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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Métallation et substitution nucléophile aromatique des acides benzoïques non protégés : application à la synthèse totale de l'apogossypol

Le, Tin Thanh 16 December 2011 (has links) (PDF)
Dans le cadre d'un projet général concernant l'étude de la réactivité des acidesbenzoïques non protégés avec les organométalliques, la synthèse totale d'analoguesstructuraux de l'apogossypol mettant en jeu des réactions de métallation aromatique a étéétudiée ainsi que la réaction de substitution nucléophile aromatique des acides benzoïquesortho-fluorés et ortho-méthoxylés.Le gossypol, (1,1',6,6',7,7'-hexahydroxy-5,5'-di-iso-propyl-3,3'-diméthyl-2,2'-binaphtalène-8,8'-dicarboxaldéhyde), pigment principal des graines du cotonnier, existe sousla forme de deux atropoisomères et possède de multiples applications pharmaceutiques. Il estnotamment un inhibiteur efficace des protéines anti-apoptotiques de la famille Bcl-2. Legossypol déformylé ou apogossypol présente des propriétés similaires mais est plus stable,plus sélectif et moins toxique. Une méthode permettant de remplacer les groupes iso-propylesdu gossypol par des groupes structurellement proches a été mise au point. La stratégie retenuemet à profit les compétences du laboratoire dans le domaine des réactions de métallation etrepose sur la lithiation latérale de l'acide 4-hydroxy-6,7-diméthoxy-8-méthyl-2-naphtoïquepar le tétraméthylpipéridure de lithium. Divers dérivés 5,5'-didés-iso-propyl-5,5'-dialkylapogossypol racémiques ont été préparés selon cette méthode. La synthèse asymétriqued'analogues de l'apogossypol a également été étudiée et la voie de synthèse sélectionnéerepose sur le " concept lactone ". Un intermédiaire avancé de la synthèse, une lactonefonctionnalisée potentiellement réductible de façon asymétrique, a été préparée.La deuxième partie est consacrée à l'étude de la réaction de substitution nucléophilearomatique des acides benzoïques ortho-fluorés et ortho-méthoxylés (réaction SNArAB). Unerevue de la littérature des réactions de substitution nucléophile aromatique activée par lesesters est présentée. L'influence de substituants méthoxylés et halogénés (F, Cl, Br) sur lasélectivité SNAr/addition 1,2 a été évaluée. Il est montré que les acides 2-fluoro-6-halogénobenzoïques conduisent, par réaction avec les aryllithiens et les arylmagnésiens, auxproduits d'ipso-C2-substitution avec un excellent rendement et la réaction SNArAB permet unaccès efficace aux acides 3-halogéno-[1,1'-biphényl]-2-carboxyliques. Dans le cas de l'acide2,3-diméthoxybenzoïque, il a été découvert que la présence d'un substituant méthoxy enposition 3 permet de limiter la formation de cétone et le produit d'ipso-substitution est isoléavec un rendement correct.
12

Azacalixphyrines : émergence d'une nouvelle famille de tétraazamacrocycles aromatiques / Azacalixphyrins : emergence of a new family of aromatic tetraazamacrocycles

Chen, Zhongrui 19 November 2015 (has links)
Les travaux de thèse présentés dans ce mémoire ont ciblé trois familles de molécules π-conjuguées et s’inscrivent plus particulièrement dans le développement de la chimie des amino-azacalixarènes et des dérivés de phénazine, et d’une nouvelle classe de tétraazamacrocycles aromatiques appelés « azacalixphyrine ». Ces composés étant émergents dans la littérature, nous avons volontairement porté nos efforts sur la synthèse et la compréhension de ces nouveaux systèmes π-conjugués afin d’élaborer de nouvelles voies de synthèse mais aussi, le cas échéant, d’établir des relations structure / propriétés. L’accès synthétique à ces composés est basé sur des réactions de substitutions nucléophiles aromatiques. De nouveaux outils moléculaires sont ainsi proposés pour différentes applications dans le domaine de l’énergie, des matériaux et/ou de la santé. / The thesis work deals with three families of π-conjugated molecules and particularly focuses on amino-azacalixarenes and phenazine derivatives as well as a new class of aromatic tetraazamacrocycles named “azacalixphyrin”. Since these compounds are emerging in the literature, we have deliberately focused our efforts on their synthesis and on the physico-chemical studies of these new π-conjugated systems in order to, when it is appropriate, establish structure / properties relationships. The synthetic accesses to these compounds are mainly based on aromatic nucleophilic substitutions. All these derivatives are potentially new molecular tools for various applications in the fields of energy, materials and medicines.
13

Pharmacochimie antiprotozoaire en séries quinazoline et quinoléine : synthèse, évaluation biologique et recherchedu mécanisme d'action. / ANTIPROZOAL PHARMACOCHEMISTRY IN QUINAZOLINE AND QUINOLINE SERIES : SYNTHESIS, BIOLOGICAL EVALUATION AND RESEARCH FOR THE MECHANISM OF ACTION

Kieffer, Charline 11 December 2014 (has links)
Le paludisme et la leishmaniose sont les deux plus importantes infections parasitaires au monde, en termes de mortalité. La recherche de nouvelles molécules actives contre les protozoaires responsables de ces « maladies tropicales négligées », Plasmodium sp et Leishmania sp, est un enjeu majeur de santé publique. Après une première partie dressant un état des lieux des connaissances disponibles en matière de chimiothérapie antiplasmodiale, une seconde partie s’est intéressée à l’étude des propriétés anti-infectieuses du noyau 2-trichlorométhyl-quinazoline, en introduisant en position 4 des motifs alcynyles par couplage de Sonogashira, optimisés par LC/MS. Une troisième partie a porté sur la pharmacomodulation en positions 2 et 4 du même noyau, notamment par réactions de SNAr. Une quatrième partie a consisté à rechercher le mécanisme d'action des meilleures quinazolines antiplasmodiales, via une approche de chromatographie d'affinité sur inhibiteur immobilisé. La fonctionnalisation multi-étapes des molécules les plus puissantes, par un bras espaceur, a été suivie de leur ancrage sur divers supports solides, pour constituer des matrices biocompatibles spécifiques. L’une d’entre-elles a permis la mise en évidence de 2 cibles plasmodiales protéiques originales : la GTPase Pfrab6 et la pyruvate-kinase PfpyrK1. Enfin, une cinquième partie relate la pharmacomodulation antileishmanienne du noyau 8-nitroquinoléin-2(1H)-one. Les travaux se sont intéressés à l'étude de la substitution de la position 4 de ce noyau par des réactions de SNAr, ainsi que des réactions de couplages pallado-catalysés optimisées à l’aide de la technologie micro-ondes. / Malaria and leishmaniasis are the two most important parasitic infections worldwide, in terms of mortality. Thus, the research for new molecules targeting the protozoa parasites responsible for these “neglected tropical diseases”, Plasmodium sp and Leishmania sp, constitute a major challenge in public health. Our work focused first on a current state of knowledge about antiplasmodial chemotherapy. In a view to develop the study of the anti-infective properties of the 2-trichloromethylquinazoline scaffold, a second part presented antiplasmodial pharmacomodulation at position 4 using Sonogashira cross-coupling reaction, optimized with the LC/MS technology. A third part concerned other pharmacomodulation reactions, especially at positions 2 and 4, using especially SNAR reactions. A fourth part consisted in the research of the mechanism of action of the best antiplasmodial quinazolines by using the affinity chromatography on immobilized inhibitor approach. The multi-step functionalization of the most potent derivatives by a spacer side chain was followed by their anchoring onto various solid supports, so as to generate different biocompatible specific matrices. One of them, put in contact with a parasitic lysate, allowed the identification of two original plasmodial targets: the GTPase Pfrab6 and the pyruvate-kinase PfpyrK1. Finally, a fifth part presented the antileishmanial pharmacomodulation of the 8-nitroquinolin-2(1H)-one scaffold, especially at position 4 of the quinoline ring, involving SNAr reactions (with amines, phenols or thiophenols) or pallado-catalyzed coupling reactions (in particular Suzuki-Miyaura), some of them being optimized under microwave irradiation.
14

Synthesis of β-turn and pyridine based peptidomimetics

Blomberg, David January 2007 (has links)
Despite the unfavorable pharmacokinetic properties associated with peptides, they are still of great interest in drug development due to a multitude of interesting biological functions. The development of peptidomimetics strives to maintain or improve the biological activity of a peptide concurrently with removing the unwanted properties. This thesis describes two synthetic approaches to peptidomimetics with particular emphasis on secondary structure mimetics. First the design, synthesis and evaluation of two beta-turn mimetics incorporated in the endorphin Leu-enkephalin is presented. The beta-turn mimetics were stabilized by replacement of the intramolecular hydrogen bond with an ethylene bridge, and the amide bond between Tyr and Gly was replaced with an ether linkage. Linear analogues of the two mimetics were also synthesized. The peptidomimetics and their linear analogues were evaluated in a competitive binding assay at two opiate receptors, my and delta. One of the cyclized beta-turn mimetics was found to be a delta receptor antagonist with an IC50 value of 160 nM. Second a synthetic strategy to a beta-strand mimetic using 2-fluoro-4-iodopyridine as scaffold is described. The synthesis involved a Grignard exchange reaction on the pyridine scaffold using an amino acid derivative as electrophile followed by an SNAr reaction using an amine as nucleophile. The synthesis of a tripeptidomimetic of Leu-Gly-Gly and attempts to introduce chiral building blocks at the C-terminal, as well as studies towards elongated mimetics are presented. Two additional studies deal with the synthesis of two classes of potential thrombin inhibitors based on the pyridine scaffold. The first class contain pyridine as central fragment (P2 residue) substituted with a para-amidinobenzylamine group as P1 residue and various benzoyl groups as P3 residues. Three potential thrombin inhibitors were synthesized and found to be microM inhibitors in an enzymatic assay. In the second class, the pyridine ring serves as P3 residue. This class also lacks a strongly basic group in the P1 position. A small library of eight compounds were synthesized and evaluated in the enzymatic assay. Unfortunately, these compounds lacked inhibitory activity.
15

Síntese e caracterização de amino ácidos e ésteres n-(aminoalquil)-lactâmicos derivados do paba com potencial atividade biológica /

Gonçalves, Renato Sonchini. January 2010 (has links)
Orientador: Eduardo René Pérez Gonzáles / Banca: Alvicler Magalhães / Banca: Wanda Pereira Almeida / O Programa de Pós-Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi da Unesp / Resumo: Amino ésteres lactâmicos derivados do PABA e que podem ser potencialmente bioativos, por exemplo, como anestésicos locais, foram sintetizados com bons rendimentos por uma reação seletiva de SnAr de ácidos benzóicos com n-(3-aminopropil)-lactamas seguida por esterificação com aminoálcoois terciários. Produtos da N-arilação do N, N-dimetilformamida foram também obtidos através da esterificação direta do ácido 4-cloro-3-nitrobenzóico / Abstract: Lactamic amino esters PABA-related, and can potentially bioactive, for exemple, as local anesthetics were synthesized in good yields by a selective 'S IND. n'Ar reactions of benzoic acids with N-(3-aminopropyl)lactams followed by esteterification with tertiary aminoalcohols. Products of the N-arylation with N,N-dimethylformamide are also obtained through of direct esterification of 4-chloro3-nitrobenzoic acid / Mestre
16

The Kinetics and Mechanisms of Some Fundamental Organic Reactions of Nitro Compounds

Li, Zhao 01 May 2012 (has links)
The central topic of this dissertation is to seek the answer to the question: Is the single transition state model appropriate for (1) the proton transfer reactions of nitroalkanes and (2) the aromatic nucleophilic reactions of trinitroarenes? If not, what are the real mechanisms? This objective has been accomplished by careful kinetic and mechanistic studies which take advantage of modern digital acquisition of absorbance - time data, combined with extensive new data analysis of results from pseudo-first-order kinetic measurements. Several new analysis procedures for pseudo-first-order kinetics that are capable of distinguishing between single-step and multi-step mechanisms have been introduced and intensively confirmed during the application in the kinetic study of the target reactions. The procedures include (1) half-life dependence of apparent rate constant, (2) sequential linear pseudo-first-order correlation, (3) approximate instantaneous rate constant analysis, and (4) time-dependent apparent kinetic isotope effects. Various conventional and nonconventional pseudo-first-order kinetic analyses of the reactions of nitroalkanes in aqueous solutions revealed that the reactions are complex and involve kinetically significant intermediates. The spectral evidence for the formation of reactive intermediates was obtained by carrying out the kinetic experiments at the isosbestic points where changes in reactant and product absorbance cancel. The apparent deuterium kinetic isotope effects studies indicated that the deuterium kinetic isotope effects are not associated with the formation of the intermediates. The observations of anomalous Brønsted exponents previously found for this reaction series could be rationalized well with the complex mechanisms proposed in this work, which indicate that the nitroalkane anomaly does not exist, but arises from an interpretation based upon the incorrect assumption that the reactions follow a simple one-step mechanism. Simulations revealed that the generally accepted competitive mechanism was not appropriate to describe the Meisenheimer complex formation during the reaction of 2,4,6-trinitroanisole with methoxide ion in methanol. This conclusion is supported by the conventional pseudo-first-order kinetic analysis. A reversible consecutive mechanism that accounts for the kinetic behavior has been proposed, which involves an intermediate dianion complex that is formed reversibly from the initial 1,3-σ-complex, and then eliminates methoxide ion to form the 1,1-σ-complex product.
17

Métallation et substitution nucléophile aromatique des acides benzoïques non protégés : application à la synthèse totale de l’apogossypol / Metallation and nucleophilic aromatic substitution of unprotected benzoic acids : application to synthesis of apogossypol

Le, Tin Thanh 16 December 2011 (has links)
Dans le cadre d’un projet général concernant l’étude de la réactivité des acidesbenzoïques non protégés avec les organométalliques, la synthèse totale d’analoguesstructuraux de l’apogossypol mettant en jeu des réactions de métallation aromatique a étéétudiée ainsi que la réaction de substitution nucléophile aromatique des acides benzoïquesortho-fluorés et ortho-méthoxylés.Le gossypol, (1,1’,6,6’,7,7’-hexahydroxy-5,5’-di-iso-propyl-3,3’-diméthyl-2,2’-binaphtalène-8,8’-dicarboxaldéhyde), pigment principal des graines du cotonnier, existe sousla forme de deux atropoisomères et possède de multiples applications pharmaceutiques. Il estnotamment un inhibiteur efficace des protéines anti-apoptotiques de la famille Bcl-2. Legossypol déformylé ou apogossypol présente des propriétés similaires mais est plus stable,plus sélectif et moins toxique. Une méthode permettant de remplacer les groupes iso-propylesdu gossypol par des groupes structurellement proches a été mise au point. La stratégie retenuemet à profit les compétences du laboratoire dans le domaine des réactions de métallation etrepose sur la lithiation latérale de l’acide 4-hydroxy-6,7-diméthoxy-8-méthyl-2-naphtoïquepar le tétraméthylpipéridure de lithium. Divers dérivés 5,5’-didés-iso-propyl-5,5’-dialkylapogossypol racémiques ont été préparés selon cette méthode. La synthèse asymétriqued’analogues de l’apogossypol a également été étudiée et la voie de synthèse sélectionnéerepose sur le « concept lactone ». Un intermédiaire avancé de la synthèse, une lactonefonctionnalisée potentiellement réductible de façon asymétrique, a été préparée.La deuxième partie est consacrée à l’étude de la réaction de substitution nucléophilearomatique des acides benzoïques ortho-fluorés et ortho-méthoxylés (réaction SNArAB). Unerevue de la littérature des réactions de substitution nucléophile aromatique activée par lesesters est présentée. L’influence de substituants méthoxylés et halogénés (F, Cl, Br) sur lasélectivité SNAr/addition 1,2 a été évaluée. Il est montré que les acides 2-fluoro-6-halogénobenzoïques conduisent, par réaction avec les aryllithiens et les arylmagnésiens, auxproduits d’ipso-C2-substitution avec un excellent rendement et la réaction SNArAB permet unaccès efficace aux acides 3-halogéno-[1,1’-biphényl]-2-carboxyliques. Dans le cas de l’acide2,3-diméthoxybenzoïque, il a été découvert que la présence d’un substituant méthoxy enposition 3 permet de limiter la formation de cétone et le produit d’ipso-substitution est isoléavec un rendement correct. / As part of a program directed toward the study of the reactivity of unprotected benzoicacids with polar organometallics, the total racemic synthesis of apogossypol analogues bymetalation reactions was studied as well as the aromatic nucleophilic substitution reaction ofortho-fluoro- and ortho-methoxybenzoic acids (SNArAB reaction).Gossypol (1,1’,6,6’,7,7’-hexahydroxy-5,5’-di-iso-propyl-3,3’-diméthyl-2,2’-binaphtalène-8,8’-dicarboxaldéhyde) which is the main pigment of cotton seed, displaysmultiple pharmacological applications. It is a potent anti-apoptotic Bcl-2 protein inhibitor.The racemic route developed herein allows the replacement of the iso-propyl groups byvirtually any alkyl groups, providing a series of 5,5’-dides-iso-propyl-5,5’-dialkylapogossypolderivatives. Lateral metalation of 4-hydroxy-6,7-dimethoxy-8-methyl-2-naphthoic acid withLTMP is the key step of the synthesis. Atroposelective synthesis of apogossypol analoguewas also examined. The strategy relies on the “lactone concept” and involves a functionalizedlactone as a key intermediateThe influence of halogen atoms (F, Cl, Br) and methoxy groups on the 1,2-addition/SNArAB selectivity was examined. Treatment of 2-fluoro-6-halobenzoic acids withorganolithiums or Grignard reagents gives ipso-substituted products in excellent yields. Themethod allows the efficient preparation of 3-halo-[1,1’-biphenyl]-2-carboxylic acids and doesnot require protection of the carboxylate. Interestingly, the presence of an additional methoxyin C3 reduces the nucleophilic addition of the organometallic species to the carboxylate and2,3-dimethoxybenzoic acid affords ipso-substituted products in good yields.
18

Synthèse, pharmacomodulation et évaluation biologique de nouveaux dérivés de quinazoline à visées antiparasitaire et anticancéreuse / Synthesis, pharmacomodulation and biological evaluation of new quinazoline derivatives as potential antiparasitic and anticancer agents

Kabri, Youssef 12 March 2010 (has links)
Ce travail est consacré à la synthèse, pharmacomodulation et évaluation de nouveaux dérivés de quinazoline à visées antiparasitaire et anticancéreuse sous irradiation micro-ondes. Dans un premier chapitre, nous indiquons les principales méthodes d’accès au noyau quinazoline, les propriétés pharmacologiques associées aux principes actifs comportant ce motif et nous présentons les données bibliographiques actualisées sur la réaction de SRN1. Lors du second chapitre, la synthèse et la réactivité avec les anions nitronates et sulfinates de la 2-chlorométhyl-3-méthylquinazolin-4(3H)-one sont successivement décrites. Une étude mécanistique permet de démontrer le mécanisme radicalaire en chaîne SRN1 concernant la réaction avec les anions nitronates et un mécanisme de type SN2 avec les anions sulfinates. Par la suite, nous nous sommes intéressés à la préparation de nouvelles quinazolines, sous irradiation micro-ondes, en étudiant les réactions de SNAr puis de couplage de Suzuki-Miyaura en série 4-chloroquinazoline. A partir de ces résultats, nous avons développé la réaction régiosélective de Suzuki-Miyaura, sur la 4,7-dichloro-2-(2-méthylprop-1-ényl)-6-nitroquinazoline, et préparé toute une série de 4,7-diarylquinazolines hautement fonctionnalisées. Enfin, l’évaluation biologique des produits issus des réactions de SNAr a révélé des activités antipaludiques, anti-Leishmania et inhibitrices d’EGFR1 prometteuses, détaillées dans le dernier chapitre. / This work focuses on the synthesis of new bioactive quinazoline derivatives under microwave irradiation. In the first chapter, we indicate the main methods for preparing the quinazoline ring, the pharmacological properties associated to the quinazoline-derivated drug compounds and we present the SRN1 reaction updated bibliography. In the second chapter, the synthesis and reactivity of 2-chloromethyl-3-methylquinazolin-4(3H)-one with nitronate and sulfinate anions are successively described. A mechanistic study permits to demonstrate the SRN1 radical chain mechanism for the reaction with nitronate anions and a SN2 one for sulfinate anions. Afterwards, we prepared new original quinazolines, under microwave irradiation, by studying SNAr and Suzuki-Miyaura coupling reactions in 4-chloroquinazoline series. From these results, we have developed a regioselective Suzuki-Miyaura reaction on the 4,7-dichloro-2-(2-methylprop-1-enyl)-6-nitroquinazoline and prepared a new series of highly functionalized 4,7-diarylquinazolines. Finally, the biological evaluation of the products prepared by SNAr, showed interesting antiplasmodial and anti-leishmania activities along with EGFR1 inhibition properties.
19

Gas-Phase Studies of Nucleophilic Substitution Reactions: Halogenating and Dehalogenating Aromatic Heterocycles

Donham, Leah L 01 January 2018 (has links)
Halogenated heterocycles are common in pharmaceutical and natural products and there is a need to develop a better understanding of processes used to synthesize them. Although the halogenation of simple aromatic molecules is well understood, the mechanisms behind the halogenation of aromatic heterocycles have been more problematic to elucidate because multiple pathways are possible. Recently, new, radical-based mechanisms have been proposed for heterocycle halogenation. In this study, we examine and test the viability of possible nucleophilic substitution, SN2@X, mechanisms in the halogenation of anions derived from the deprotonation of aromatic heterocycles. All the experiments were done in a modified Thermo LCQ Plus equipped with ESI. The modifications allow a neutral reagent to be added to the helium buffer gas in the 3D ion trap. In this system, it is possible to monitor ion/molecule reactions over time periods up to 10 seconds. A variety of aromatic heterocyclic nucleophiles were chosen based on their inclusion of nitrogen and or sulfur as the heteroatoms. In addition to this, the halogenating molecules chosen included traditional halobenzenes and a new class of perfluorinated alkyl iodides. It was found that, experimentally, the SN2@X path is the likely mechanism in the halogenation of deprotonated heterocycles. With computational modeling, we have additional support for this substitution mechanism. From this original study, two more studies were developed to look at the competing nucleophilic aromatic substitution reaction, SNAr. In the first of these studies, the focus was to look at how electron withdrawing substituents about an aromatic ring affect the ratio of SN2@X verses SNAr. As nucleophiles, 2-thiophenide and 5-thiazolide were used. The neutral reagents focus on trifluorobromobenzene derivatives along with pentafluorobromo- and -iodobenzene, and a two trifluoroiodobenzenes. What was found was that the ratio of the reactions depends on where the fluorines, or electron withdrawing substituents are in relation to the bromine or iodine on the ring. If the fluorines are in a close location to stabilize the resulting ionic product, SN2@X proceeds easily. However, the fluorines directly adjacent to the bromine or iodine also provide steric hinderance in the SNAr reaction. In the final project, arylation and benzylation of bromopyridines was examined. The nucleophiles used were benzyl and phenyl anions as well as 5-thiazolide, and the neutral reagents were bromopyridines, with fluorines used as an electron withdrawing groups to help stabilize the transition state. In these experiments, steric hinderance highly affected the results between the phenyl and benzyl nucleophiles. With benzylic anions, the nucleophile is able to reach the aromatic ring with less steric interference and therefore can proceed with an SNAr reaction. In addition to this, with mono and difluorinated pyridine substrates, the nitrogen in the ring activated the ring yielding nucleophilic aromatic substitution losing fluoride rather than bromide in many cases.
20

Kvantkemisk förutsägelse av regioselektivitet och reaktivitet hos SNAr-reaktioner / Quantum chemical prediction of regioselectivity and reactivity of SNAr reactions

Norstedt, Elias, Åkerlind, Gunnar, Robin, Fredrik, De Verdier, Olof January 2023 (has links)
Multivariate regression of several different quantum chemical descriptors was used to build a model for the reactivity of nucleophilic aromatic substitution reactions, i.e. SNAr reactions, through predictingthe molecular reaction site’s Gibb’s free activation energy (ΔG‡). The datasets used for training provided data of ΔG‡ for several differing halide leaving groups including chloride, bromide, and fluoride. A set of descriptors were tested for the different leaving groups revealing that dissimilar leaving groups are more dependent on certain descriptors than others, meaning each model has to be tailored for the specific leaving groups. Excellent correlations (R2 = 0.93) were achieved between the predicted ΔG‡ and the experimental ΔG‡.The ability of the model to predict regioselectivity in aromatic compounds with multiple leaving groups was tested and successfully predicted the correct regioselectivity through the calculation of ΔΔG‡ in each case tested. However, the model’s validity outside of the training dataset was put into doubt through low R2 values when the model was tested with several external datasets. An unknown factor arose which is speculated to be because of how differing nucleophiles and solvents affect the ΔG‡. One of these tests yielded excellent correlations (R2 = 0.9525) which could be because of similarities between solvents and nucleophiles between the training dataset but a similar factor between predicted ΔG‡ and the experimental ΔG‡ could still be observed.

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