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Zhang, Chen, Junxia Pi, Shu Chen, Ping Liu, and Peipei Sun. "Construction of a 4H-pyrido[4,3,2-gh]phenanthridin-5(6H)-one skeleton via a catalyst-free radical cascade addition/cyclization using azo compounds as radical sources." Organic Chemistry Frontiers 5, no. 5 (2018): 793–96. http://dx.doi.org/10.1039/c7qo00926g.
The new radical addition/cyano insertion/homolytic aromatic substitution cascade reaction initiated by the thermal homolysis of azo compounds under catalyst-free conditions produced polycyclic phenanthridine derivatives.
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Shin, Jeongcheol, Jiseon Lee, Jong-Min Suh, and Kiyoung Park. "Ligand-field transition-induced C–S bond formation from nickelacycles." Chemical Science 12, no. 48 (2021): 15908–15. http://dx.doi.org/10.1039/d1sc05113j.
d–d excitations can accelerate C–S reductive eliminations of nickelacycles via intersystem crossing to a repulsive 3(C-to-Ni charge transfer) state inducing Ni–C bond homolysis. This homolytic photoreactivity is common for organonickel(ii) complexes.
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Qianzhu, Haocheng, Wenjuan Ji, Xinjian Ji, Leixia Chu, Chuchu Guo, Wei Lu, Wei Ding, Jiangtao Gao, and Qi Zhang. "Reactivity of the nitrogen-centered tryptophanyl radical in the catalysis by the radical SAM enzyme NosL." Chemical Communications 53, no. 2 (2017): 344–47. http://dx.doi.org/10.1039/c6cc08869d.
The nitrogen-centered tryptophanyl radical produced by the radical SAM enzyme NosL can undergo both Cα–Cβ and Cα–C homolytic cleavages, and we show that the Cα–Cβ homolysis is energetically more favorable. The kinetics of NosL catalysis are also reported in this Communication.
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Ishihara, Koji, and Thomas Wilson Swaddle. "The pressure dependence of rates of homolytic fission of metal–ligand bonds in aqueous solution." Canadian Journal of Chemistry 64, no. 11 (November 1, 1986): 2168–70. http://dx.doi.org/10.1139/v86-356.
The volume of activation for the exclusively homolytic decomposition of protonated 4-pyridylmethylchromium(III) ion in aqueous HClO4 at 63.4 °C is +19 cm3 mol−1, with negligible dependence on pressure up to 350 MPa at least. The origins of the strongly positive volumes of activation that characterize homolysis of complex cations in aqueous solution are examined.
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Yorimitsu, Hideki. "Homolytic substitution at phosphorus for C–P bond formation in organic synthesis." Beilstein Journal of Organic Chemistry 9 (June 28, 2013): 1269–77. http://dx.doi.org/10.3762/bjoc.9.143.
Organophosphorus compounds are important in organic chemistry. This review article covers emerging, powerful synthetic approaches to organophosphorus compounds by homolytic substitution at phosphorus with a carbon-centered radical. Phosphination reagents include diphosphines, chalcogenophosphines and stannylphosphines, which bear a weak P–heteroatom bond for homolysis. This article deals with two transformations, radical phosphination by addition across unsaturated C–C bonds and substitution of organic halides.
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Cameron, Dale R., Alison M. P. Borrajo, Gregory R. J. Thatcher, and Brian M. Bennett. "Organic nitrates, thionitrates, peroxynitrites, and nitric oxide: a molecular orbital study of the (X = O, S) rearrangement, a reaction of potential biological significance." Canadian Journal of Chemistry 73, no. 10 (October 1, 1995): 1627–38. http://dx.doi.org/10.1139/v95-202.
The rearrangement of organic thionitrate to sulfenyl nitrite potentially mediates the release of nitric oxide from organic nitrates, such as nitroglycerin, in the presence of thiol. The biological activity of these nitrovasodilators is proposed to result from release of nitric oxide in vivo. The thionitrate rearrangement bears analogy to the rearrangement of peroxynitrous acid to nitric acid, which has been proposed to mediate the biological toxicity of nitric oxide and superoxide. In this paper, the two concerted rearrangement processes and competing homolytic reactions are explored using molecular orbital calculations at levels up to MP4SDQ/6-31G*//MP2/6-31G*. Examination of structure and energy for all conformers and isomers of RSONO2 (R = H, Me), models for organic thionitrates and their isomers, demonstrates that structures corresponding to thionitrates and sulfenyl nitrates are of similar energy. Free energies of reaction for homolysis of these compounds are low (ΔG0 < 19 kcal/mol), whereas the barrier for concerted rearrangement is large (ΔG≠(aq.) = 56 kcal/mol). The larger barrier for concerted rearrangement of peroxynitrous acid to nitric acid (ΔG≠(aq.) = 60 kcal/mol) again compares unfavourably with homolysis (ΔG0 < 11 kcal/mol for homolysis to NO2 or •NO). The transition state structures, confirmed by normal mode and intrinsic reaction coordinate analysis, indicate that considerable structural reorganization is required for concerted rearrangement of the ground state species. These results suggest that concerted rearrangement is not likely to be a viable step in either biological process. However, rearrangement via homolysis and radical recombination may provide an energetically accessible pathway for peroxynitrous acid rearrangement to nitric acid and rearrangement of thionitrate to sulfenyl nitrite. In this case, NO2 will be a primary product of both reactions. Keywords: thionitrate, nitric oxide, peroxynitrite, nitrovasodilator, nitrate.
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Edeleva, Mariya, Gerard Audran, Sylvain Marque, and Elena Bagryanskaya. "Smart Control of Nitroxide-Mediated Polymerization Initiators’ Reactivity by pH, Complexation with Metals, and Chemical Transformations." Materials 12, no. 5 (February 26, 2019): 688. http://dx.doi.org/10.3390/ma12050688.
Because alkoxyamines are employed in a number of important applications, such as nitroxide-mediated polymerization, radical chemistry, redox chemistry, and catalysis, research into their reactivity is especially important. Typically, the rate of alkoxyamine homolysis is strongly dependent on temperature. Nonetheless, thermal regulation of such reactions is not always optimal. This review describes various ways to reversibly change the rate of C–ON bond homolysis of alkoxyamines at constant temperature. The major methods influencing C–ON bond homolysis without alteration of temperature are protonation of functional groups in an alkoxyamine, formation of metal–alkoxyamine complexes, and chemical transformation of alkoxyamines. Depending on the structure of an alkoxyamine, these approaches can have a significant effect on the homolysis rate constant, by a factor of up to 30, and can shorten the half-lifetime from days to seconds. These methods open new prospects for the application of alkoxyamines in biology and increase the safety of (and control over) the nitroxide-mediated polymerization method.
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Shu, Xing-Zhong, and Xiaobo Pang. "Titanium: A Unique Metal for Radical Dehydroxylative Functionalization of Alcohols." Synlett 32, no. 13 (March 4, 2021): 1269–74. http://dx.doi.org/10.1055/a-1406-0484.
AbstractThe dehydroxylative functionalization of alcohols is synthetic appealing, but it remains a long-term challenge in the synthetic community. Low-valent titanium has shown the power to produce carbon radicals from alcohols via homolytic cleavage of the C–OH bonds and thus offers the potential to overcome this problem. In this perspective manuscript, we summarized the recent advance on radical dehydroxylative transformation of alcohols either promoted or catalyzed by titanium. The limitation and outlook of the studies in this field are also provided.1 Introduction2 Recent Developments in Dehydroxylative Functionalization of Alcohols2.1 Stoichiometric Titanium Complexes Mediated Homolysis of Alcohols2.2 Radical Dehydroxylative Functionalization of Alcohols by Ti Catalysis3 Summary and Outlook
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Koppenol, Willem H., and Reinhard Kissner. "Can ONOOH Undergo Homolysis?" Chemical Research in Toxicology 11, no. 2 (February 1998): 87–90. http://dx.doi.org/10.1021/tx970200x.
Marquess, Daniel. "Studies on the insertion-homolysis mechanism for carbon-sulphur bond formation in penicillin biosynthesis." Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306548.
Helling, Christoph [Verfasser], and Stephan [Akademischer Betreuer] Schulz. "Pnictogen–Carbon Bond Homolysis : an approach to the synthesis of group 13 metal-substituted pnictanyl radicals / Christoph Helling ; Betreuer: Stephan Schulz." Duisburg, 2021. http://d-nb.info/123491123X/34.
Havot, Jeffrey. "Synthèse et étude d'alcoxyamines inédites : de la théranostique à l'activation par résonnance plasmonique." Electronic Thesis or Diss., Aix-Marseille, 2022. http://www.theses.fr/2022AIXM0080.
Les alcoxyamines sont des molécules connues pour leur capacité à produire des radicaux via l’homolyse de leur liaison C-ON. Cette homolyse peut être produite par diverses méthodes d’activation, comme par voie thermique, photocatalysée ou encore enzymatique. De plus, il est possible de modifier leur structure de manière exhaustive, afin d’en modifier les propriétés. Toutes ces possibilités permettent d’envisager pour cette famille de composés de nombreuses applications dans des domaines extrêmement variés. Cette thèse présente la synthèse et l’étude physico-chimique d’un certain nombre d’alcoxyamines inédites. Ces dernières ont été développées dans l’objectif d’une meilleure compréhension de leurs modes d’action et d’une amélioration des propriétés recherchées vis-à-vis d’applications innovantes comme la théranostique ou encore des moyens d’activation plus exotiques comme la résonnance plasmonique Alkoxyamines are molecules well-known for their abilities to generate radicals from C-ON bond homolysis. This homolysis can be induced by various methods like thermally, by photocatalysis or by enzymatic activation. In addition, it is easy to modulate their chemical properties by modifying their structure. Thus we can imagine many various applications for these compounds. Here we will describe the synthesis of new alkoxyamines and investigations about their properties. These alkoxyamines have ben developed in order to acquire new knowledge about their reactivity, but also to improve their structures with respect to innovative applications like theranostic, or some new homolysis pathways like localized plasmon resonance
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Robertson, Jeremy. "Ring expansion reaction via homolytic pathways." Thesis, University of Oxford, 1990. http://ora.ox.ac.uk/objects/uuid:194ca194-4848-470b-a21f-c16869257b96.
The preparation of carbocyclic medium rings by two electron processes is reviewed with particular reference to the synthesis of natural products. The formation of medium rings by oxidative and homolytic methods is also reviewed. The synthesis and behaviour of both cis- and tran- ring expansion precursors is described. The 1,4-addition of tributylstannyl lithium to a range of cyclic α,β-unsaturated ketones was performed and procedures found whereby the so-formed enolates could be alkylated with a variety of electrophiles. Using these procedures a range of trans- ring expansion precursors were obtained in moderate to good yield. By the 1,4-addition of tributylstannyl lithium to 2-(ω-phenylselenoalkyl)-cyclohexenones, followed by enolate quenching with either water or methyl iodide, a range of cis- ring expansion precursors were produced. Homolytic ring expansion by either one, three, or four carbon atoms was shown to be possible, producing, respectively, seven, nine, or ten membered functionalised cycloalkenones in high yield except in cases where intramolecular reductive elimination was also possible. Attempts to extend this methodology to the synthesis of exomethylene cycloalkanones is described. The 3-tributylstannyl-3-(ω-phenylselenoalkyl)-cyclohex-2-enone precursors were found not to be successful substrates for ring expansion. The regiospecific alkylation of 2-(tributylstannylmethyl)-cyclohexanone with l-chloro-4-iodo-butane, followed by conversion of the chloride moiety to iodide led to a precursor which, on exposure to homolysis conditions, fragmented to produce the desired exomethylene cyclodecanone in high yield. Work directed towards the synthesis of medium ring cycloalkynones is described. Procedures were developed whereby 2-alkylated cyclohexan-l,3-dione derivatives could be obtained cleanly and in excellent yield on a large scale. The conversion of these derivatives to potential cycloalkynone precursors is described. It is shown that the products obtained after exposure of these precursors to homolysis conditions could, in principle, be derived from the putative cycloalkynones and mechanisms are suggested to explain the formation of these compounds. The homolytic ring expansion reaction was also performed on a substrate possessing an acyl radical precursor in the hope that a medium ring 1,2-dione would be produced. The synthesis of this substrate and its behaviour towards ring expansion is described. It is shown that, again, radical reaction was successful (to the medium ring dione) however subsequent reactions of this product led to the isolation and characterisation of a number of compounds . Attempts to extend this methodology to the synthesis of the natural products curdione and neocurdione is also described. Model reactions with 2,6-dimethylcyclohex-2-enone as the 1,4-addition precursor and 1,4-di-iodobutane as the electrophile led to a ring expansion substrate which fragmented to two ring contracted isomeric compounds in addition to the ring expanded material. Approaches to the preparation of suitable electrophiles for the natural product synthesis are described and their proposed use in subsequent conversion to curdione and neocurdione given.
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Spratley, A. "Some studies of the homolytic reactions of chlorinated benzenes." Thesis, City University London, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355587.
Norberg, Daniel. "Quantum Chemical Studies of Radical Cation Rearrangement, Radical Carbonylation, and Homolytic Substitution Reactions." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8178.
Carré, Christiane. "Étude des réactions photoinduites de l'octahydro-1,2,3,4,6,7,8,9 phénazine en solution ou la voie des diazines vers la photo-homolyse de l'eau." Paris 11, 1985. http://www.theses.fr/1985PA112084.
Certaines diazines-1,4 - en particulier la phénazine – sont susceptibles de provoquer la photo-homolyse de l’eau. Ce travail porte sur les réactions photoinduites de l’octahydro-1,2,3,4,6,7,8,9 phénazine. Après étude par R. P. E. Des diverses espèces radicalaires formées par transfert d’un électron sur cette molécule, nous avons pu montrer que par irradiation des solutions d’octahydrophénazine dans l’eau ou dans l’alcool, c’est le radical cation qui se forme très rapidement : il résulte de l’arrachement d’un atome d’hydrogène par la molécule monoprotonée excitée. C’est surtout l’octahydrophénazine qui fournir cet atome d’hydrogène en milieu aqueux, tandis qu’en milieu alcoolique, c’est le solvant qui est le principal donneur. Le radical résultant de la perte d’un atome d’hydrogène par la molécule de départ redonne principalement le produit initial en arrachant un atome d’hydrogène au solvant, ce qui conduit à la formation d’eau oxygénée ou d’une cétone. Il peut également donner des produits d’addition ou évoluer vers la tétrahydro-1,2,3,4 phénazine. Le mécanisme proposé met en évidence le rôle particulier joué par les hydrogènes cyclohexaniques en α du noyau pyrazinique de la molécule.
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Ni, Liming. "Synthesis and evaluation of new peptidyl phosphonate analogs of benzamidine, lysine and homolysine as irreversible inhibitors for thrombin and other trypsin-like enzymes." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/27080.
Lingua, Hugo. "SH2 sur les dialkylzincs par les radicaux α-alcoxycarbonyle, carbozincations et additions radicalaires impliquant des ynamides : approches expérimentales et théoriques." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0564.
La réactivité de l’α-bromoacrylate d’éthyle et du benzylidène malonate d’éthyle vis à vis des dialkylzincs en milieu aérobie a été étudiée afin d’évaluer la capacité des radicaux α-alcoxycarbonyle tertiaires à évoluer par SH2 sur le métal pour conduire à un énolate de zinc. Le travail expérimental réalisé à partir de l’α-bromoacrylate d’éthyle a permis la synthèse de cyclopropanes et de céto-esters. Dans le cas des benzylidène malonates la réversibilité de l’addition du diéthylzinc sur le substrat, a été mise en évidence. L’effet inhibiteur d’additifs tels que TMSCl ou CuCl concourt à indiquer que les peroxydes de zinc formés dans le milieu pourraient y tenir un rôle clé. L’étude théorique a mis en évidence pour les 2 substrats étudiés, le rôle crucial de la stabilisation de l’énolate formé sous la forme d’un chélate à 5 ou 6 chaînons. Les carbozincations d’ynamides via le CuI ou le FeCl2 en présence de dialkylzincs ont été étudiées pour la synthèse régio-et stéréosélective d'énamides tri- ou tétrasubstitués. Le CuI s’est montré plus performant et moins substrat-dépendant que FeCl2. Une étude théorique a été réalisée afin de mieux comprendre ce phénomène. Enfin, l'addition intermoléculaire des radicaux sulfanyle sur les ynamides a été revisitée. Les calculs théoriques et les résultats expérimentaux montrent que la régio- et stéréosélectivité de la réaction dépendent de la nature du substituant porté par le carbone en β de l’atome d’azote et des conditions expérimentales. L’addition intermoléculaire inédite d’un radical carboné électrophile sur ces substrats a pu être décrite et ouvre de nouvelles perspectives quant à la synthèse d’énamides tétrasubstitués originaux The reactivity of ethyl α-bromoacrylate and ethyl benzylidene malonate towards dialkylzincs in aerobic medium was studied in order to evaluate the capacity of tertiary α-alcoxycarbonyl radicals to undergo SH2 at zinc leading to a zinc enolate. The use of ethyl α-bromoacrylate allowed the synthesis of cyclopropanes and keto-esters. With the second substrate, the addition of the alkyl group was shown to be reversible. The inhibitor effect of additives like TMSCl or CuCl suggested that zinc peroxydes formed in situ could play a key role in the process. Theoretical studies highlighted the crucial role of the stabilization of the zinc enolate through the formation of a 5 or 6-membered chelate. Regio- and stereoselective synthesis of tri- and tetra-substituted enamides was achieved through the carbozincation of ynamides in the presence of dialkylzincs and CuI or FeCl2 as catalyst. CuI was shown to be more efficient and less substrate-dependent than FeCl2. Molecular modelings were performed to better understand this phenomen. Finally, intermolecular addition of sulfanyl radicals onto ynamides was revisited. Theoretical calculations and experimental results showed that the regio- and stereo-selectivity of the process depended on the nature of the substituent on the carbon in β position of the nitrogen atom and on experimental conditions. Unprecedented intermolecular addition of a carbon-centered radical has been described and opened new perspectives for the synthesis of original tetrasubstituted enamides
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Vallet, Anne-Laure. "Réactivités de NHC-Boranes Soufrés." Thesis, Paris 11, 2014. http://www.theses.fr/2014PA112261.
Avec le développement des concepts de la chimie verte, il est devenu nécessaire de remplacer les métaux toxiques par des composés plus respectueux de l’environnement. Donneurs d’hydrogène pour des réactions radicalaires, les hydrures de trialkylétain sont encore très utilisés. Les NHC-boranes se sont révélés de bons remplaçants pour les réactions de désoxygénation. Cependant, les réactions de déshalogénation effectuées avec des NHC-boranes sont moins efficaces et il a fallu avoir recours au concept de catalyse à polarité inversée. Ces travaux ont été le point de départ de cette thèse où la synthèse de nouveaux NHC-boranes possédant une liaison B-S ou B-N est développée. L’étude des propriétés de ces nouveaux complexes a été effectuée et des applications en chimie organique et en science des polymères ont été trouvées. Par ailleurs, en vue d’étudier les effets polaires sur la formation et la réactivité des radicaux boryles, une nouvelle famille de carbène-boranes a été synthétisée Along with the development of green chemistry, it became necessary to avoid toxic metallic complexes in organic reactions and replace them by more sustainable compounds. An hydrogen donors for radical reactions, trialkylstannanes are still widely used. NHC-boranes seem to be good substitutes for deoxygenation reactions. However, dehalogenation reactions are less effective and polar reversal catalysis was used. This work was the starting point of this Ph.D thesis where the synthesis of new NHC-boranes bearing a B-S or B-N bound is developed. The study of the properties of these new complexes was performed and applications in organic chemistry as well as in polymer science were found. Besides, to study polar effects on the formation and on the reactivity of boryl radicals, a new family of carbene-boranes was synthesized
(Editor), Gennadii Efremovich Zaikov, Yu B. Monakov (Editor), Alfonso Jimenez (Editor), and Iu B. Monakov (Editor), eds. Homolytic and Heterolytic Reactions: Problems and Solutions. Nova Science Publishers, 2004.
Williams, G. H., D. H. R. Barton, and W. Doering. Homolytic Aromatic Substitution: International Series of Monographs on Organic Chemistry. Elsevier Science & Technology Books, 2014.
Cleaves II, Henderson James. "Homolysis." In Encyclopedia of Astrobiology, 1. Berlin, Heidelberg: Springer Berlin Heidelberg, 2022. http://dx.doi.org/10.1007/978-3-642-27833-4_733-4.
Cleaves II, Henderson James. "Homolysis." In Encyclopedia of Astrobiology, 1343–44. Berlin, Heidelberg: Springer Berlin Heidelberg, 2023. http://dx.doi.org/10.1007/978-3-662-65093-6_733.
Antal, Michael Jerry, Andrew Brittain, Carlos DeAlmeida, Sundaresh Ramayya, and Jiben C. Roy. "Heterolysis and Homolysis in Supercritical Water." In ACS Symposium Series, 77–86. Was,hington, DC: American Chemical Society, 1987. http://dx.doi.org/10.1021/bk-1987-0329.ch007.
Stein, Stephen E., and Mahendra M. Suryan. "Homolysis of Substituted Anisoles: Substituent Effects on Phenoxyl Radical Stabilities." In Oxygen Radicals in Biology and Medicine, 105–14. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4684-5568-7_15.
Fink, Richard G. "Coenzyme B12-Based Chemical Precedent for Co-C Bond Homolysis and Other Key Elementary Steps." In Vitamin B12and B12-Proteins, 383–402. Weinheim, Germany: Wiley-VCH Verlag GmbH, 2007. http://dx.doi.org/10.1002/9783527612192.ch25.
Rossi, Roberto A., María E. Budén, and Javier F. Guastavino. "Homolytic Aromatic Substitution." In Arene Chemistry, 219–42. Hoboken, NJ: John Wiley & Sons, Inc, 2015. http://dx.doi.org/10.1002/9781118754887.ch9.
Tumanov, Vladimir Evgen'vich, and Andrei Ivanovich Prokhorov. "Web database on bond dissociation energies of organic compounds." In 23rd Scientific Conference “Scientific Services & Internet – 2021”. Keldysh Institute of Applied Mathematics, 2021. http://dx.doi.org/10.20948/abrau-2021-21.
The article presents a scientific service on the Internet "Bond Dissociation Energies of Organic Compounds Database". This web database contains experimental values of dissociation energies of homolytic bonds. The service is intended for use by a wide range of chemists, theorists and practitioners in the open access on the Internet. The paper provides a brief overview of the literature sources of the dissociation energies of bonds of organic molecules, which are calculated theoretically, measured experimentally and estimated from kinetic and thermochemical experimental data. Descriptions of experimental data sources, classes of organic compounds and calculation methods are given. The logical structure of the database and the description of the main fields of its tables are given. The architecture of the web database is presented. The main search form of the database interface is presented and examples of search results for a specific organic compound and a fragment of a chemical formula are given. For most compounds, the values of the bond dissociation energy are given at a temperature of 298.15 K, which is usually absent in most sources (taking into account temperature correlations). Currently, work is underway to analyze the published data taking into account the entropy effects.
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Jeremić, Svetlana R., Jelena R. Đorović Jovanović, Marijana S. Stanojević Pirković, and Zoran S. Marković. "THERMODYNAMICALLY INVESTIGATIONS OF FREE RADICAL SCAVENGER POTENCY OF 1,2,4-TRIHYDROXYTHIOXANTHONE." In 1st INTERNATIONAL Conference on Chemo and BioInformatics. Institute for Information Technologies, University of Kragujevac, 2021. http://dx.doi.org/10.46793/iccbi21.414j.
The operative mechanism of the antioxidative action of 1,2,4-trihydroxythioxanthone (TX) is investigated in this contribution. Conclusions are made based on enthalpy values, as thermodynamical parameters. All calculations are done using the M06-2X/6-311++G(d,p) level of theory. To imitate polar and non-polar environments, calculations are done in water and benzene as the medium. It is found that, among three possible radicals that TX can generate, the most stable is the one obtained by homolytic cleavage of the O-H group in position 4. It was found that HAT (Hydrogen Atom Transfer) is the most plausible mechanism for that purpose in benzene. On the other hand, the most favorable mechanism in water is SPLET (Sequential Proton Loss Electron Transfer). Here is estimated the capacity of TX to deactivate hydroxyl (HO●), hydroperoxyl (HOO●) and methylperoxyl radical (CH3OO●). It is found that TX can deactivate all three free radicals following HAT and SPLET reaction mechanisms competitively, in the polar and non-polar environment. SET-PT (Single-Electron Transfer followed by Proton Transfer) is the inoperative mechanism for radicals scavenging, in the polar and non-polar environment.
Reports on the topic "Homolysis":
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Lee, Shaoyung. Kinetic study of the reaction of ferrocenes and ferrocenium ions with ground and excited states of tris(2,2-bipyridine)chromium ions and the preparation and homolysis of organocobalt complexes. Office of Scientific and Technical Information (OSTI), January 1990. http://dx.doi.org/10.2172/6835414.
Heinekey, D. M. Homolytic activation of hydrocarbons and hydrogen by persistent metal radicals. Office of Scientific and Technical Information (OSTI), January 1992. http://dx.doi.org/10.2172/6716196.
Heinekey, D. M. Homolytic activation of hydrocarbons and hydrogen by persistent metal radicals. Progress report, January 1, 1992--November 1, 1992. Office of Scientific and Technical Information (OSTI), December 1992. http://dx.doi.org/10.2172/10136755.
[Homolytic activation of hydrocarbons and hydrogen by persistent radicals]. Office of Scientific and Technical Information (OSTI), January 1993. http://dx.doi.org/10.2172/6837370.
[Homolytic activation of hydrocarbons and hydrogen by persistent radicals]. Final report. Office of Scientific and Technical Information (OSTI), February 1993. http://dx.doi.org/10.2172/10122867.
