1R2N--O--), enabling them to act as valuable oxidants or reductants depending on their oxidation state. Therefore, they exhibit interesting reactivity across all three oxidation states. Due to these fascinating properties, nitroxides find extensive applications in diverse fields such as biochemistry, medicinal chemistry, materials science, and organic synthesis. This review focuses on the versatile applications of nitroxides in organic synthesis. For their use in other important fields, we will refer to several review articles. The introductory part provides a brief overview of the history of nitroxide chemistry. Subsequently, the key methods for preparing nitroxides are discussed, followed by an examination of their structural diversity and physical properties. The main portion of this review is dedicated to oxidation reactions, wherein parent nitroxides or their corresponding oxoammonium salts serve as active species. It will be demonstrated that various functional groups (such as alcohols, amines, enolates, and alkanes among others) can be efficiently oxidized. These oxidations can be carried out using nitroxides as catalysts in combination with various stoichiometric terminal oxidants. By reducing nitroxides to their corresponding anions, they become effective reducing reagents with intriguing applications in organic synthesis. Nitroxides possess the ability to selectively react with transient radicals, making them useful for terminating radical cascade reactions by forming alkoxyamines. Depending on their structure, alkoxyamines exhibit weak C--O bonds, allowing for the thermal generation of C radicals through reversible C--O bond cleavage. Such thermally generated C radicals can participate in various radical transformations, as discussed toward the end of this review. Furthermore, the application of this strategy in natural product synthesis will be presented.}, + file = {/home/pierre/Zotero/storage/GLKF4Q84/Leifert and Studer - 2023 - Organic Synthesis Using Nitroxides.pdf} +} + +@article{tebbenNitroxidesApplicationsSynthesis2011, + title = {Nitroxides: {{Applications}} in {{Synthesis}} and in {{Polymer Chemistry}}}, + shorttitle = {Nitroxides}, + author = {Tebben, Ludger and Studer, Armido}, + year = {2011}, + journal = {Angewandte Chemie International Edition}, + volume = {50}, + number = {22}, + pages = {5034--5068}, + issn = {1521-3773}, + doi = {10.1002/anie.201002547}, + urldate = {2024-06-03}, + abstract = {This Review describes the application of nitroxides to synthesis and polymer chemistry. The synthesis and physical properties of nitroxides are discussed first. The largest section focuses on their application as stoichiometric and catalytic oxidants in organic synthesis. The oxidation of alcohols and carbanions, as well as oxidative CC bond-forming reactions are presented along with other typical oxidative transformations. A section is also dedicated to the extensive use of nitroxides as trapping reagents for C-centered radicals in radical chemistry. Alkoxyamines derived from nitroxides are shown to be highly useful precursors of C-centered radicals in synthesis and also in polymer chemistry. The last section discusses the basics of nitroxide-mediated radical polymerization (NMP) and also highlights new developments in the synthesis of complex polymer architectures.}, + copyright = {Copyright {\copyright} 2011 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim}, + langid = {english}, + keywords = {functional materials,oxidation,polymerization,radical chemistry,synthetic methods}, + file = {/home/pierre/Zotero/storage/VPRUVIRX/Tebben and Studer - 2011 - Nitroxides Applications in Synthesis and in Polym.pdf;/home/pierre/Zotero/storage/W865Z9WC/anie.html} +} + + +@article{prescottBiologicalRelevanceFree2017, + title = {Biological {{Relevance}} of {{Free Radicals}} and {{Nitroxides}}}, + author = {Prescott, Christopher and Bottle, Steven E.}, + year = {2017}, + month = jun, + journal = {Cell Biochemistry and Biophysics}, + volume = {75}, + number = {2}, + pages = {227--240}, + issn = {1559-0283}, + doi = {10.1007/s12013-016-0759-0}, + urldate = {2024-06-03}, + abstract = {Nitroxides are stable, kinetically-persistent free radicals which have been successfully used in the study and intervention of oxidative stress, a critical issue pertaining to cellular health which results from an imbalance in the levels of damaging free radicals and redox-active species in the cellular environment. This review gives an overview of some of the biological processes that produce radicals and other reactive oxygen species with relevance to oxidative stress, and then discusses interactions of nitroxides with these species in terms of the use of nitroxides as redox-sensitive probes and redox-active therapeutic agents}, + langid = {english}, + keywords = {Aminoxyl,Antioxidant,Free radical,Nitroxide,Oxidative stress,Probe,Radical,Reactive oxygen species,Redox,ROS}, + file = {/home/pierre/Zotero/storage/JGY2FQB2/Prescott and Bottle - 2017 - Biological Relevance of Free Radicals and Nitroxid.pdf} +} + +@incollection{ernouldNitroxidesBatteryrelatedApplications2021, +author = {Ernould, B. and Gohy, J.-F.}, +isbn = {978-1-78801-752-7}, +title = "{Nitroxides in Battery-related Applications}", +booktitle = "{Nitroxides}", +publisher = {The Royal Society of Chemistry}, +year = {2021}, +month = {05}, +abstract = "{It is now well admitted in the battery research community that the next generation of batteries following this lithium-ion battery era should enable more sustainability with respect to energy storage. The heavy metal extraction and life cycle are some of the key problems that make the current technology one of the least green components of battery-powered devices. The path leading to more sustainability could trade the current heavy metal-based compounds for more abundant and eco-friendly elements, to make, for instance, organic-based electrodes. The aim of this chapter is to provide a comprehensive overview of nitroxide-based active materials for all-organic and organic hybrid batteries. Although there are many other electrode-related applications where they could shine, the category that will be highlighted in this chapter, namely organic radical polymers, will be mostly portrayed in the context of battery-related applications. In this context, not only the benefits of such approaches but also the challenges and limitations currently at play will be presented, since this is where the research should focus its efforts in order to bring them to the fore.}", +doi = {10.1039/9781788019651-00187}, +url = {https://doi.org/10.1039/9781788019651-00187}, +} + +@article{xieNitroxideRadicalPolymers2021, + title = {Nitroxide Radical Polymers for Emerging Plastic Energy Storage and Organic Electronics: Fundamentals, Materials, and Applications}, + shorttitle = {Nitroxide Radical Polymers for Emerging Plastic Energy Storage and Organic Electronics}, + author = {Xie, Yuan and Zhang, Kai and Yamauchi, Yusuke and Oyaizu, Kenichi and Jia, Zhongfan}, + year = {2021}, + month = mar, + journal = {Materials Horizons}, + volume = {8}, + number = {3}, + pages = {803--829}, + publisher = {The Royal Society of Chemistry}, + issn = {2051-6355}, + doi = {10.1039/D0MH01391A}, + urldate = {2024-06-03}, + abstract = {Increasing demand for portable and flexible electronic devices requires seamless integration of the energy storage system with other electronic components. This ever-growing area has urged on the rapid development of new electroactive materials that not only possess excellent electrochemical properties but hold capabilities to be fabricated to desired shapes. Ideally, these new materials should have minimal impact on the environment at the end of their life. Nitroxide radical polymers (NRPs) with their remarkable electrochemical and physical properties stand out from diverse organic redox systems and have attracted tremendous attention for their identified applications in plastic energy storage and organic devices. In this review, we present a comprehensive summary of NRPs with respect to the fundamental electrochemical properties, design principles and fabrication methods for different types of energy storage systems and organic electronic devices. While highlighting some exciting progress on charge transfer theory and emerging applications, we end up with a discussion on the challenges and opportunities regarding the future directions of this field.}, + langid = {english} +} + +@article{keDesigningStrategiesAdvanced2023, + title = {Designing Strategies of Advanced Electrode Materials for High-Rate Rechargeable Batteries}, + author = {Ke, Jiaqi and Zhang, Yufei and Wen, Zhipeng and Huang, Song and Ye, Minghui and Tang, Yongchao and Liu, Xiaoqing and Li, Cheng Chao}, + year = {2023}, + month = feb, + journal = {Journal of Materials Chemistry A}, + volume = {11}, + number = {9}, + pages = {4428--4457}, + publisher = {The Royal Society of Chemistry}, + issn = {2050-7496}, + doi = {10.1039/D2TA09502E}, + urldate = {2024-06-03}, + abstract = {Fast charging is considered to be a mainstream development area of rechargeable batteries with the exploitation of electric vehicle markets and portable electronics. Nevertheless, the limited range and long charging time of electric vehicles cause ``range anxiety'' for owners, which seriously hampers their widespread adoption. Because their performance is closely related to battery materials, structurally stable materials with high-rate performance and high specific capacity have become the key for the development of next-generation rechargeable batteries. This review provides an overview of advanced developed anode (Ti, Nb, carbon-based) and cathode (V-based and nitroxide radicals) materials and conductive polymer composite cathodes in rechargeable batteries in recent years and summarizes design strategies to achieve high-rate charging performance with long lifespans. The modified design strategies for overcoming the high-rate limitation of sluggish ion diffusion and low intrinsic conductivity mainly include surface coating, regulating morphology, creating defects, functionalizing group modification, chemical intercalating, and element doping. The development of charging protocols is also discussed. It is hoped that this review will provide practical information and guidance for the rational design of high-rate performance materials in the future.}, + langid = {english} +} + +@article{assummaNewConductingCopolymer2020, + title = {A {{New Conducting Copolymer Bearing Electro-Active Nitroxide Groups}} as {{Organic Electrode Materials}} for {{Batteries}}}, + author = {Assumma, L. and Kervella, Y. and Mouesca, J.-M. and Mendez, M. and Maurel, V. and Dubois, L. and Gutel, T. and Sadki, S.}, + year = {2020}, + journal = {ChemSusChem}, + volume = {13}, + number = {9}, + pages = {2419--2427}, + issn = {1864-564X}, + doi = {10.1002/cssc.201903313}, + urldate = {2024-06-03}, + abstract = {To reduce the amount of conducting additives generally required for polynitroxide-based electrodes, a stable radical (TEMPO) is combined with a conductive copolymer backbone consisting of 2,7-bisthiophene carbazole (2,7-BTC), which is characterized by a high intrinsic electronic conductivity. This work deals with the synthesis of this new polymer functionalized by a redox nitroxide. Fine structural characterization using electron paramagnetic resonance (EPR) techniques established that: 1) the nitroxide radicals are properly attached to the radical chain (continuous wave EPR) and 2) the polymer chain has very rigid conformations leading to a set of well-defined distances between first neighboring pairs of nitroxides (pulsed EPR). The redox group combined with the electroactive polymer showed not only a very high electrochemical reversibility but also a perfect match of redox potentials between the de-/doping reaction of the bisthiophene carbazole backbone and the redox activity of the nitroxide radical. This new organic electrode shows a stable capacity (about 60 mAh g-1) and enables a strong reduction in the amount of carbon additive due to the conducting-polymer skeleton.}, + copyright = {{\copyright} 2020 Wiley-VCH Verlag GmbH \& Co. KGaA, Weinheim}, + langid = {english}, + keywords = {batteries,conducting polymers,organic electrodes,redox reactions,TEMPO derivatives}, + file = {/home/pierre/Zotero/storage/75RN597G/Assumma et al. - 2020 - A New Conducting Copolymer Bearing Electro-Active .pdf} +} + +@article{friebeSustainableEnergyStorage2019, + title = {Sustainable {{Energy Storage}}: {{Recent Trends}} and {{Developments}} toward {{Fully Organic Batteries}}}, + shorttitle = {Sustainable {{Energy Storage}}}, + author = {Friebe, Christian and {Lex-Balducci}, Alexandra and Schubert, Ulrich S.}, + year = {2019}, + journal = {ChemSusChem}, + volume = {12}, + number = {18}, + pages = {4093--4115}, + issn = {1864-564X}, + doi = {10.1002/cssc.201901545}, + urldate = {2024-06-03}, + abstract = {In times of spreading mobile devices, organic batteries represent a promising approach to replace the well-established lithium-ion technology to fulfill the growing demand for small, flexible, safe, as well as sustainable energy storage solutions. In the last years, large efforts have been made regarding the investigation and development of batteries that use organic active materials since they feature superior properties compared to metal-based, in particular lithium-based, energy-storage systems in terms of flexibility and safety as well as with regard to resource availability and disposal. This Review compiles an overview over the most recent studies on the topic. It focuses on the different types of applied active materials, covering both known systems that are optimized and novel structures that aim at being established.}, + copyright = {{\copyright} 2019 The Authors. Published by Wiley-VCH Verlag GmbH \& Co. KGaA.}, + langid = {english}, + keywords = {electrochemistry,energy storage,hybrid metal-organic batteries,organic batteries,redox chemistry}, + file = {/home/pierre/Zotero/storage/TD7YV68P/Friebe et al. - 2019 - Sustainable Energy Storage Recent Trends and Deve.pdf} +} + +@article{nakaharaRechargeableBatteriesOrganic2002, + title = {Rechargeable Batteries with Organic Radical Cathodes}, + author = {Nakahara, K and Iwasa, S and Satoh, M and Morioka, Y and Iriyama, J and Suguro, M and Hasegawa, E}, + year = {2002}, + month = jun, + journal = {Chemical Physics Letters}, + volume = {359}, + number = {5}, + pages = {351--354}, + issn = {0009-2614}, + doi = {10.1016/S0009-2614(02)00705-4}, + urldate = {2024-06-03}, + abstract = {The first known application of stable radicals for energy storage systems is presented. A stable nitroxyl polyradical, poly (2,2,6,6-tetramethylpiperidinyloxy methacrylate) (PTMA) has been synthesized and applied to the cathode active materials in rechargeable batteries. These fabricated batteries have demonstrated an average discharge voltage of 3.5 V and a discharge capacity of 77 Ah/kg, which corresponds to 70\% of the theoretical capacity. It should be noted that the capacity remains unchanged for over 500 cycles of charging and discharging at a high current density of 1.0mA/cm2. Stable radicals promise to open new fields of use for plastic batteries.}, + file = {/home/pierre/Zotero/storage/MBKMV4CX/S0009261402007054.html} +} + + +@incollection{okaRadicalPolymersRechargeable2020a, + title = {Radical {{Polymers}} for {{Rechargeable Batteries}}}, + booktitle = {Redox {{Polymers}} for {{Energy}} and {{Nanomedicine}}}, + author = {Oka, Kouki and Nishide, Hiroyuki}, + editor = {Casado, Nerea and Mecerreyes, David}, + year = {2020}, + month = oct, + pages = {0}, + publisher = {The Royal Society of Chemistry}, + doi = {10.1039/9781788019743-00137}, + urldate = {2024-06-03}, + abstract = {Radical polymers are one of the redox polymers and bear robust radical molecules per repeating unit. Some of the radical polymers are characterized by the rapid and reversible one-electron redox ability of the radical sites. A typical example is poly(2,2,6,6-tetramethylpiperidinyloxy methacrylate), which has a very positive redox potential. The combination of the high density of radical redox sites and the amorphous plasticized state coexisting with a small quantity of electrolytes allows for a rapid self-exchange reaction among the sites driven by a steep concentration gradient, which leads to efficient charge transport and storage throughout the polymers. The chemical bistability of the reduced and oxidized species of radical polymers permits an ultimate energy density and durable cyclability during charging and discharging. Lithium-ion and all-organic batteries have thus been fabricated using radical polymers as electrode-active materials. The output voltage of the batteries is constant, corresponding to their redox potential difference, and can be tuned by the molecular design. The batteries provide burst power, which also allows instant full charging in a few seconds. The syntheses of radical polymers and various types of radical polymer batteries are described herein, with their future perspectives.}, + isbn = {978-1-78801-871-5} +} + +@article{sugaCathodeAnodeActivePoly2007, + title = {Cathode- and {{Anode-Active Poly}}(Nitroxylstyrene)s for {{Rechargeable Batteries}}:\, p- and n-{{Type Redox Switching}} via {{Substituent Effects}}}, + shorttitle = {Cathode- and {{Anode-Active Poly}}(Nitroxylstyrene)s for {{Rechargeable Batteries}}}, + author = {Suga, Takeo and Pu, Yong-Jin and Kasatori, Shinji and Nishide, Hiroyuki}, + year = {2007}, + month = may, + journal = {Macromolecules}, + volume = {40}, + number = {9}, + pages = {3167--3173}, + publisher = {American Chemical Society}, + issn = {0024-9297}, + doi = {10.1021/ma0628578}, + urldate = {2024-06-03}, + abstract = {Three polystyrenes bearing redox-active nitroxide radical(s) in each repeating unit, poly[4-(N-tert-butyl-N-oxylamino)styrene] (1), poly[3,5-di(N-tert-butyl-N-oxylamino)styrene] (2), and poly[4-(N-tert-butyl-N-oxylamino)-3-trifluoromethylstyrene] (3), were synthesized via free radical polymerization of protected precursor styrenic derivatives and subsequent chemical oxidation. The radicals in these polymers were robust at ambient conditions, and the polymers possessed radical densities of 2.97 {\texttimes} 1021, 4.27 {\texttimes} 1021, and 1.82 {\texttimes} 1021 unpaired electrons/g for 1-3, respectively, resulting in an electrode-active material with a high charge/discharge capacity. Particularly, the dinitroxide functional polymer 2 possessed the highest radical density. Cyclic voltammetry of the poly(nitroxylstyrene) 1 revealed a reversible redox at 0.74 V vs Ag/AgCl, which was assigned to the oxidation of the nitroxide radical to form the oxoammonium cation (p-type doped state). On the other hand, the poly(nitroxylstyrene) ortho-substituted with the electron-withdrawing trifluoromethyl group 3 showed a reversible redox at -0.76 V, ascribed to the n-type redox pair between the nitroxide radical and the aminoxy anion. Thus, the nitroxide radical polymer could be switched from p-type material suitable for a cathode to n-type material (anode-active) via altering the electron-withdrawing character of the substituents on the poly(nitroxylstyrene). This is the first report of an n-type radical polymer and the first report of using substituent effects to switch the redox behavior of the polymer. This versatile switching ability enables these polymers to function as components of metal-free electrodes in rechargeable batteries.}, + file = {/home/pierre/Zotero/storage/XGTKUQ63/Suga et al. - 2007 - Cathode- and Anode-Active Poly(nitroxylstyrene)s f.pdf} +} + +@article{wylieIncreasedStabilityNitroxide2019b, + title = {Increased Stability of Nitroxide Radicals in Ionic Liquids: More than a Viscosity Effect}, + shorttitle = {Increased Stability of Nitroxide Radicals in Ionic Liquids}, + author = {Wylie, Luke and Seeger, Zoe L. and Hancock, Amber N. and Izgorodina, Ekaterina I.}, + year = {2019}, + month = feb, + journal = {Physical Chemistry Chemical Physics}, + volume = {21}, + number = {6}, + pages = {2882--2888}, + publisher = {The Royal Society of Chemistry}, + issn = {1463-9084}, + doi = {10.1039/C8CP04854A}, + urldate = {2024-06-03}, + abstract = {Radical stability has been subject to continuous research due to its importance in polymerization as well as in all-organic batteries. Recently, the SOMO--HOMO conversion was identified as the main factor in controlling the stability of distonic radicals, for which the negative charge resides on the same molecule. Based on this finding, the idea of ionic liquids stabilizing radicals was hypothesized in this study. A series of ionic liquids were tested in EPR measurements of the 3-carboxy-2,2,5,5-tetramethyl-pyrroline-1-oxyl. Unusually high rotational diffusion constants ({$\tau$}R), 4 times larger compared to conventional media such as dichloromethane (DCM), were recorded at room temperature. This finding could only be explained by a strong interaction existing between the radical and ionic liquid ions, which was confirmed with quantum chemical calculations, with interaction energies falling between -17.1 kJ mol-1 for tetramethylphosphonium tetrafluoroborate and -85.6 kJ mol-1 for 1,3-dimethylimidazolium triflate. Elevated temperature measurements performed at 80 {$^\circ$}C reduced the viscosity of the ionic liquids to that of DCM, while the {$\tau$}R values remained relatively high, thus further confirming that the rotational hindrance occurred due to radical--ionic liquid interactions. The calculated interaction energies between the radical and ionic liquids ions were also found to correlate well with experimental rotational diffusion constants, thus offering us a valuable tool in tailoring ionic liquids for enhanced stability of nitroxide radicals. The findings of this study showcase the ability of ionic liquids to reduce reactivity of nitroxides without the need for any chemical modification of the radical.}, + langid = {english}, + file = {/home/pierre/Zotero/storage/TTLEI938/Wylie et al. - 2019 - Increased stability of nitroxide radicals in ionic.pdf} +} + +@article{armandIonicliquidMaterialsElectrochemical2009, + title = {Ionic-Liquid Materials for the Electrochemical Challenges of the Future}, + author = {Armand, Michel and Endres, Frank and MacFarlane, Douglas R. and Ohno, Hiroyuki and Scrosati, Bruno}, + year = {2009}, + month = aug, + journal = {Nature Materials}, + volume = {8}, + number = {8}, + pages = {621--629}, + publisher = {Nature Publishing Group}, + issn = {1476-4660}, + doi = {10.1038/nmat2448}, + urldate = {2024-06-03}, + abstract = {Ionic liquids are room-temperature molten salts, composed mostly of organic ions that may undergo almost unlimited structural variations. This review covers the newest aspects of ionic liquids in applications where their ion conductivity is exploited; as electrochemical solvents for metal/semiconductor electrodeposition, and as batteries and fuel cells where conventional media, organic solvents (in batteries) or water (in polymer-electrolyte-membrane fuel cells), fail. Biology and biomimetic processes in ionic liquids are also discussed. In these decidedly different materials, some enzymes show activity that is not exhibited in more traditional systems, creating huge potential for bioinspired catalysis and biofuel cells. Our goal in this review is to survey the recent key developments and issues within ionic-liquid research in these areas. As well as informing materials scientists, we hope to generate interest in the wider community and encourage others to make use of ionic liquids in tackling scientific challenges.}, + copyright = {2009 Springer Nature Limited}, + langid = {english}, + keywords = {Biomaterials,Condensed Matter Physics,general,Materials Science,Nanotechnology,Optical and Electronic Materials} +} + +@article{strehmelRadicalsIonicLiquids2012, + title = {Radicals in {{Ionic Liquids}}}, + author = {Strehmel, Veronika}, + year = {2012}, + journal = {ChemPhysChem}, + volume = {13}, + number = {7}, + pages = {1649--1663}, + issn = {1439-7641}, + doi = {10.1002/cphc.201100982}, + urldate = {2024-06-03}, + abstract = {Stable radicals and recombination of photogenerated lophyl radicals are investigated in ionic liquids. The 2,2,6,6-tetramethylpiperidine-1-yloxyl derivatives contain various substituents at the 4-position to the nitroxyl group, including hydrogen-bond-forming or ionic substituents that undergo additional interactions with the individual ions of the ionic liquids. Some of these spin probes contain similar ions to ionic liquids to avoid counter-ion exchange with the ionic liquid. Depending on the ionic liquid anion, the Stokes--Einstein theory or the Spernol--Gierer--Wirtz theory can be applied to describe the temperature dependence of the average rotational correlation time of the spin probe in the ionic liquids. Furthermore, the spin probes give information about the micropolarity of the ionic liquids. In this context the substituent at the 4-position to the nitroxyl group plays a significant role. Covalent bonding of a spin probe to the imidazolium ion results in bulky spin probes that are strongly immobilized in the ionic liquid. Furthermore, lophyl radical recombination in the dark, which is chosen to understand the dynamics of bimolecular reactions in ionic liquids, shows a slow process at longer timescale and a rise time at a shorter timescale. Although various reactions may contribute to the slower process during lophyl radical recombination, it follows a second-order kinetics that does not clearly show solvent viscosity dependence. However, the rise time, which may be attributed to radical pair formation, increases with increasing solvent viscosity.}, + copyright = {Copyright {\copyright} 2012 WILEY-VCH Verlag GmbH \& Co. KGaA, Weinheim}, + langid = {english}, + keywords = {ionic liquids,micropolarity,microviscosity,radicals,spin probes}, + file = {/home/pierre/Zotero/storage/4KSZANKE/Strehmel - 2012 - Radicals in Ionic Liquids.pdf} +} + +@article{torricellaNitroxideSpinLabels2021, + title = {Nitroxide Spin Labels and {{EPR}} Spectroscopy: {{A}} Powerful Association for Protein Dynamics Studies}, + shorttitle = {Nitroxide Spin Labels and {{EPR}} Spectroscopy}, + author = {Torricella, F. and Pierro, A. and Mileo, E. and Belle, V. and Bonucci, A.}, + year = {2021}, + month = jul, + journal = {Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics}, + volume = {1869}, + number = {7}, + pages = {140653}, + issn = {1570-9639}, + doi = {10.1016/j.bbapap.2021.140653}, + urldate = {2024-06-03}, + abstract = {Site-Directed Spin Labelling (SDSL) technique is based on the attachment of a paramagnetic label onto a specific position of a protein (or other bio-molecules) and the subsequent study by Electron Paramagnetic Resonance (EPR) spectroscopy. In particular, continuous-wave EPR (cw-EPR) spectra can detect the local conformational dynamics for proteins under various conditions. Moreover, pulse-EPR experiments on doubly spin-labelled proteins allow measuring distances between spin centres in the 1.5--8~nm range, providing information about structures and functions. This review focuses on SDSL-EPR spectroscopy as a structural biology tool to investigate proteins using nitroxide labels. The versatility of this spectroscopic approach for protein structural characterization has been demonstrated through the choice of recent studies. The main aim is to provide a general overview of the technique, particularly for non-experts, to spread the applicability of this technique in various fields of structural biology.}, + keywords = {DEER,EPR,In-cell EPR,Nitroxide radicals,SDSL}, + file = {/home/pierre/Zotero/storage/UWE4Q7GU/S1570963921000595.html} +} + + +@article{xiaoMolecularDebyeHuckelApproach2014, + title = {A Molecular {{Debye-H{\"u}ckel}} Approach to the Reorganization Energy of Electron Transfer Reactions in an Electric Cell}, + author = {Xiao, Tiejun and Song, Xueyu}, + year = {2014}, + month = oct, + journal = {The Journal of Chemical Physics}, + volume = {141}, + number = {13}, + pages = {134104}, + issn = {0021-9606}, + doi = {10.1063/1.4896763}, + urldate = {2024-06-03}, + abstract = {Electron transfer near an electrode immersed in ionic fluids is studied using the linear response approximation, namely, mean value of the vertical energy gap can be used to evaluate the reorganization energy, and hence any linear response model that can treat Coulomb interactions successfully can be used for the reorganization energy calculation. Specifically, a molecular Debye-H{\"u}ckel theory is used to calculate the reorganization energy of electron transfer reactions in an electric cell. Applications to electron transfer near an electrode in molten salts show that the reorganization energies from our molecular Debye-H{\"u}ckel theory agree well with the results from MD simulations.}, + file = {/home/pierre/Zotero/storage/YTRZEB7C/Xiao and Song - 2014 - A molecular Debye-Hückel approach to the reorganiz.pdf;/home/pierre/Zotero/storage/4KK5CRXD/A-molecular-Debye-Huckel-approach-to-the.html} +} + +@article{xiaoReorganizationEnergyElectron2013, + title = {Reorganization Energy of Electron Transfer Processes in Ionic Fluids: {{A}} Molecular {{Debye-H{\"u}ckel}} Approach}, + shorttitle = {Reorganization Energy of Electron Transfer Processes in Ionic Fluids}, + author = {Xiao, Tiejun and Song, Xueyu}, + year = {2013}, + month = mar, + journal = {The Journal of Chemical Physics}, + volume = {138}, + number = {11}, + pages = {114105}, + issn = {0021-9606}, + doi = {10.1063/1.4794790}, + urldate = {2024-06-03}, + abstract = {The reorganization energy of electron transfer processes in ionic fluids is studied under the linear response approximation using a molecule Debye-H{\"u}ckel theory. Reorganization energies of some model reactants of electron transfer reactions in molten salts are obtained from molecular simulations and a molecule Debye-H{\"u}ckel approach. Good agreements between simulation results and the results from our theoretical calculations using the same model Hamiltonian are found. Applications of our theory to electron transfer reactions in room temperature ionic liquids further demonstrate that our theoretical approach presents a reliable and accurate methodology for the estimation of reorganization energies of electron transfer reactions in ionic fluids.}, + file = {/home/pierre/Zotero/storage/2GBQM37I/Xiao and Song - 2013 - Reorganization energy of electron transfer process.pdf;/home/pierre/Zotero/storage/RQDM7K5V/Reorganization-energy-of-electron-transfer.html} +} + +@article{marcusIonPairing2006, + title = {Ion {{Pairing}}}, + author = {Marcus, Yizhak and Hefter, Glenn}, + year = {2006}, + month = nov, + journal = {Chemical Reviews}, + volume = {106}, + number = {11}, + pages = {4585--4621}, + publisher = {American Chemical Society}, + issn = {0009-2665}, + doi = {10.1021/cr040087x}, + urldate = {2024-04-17}, + file = {/home/pierre/Zotero/storage/DS7YGMCH/Marcus and Hefter - 2006 - Ion Pairing.pdf} +} + diff --git a/im/nitroxides.cdxml b/im/nitroxides.cdxml index bb3569d..dc15917 100644 --- a/im/nitroxides.cdxml +++ b/im/nitroxides.cdxml @@ -3,8 +3,8 @@ + e-oxamonium -cationoxoammonium +cation (N+)nitroxide -radicalnitroxide +radical (N.)hydroxylamine -anionhydroxylamine +anion (N-)$\ce{N-O^.}, also shortened in \ce{N^.} in this article), which can be oxidized to the oxammonium cation ($>$\ce{N+=O}, abbreviated \ce{N+}) or reduced to the hydroxylamine anion ($>$\ce{N-O-}, abbreviated \ce{N-}), as depicted in Fig.~\ref{fig:states}\todo{add he notation \ce{N+}, \ce{N^.}, and \ce{N-}. Also, oxa\textbf{m}monium!}. The remarkable stability of the nitroxide radical arises from the delocalization of the unpaired electron over the nitrogen and oxygen atoms, combined with the steric protection provided by the substituents. Beyond their application in batteries, nitroxides have been extensively studied and utilized in various fields. They serve as spin labels in electron paramagnetic resonance (EPR) spectroscopy, as mediators for controlled radical polymerizations in polymer chemistry, and as antioxidants in biological systems \cite{souleChemistryBiologyNitroxide2007,lewandowskiNitroxidesAntioxidantsAnticancer2017}.\todo{And \cite{jiAirStableOrganicRadicals2020}.} +Nitroxides are organic compounds containing the nitroxyl/aminoxyl radical functional group \cite{berlinerHistoryUseNitroxides2012}. This group can exist in three redox states: the nitroxide radical ($>$\ce{N-O^.}, also shortened in \ce{N^.} in this article), which can be oxidized to the oxoammonium cation ($>$\ce{N+=O}, abbreviated \ce{N+}) or reduced to the hydroxylamine anion ($>$\ce{N-O-}, abbreviated \ce{N-}), as depicted in Fig.~\ref{fig:states}. The remarkable stability of the nitroxide radical arises from the delocalization of the unpaired electron over the nitrogen and oxygen atoms, combined with the steric protection provided by the substituents, and environmental effects due to the interaction with solvent and ions \cite{grynovaOriginScopeLongRange2013,grynovaSwitchingRadicalStability2013}. \begin{figure}[!h] \centering \includegraphics[width=.5\linewidth]{Figure1} - \caption{Oxidized (left) and reduced (right) form of the the nitroxide radical (center).} + \caption{Oxidized (left) and reduced (right) forms of the the nitroxide radical (center).} \label{fig:states} \end{figure} -The performance of nitroxide-based batteries is influenced by solvation and the nature of the electrolytes used. Solvation effects can alter the electronic environment of nitroxide radicals, thereby affecting their redox potentials and reactivity. Additionally, the choice of electrolyte impacts ion transport, redox stability, and the overall efficiency of the battery. Understanding the interplay between nitroxides, solvents, and electrolytes is therefore crucial for the rational design of high-performance batteries. Computational studies using quantum chemical methods provide valuable insights into solvation effects, allowing for the prediction and tuning of redox properties.\todo{more!} +The performance of nitroxide-based batteries is influenced by substitents \cite{sugaCathodeAnodeActivePoly2007}, by solvation, and the nature of the electrolytes used, in particular in ionic liquids \cite{armandIonicliquidMaterialsElectrochemical2009,strehmelRadicalsIonicLiquids2012,wylieIncreasedStabilityNitroxide2019b}. Understanding the interplay between nitroxides, solvents, and electrolytes is therefore crucial for the rational design of high-performance batteries. Computational studies using quantum chemical methods provide valuable insights into solvation effects, allowing for the prediction and tuning of redox properties. While the seminal studies of Coote and co-workers \cite{hodgsonOneElectronOxidationReduction2007,blincoExperimentalTheoreticalStudies2008} have focused on the impact of substituent on the redox potential, latter investigations by other groups have also considered the impact of electrolytes, and of the different (electrostatic, but not only) interactions between the two \cite{matsuiDensityFunctionalTheory2013,zhangInteractionsImidazoliumBasedIonic2016,zhangEffectHeteroatomFunctionality2018,wylieImprovedPerformanceAllOrganic2019a}. From a phenomenological point of view, two different approaches may be used: at low concentration in electrolytes, the Debye-Huckel (DH) theory \cite{kontogeorgisDebyeHuckelTheoryIts2018,silvaDerivationsDebyeHuckel2022,silvaImprovingBornEquation2024} provide a first estimate for the interactions within an ionic liquid. While improvments were proposed over the years to better consider ion-solvent interaction, especially by including dipole-ion \cite{silvaImprovingBornEquation2024} and quadrupole-ion interactions \cite{slavchovQuadrupoleTermsMaxwell2014,slavchovQuadrupoleTermsMaxwell2014a,coxQuadrupolemediatedDielectricResponse2021}, there only have been a few attempts \cite{xiaoReorganizationEnergyElectron2013,xiaoMolecularDebyeHuckelApproach2014} to include the DH theory in the prediction of redox potential (in molten salts). However, at large concentration (such as in ionic liquids), one can expect the formation of ion-pairs \cite{marcusIonPairing2006}. Phenomenological models \cite{krishtalikElectrostaticIonSolvent1991,matsuiDensityFunctionalTheory2013,lundDielectricInterpretationSpecificity2010} (...) Missing:\begin{itemize} @@ -107,6 +107,8 @@ \section{Introduction} \item Motivate the choice of water and acetonitrile and not ionic liquids (\textit{e.g.}, absence of experimental data?). \end{itemize} +In this study, (...) + This paper is organized as follows: Section \ref{sec:theory} introduces key concepts and various simplified models that aid in the interpretation of the results. The methodology employed in this study is detailed in Section \ref{sec:methodo}. The results are then presented in four parts: the impact of substituents on the redox properties is discussed in Section \ref{sec:sar}, followed by an analysis of the effects of solvents in Section \ref{sec:solv}, and the influence of electrolytes in Section \ref{sec:elect}. Finally, a comparison between theoretical predictions and experimental results is provided in Section \ref{sec:exp}. Conclusions and future outlooks are presented in Section \ref{sec:conclusion}. \section{Theory}\label{sec:theory} @@ -189,11 +191,9 @@ \subsection{Redox potentials in solution} \end{equation} to be used in Eq.~\eqref{eq:nernst}. It should provide similar results to the approach developed by Cossi \emph{et al.} in Ref.~\citenum{cossiInitioStudyIonic1998}. -%Note that this model is based on a monopole (ion-charges) interaction: while modifications have been proposed first \cite{krishtalikElectrostaticIonSolvent1991}, extension to further multipoles moments \cite{silvaImprovingBornEquation2024,lahiriDeterminationGibbsEnergies2003,duignanContinuumSolventModel2013}, especially dipole \cite{silvaImprovingBornEquation2024} and quadrupole \cite{slavchovQuadrupoleTermsMaxwell2014,slavchovQuadrupoleTermsMaxwell2014a,coxQuadrupolemediatedDielectricResponse2021}, now exists. They, however, generally focuses on simple ions and not ionic molecules. - \subsection{Model for the impact of the substituent} -In a first approximation, the electrostatic interaction between the substituent(s) and the charge formed upon oxidation or reduction influences the redox potential of nitroxides. Specifically, assuming a non-charged substituent, charge-dipole interactions stabilize the oxammonium ($>$\ce{N+=O}) if the dipole is aligned with the charge, while they destabilize the hydroxylamine ($>$\ce{N-O-}), both resulting in a decrease in the redox potential (see Fig.~\ref{fig:dipole}). Within this framework, it is therefore expected that compounds with donor substituents have lower redox potentials than acceptor substituents. +In a first approximation, the electrostatic interaction between the substituent(s) and the charge formed upon oxidation or reduction influences the redox potential of nitroxides. Specifically, assuming a non-charged substituent, charge-dipole interactions stabilize the oxoammonium ($>$\ce{N+=O}) if the dipole is aligned with the charge, while they destabilize the hydroxylamine ($>$\ce{N-O-}), both resulting in a decrease in the redox potential (see Fig.~\ref{fig:dipole}). Within this framework, it is therefore expected that compounds with donor substituents have lower redox potentials than acceptor substituents. \begin{figure}[!h] @@ -271,7 +271,7 @@ \subsection{Impact of ion-pair formation on redox potentials} \subsection{Model for the ion-pair formation} -Insight into the formation of ion pairs ($K_{01}$ and $K_{21}$ in Fig.~\ref{fig:cip}) is provided by a simple model proposed by Lund et al. \cite{lundDielectricInterpretationSpecificity2010}. It is based on the balance between the solvation of the individual charges (described by the Born model, Eq.~\eqref{eq:born}) and the formation of a dipole when the two charges interact, leading to the famous Onsager model \cite{onsagerElectricMomentsMolecules1936,aubretUnderstandingLocalField2019}. From the thermodynamic cycle given in Fig.~\ref{fig:ionpair}, one can derive the following expression: \begin{equation} +Insight into the formation of ion pairs ($K_{01}$ and $K_{21}$ in Fig.~\ref{fig:cip}) is provided by a simple model proposed by Lund et al. \cite{lundDielectricInterpretationSpecificity2010}. It is based on the balance between the solvation of the individual charges (described by the Born model, Eq.~\eqref{eq:born}) and the formation of a dipole when the two charges interact, leading to the famous Onsager model \cite{onsagerElectricMomentsMolecules1936,krishtalikElectrostaticIonSolvent1991,aubretUnderstandingLocalField2019}. From the thermodynamic cycle given in Fig.~\ref{fig:ionpair}, one can derive the following expression: \begin{equation} \Delta G_{\text{pair}}^\star = \frac{1}{4\pi\varepsilon_0}\,\left\{\left[\frac{q_1^2}{2a_1}+\frac{q_2^2}{2a_2}\right]\,\left[1-\frac{1}{\varepsilon_r}\right]+\frac{q_1\,q_2\,|q_1-q_2|}{2\,\mu}-\frac{\varepsilon_r-1}{2\varepsilon_r+1}\,\frac{\mu^2}{a^3}\right\},\label{eq:pair} \end{equation} where $a_1$, $a_2$, and $a=s_2\,( a_1^3+a_2^3)^{1/3}$ are the radii of the cavities corresponding to $q_1$, $q_2$, and the dipole, respectively, defined as $\mu = \frac{s_1}{2}\,|q_2-q_1|\,(a_1+a_2)$. $s_1$ and $s_2$ are scaling factors, which account for the electrostatic attraction between the two charges forming the dipole ($s_1\leq 1$) and the fact that the cavity might not be spherical ($s_2\geq 1$). @@ -455,7 +455,7 @@ \subsection{Impact of the electrolytes} \label{sec:elect} \end{inparaenum} Using compound \textbf{4} as an example (see Fig.~\ref{fig:pos-anion}), the energy difference between these positions is small (approximately \SI{5}{\kilo\joule\per\mole} for \textbf{12}). The first position is generally favored. In acetonitrile, however, the nitroxide-to-counterion distance is smaller due to the lower dielectric constant, which results in reduced charge screening. Consequently: \begin{inparaenum}[(i)] - \item for the oxammonium ion, the lower charge screening in acetonitrile secludes the \ce{BF4-} from interacting with the substituent in the second position, favoring the first position, and + \item for the oxoammonium ion, the lower charge screening in acetonitrile secludes the \ce{BF4-} from interacting with the substituent in the second position, favoring the first position, and \item for hydroxylamine, both positions result in smaller complexation energies due to the reduced dielectric constant. \end{inparaenum} \todo{What about the other families?} @@ -492,6 +492,7 @@ \subsection{Comparison to experiment} \label{sec:exp} \section{Conclusion} \label{sec:conclusion} Random thoughts:\begin{itemize} + \item more of DH could be included (dipole, quandrupole) \item We only focused on the impact of substituent. Other study do the counterion part. \item The impact remains moderate, but I hope I have provided keys in understanding interaction.\todo{check \cite{zhangInteractionsImidazoliumBasedIonic2016}} \item Ionic liquids needs to be addressed at some point ;)