Academic literature on the topic 'Chimie des arynes'

Riassunto: La politica religiosa di Commodo presenta due momenti significativi che corrispondono a due diversi atteggia­menti sia verso la religione tradizionale e, più in generale verso i culti esterni, sia verso il cristianesimo. La svolta matura soprattutto negli ultimi anni del suo reg­no quando Commodo opera una rottu­ra sia con il culto imperiale attraverso l’assimilazione a Ercole, che risulta tutta­via effimera, sia con la politica anticris­tiana di Marco che risulta più feconda e duratura in rapporto alle sorti del cristia­nesimo successivo.Abstract: Commodus’ religious policy shows two phases that correspond to two different attitudes both towards traditional religion and, more generally, to external cults, and towards Christianity. The breakthrough matured above all in the last years of his reign when Commodus made a break both with the imperial cult through as­similation to Hercules, which is however ephemeral, and with the anti-Christian policy of Marcus which is more fruitful and lasting in relation to the fate of subse­quent Christianity.Parole chiave: Commodo, Ercole, Culti tradizionali, Cristiani.Key words: Commodus, Hercules, Traditional Cults, Christians.

Riassunto: Quali edifici sono dedicati agli dei nel II secolo d.C.? Chi li pagava? Esiste una pre­dilezione per un particolare genere di edi­fici (funzionali, di recezione, sacri in senso stretto) a seconda che si tratti di interventi finanziati dall’imperatore o da una commit­tenza pubblica (i demi e i consigli locali), o che siano invece interventi privati? Questo articolo offre una rassegna delle principali tipologie di interventi edilizi e architettonici individuabili nel II secolo d.C. nei santuari del Peloponneso, esaminandoli in diacronia a seconda della loro funzione specifica (ter­me, teatri, edifici di assemblea) e mettendo in luce in che modo essi cambiarono la per­cezione e la vita quotidiana all’interno delle aree sacre.Abstract: Which buildings are dedicated to the gods in the 2nd century AD? Who paid for them? Is there a preference for a particu­lar kind of buildings (functional, recep­tion, sacred) depending on whether they are interventions financed by the emper­or or a public commission (the demi and local councils), or whether it is instead a private intervention? This article offers an overview of the main types of build­ing and architectural interventions that can be identified in the 2nd century AD. in the sanctuaries of the Peloponnesus, ex­amining them in diachrony according to their specific function (thermal buildings, theaters, assembly buildings) and high­lighting how they changed perception and daily life within the sacred areas.Parole chiave: Peloponneso, santuari, evergeti, impera­tori, dediche.Key words: Peloponnesus, sanctuaires, benefactors, imperators, dedications.

Resumen: Una piccola chiesa nell’Italia del nord (a Valdurna-Durnholz, nei pressi di Bolzano) esibisce dei dipinti risalenti al XV secolo in cui si ripresentano antichi motivi gnostico-alchemici. In essi un angelo lava l’anima e le impartisce un battesimo celeste, una immagine che troviamo anche in un testo della biblioteca di Nag Hammadi, il Vangelo di Filippo, in cui la purificazione dell’anima e descritta nei termini di un lavaggio e di una immersione in una sostanza detergente; un lessico che trae origine dalle operazioni di lavaggio e di tintura dei tessuti, in particolare dalle manipolazioni di natura alchimica. Ermetismo alchemico, gnosticismo e cristianesimo condividono infatti un comune intento soteriológico che si e trasmesso all’Occidente in forme spesso difficili da decifrare.Abstract: In a little church of northern Italy (in Valdurna-Durnholz, near Bolzano) we can find paintings from the fifteenth century where we have ancient Gnostic-Alchemical themes, again. These works, show an angel washing a soul and gives it the heavenly baptism, something that we find also in a Nag Hammadi text as the Gospel of Philip. In this text, the soul’s purification is described as an act of washing and dipping in a cleansing substance; this is a lexicon coming from the washing and the dying of clothes, and particularly from the Alchemical manipulations. Alchemical Hermeticism, Gnosticism and Christianity share a common soteriological view which has been passed to the West in ways often difficult to understand.Parole chiave: Arte cristiana, Gnosticismo, Testi di Nag Hammadi, Alchimia, ErmetismoKey words: Christian Art, Gnosticism, Nag Hammadi texts, Alchemy, Hermeticism

Riassunto: Antinoo rappresenta un tema caro alla let­teratura archeologica, anche recente, a causa del ruolo che il giovane riveste per Adriano, ma anche per la fascinazione che la sua bellez­za continua a esercitare. La parabola dei suoi ritratti ne riflette una di natura ideologica più complessa, che si può leggere come una vera e propria elaborazione dell’iconografia, cui co­rrisponde la progressiva costruzione del cul­to del Bitinico. Il presente articolo analizzerà contemporaneamente le informazioni offerte dalle fonti storiche su Adriano, quelle ricava­te dai testi geroglifici dell’obelisco del Pincio a Roma e le testimonianze poetiche trádite, sullo sfondo dell’ordinamento della città di Antinoupolis, attraverso le quali si narra parte del mito della morte e della successiva diviniz­zazione del giovane Antinoo.Abstract: Antinous is a subject loved by the archae­ological literature, even recent, due to the role that the young man plays for Hadrian, but also for the continuous fascination that his beauty inspires. The series of portraits reflects a sequence of a more complex ide­ological nature, which can be read as a true elaboration of iconography, corresponding to the progressive construction of the cult of the young Bitinic. The article will analyze the informations provided by the historical sources on Hadrian, by the hieroglyphic texts of the Pincius’ obelisk in Rome and the poetic texts preserved, looking at the background of the organization of the city of Antinoupolis, through which part of the myth of death and the subsequent deifica­tion of the young Antinous is told.Parole chiave: Antinoo, Egitto, imperatore Adriano, POxy 4352, ritratti.Key words: Antinous, Egypt, emperor Hadrian, POxy 4352, portraits.

Riassunto: In questo lavoro ci si propone di analizzare, attraverso le pagine degli autori latini, la costruzione semiotica sottostante la rappresentazione visuale degli dèi nella cultura romana; ognuno di loro possedeva infatti qualche attributo o combinazione di attributi in grado di identificarli con maggiore o minore certezza, ciò che gli autori antichi definivano insignia, dei “segni speciali” che guidavano l’interpretazione / identificazione di un signum. In particolare, saranno presi in esame alcuni oggetti concreti impiegati dalla cultura romana per costruire immagini divine nella loro funzione di attributi dotati di una specifica identità semiotica. A Roma vi erano altresì casi specifici in cui il potere dell’insigne risultava traboccante; la marca di riconoscibilità, in questi casi, era identificata con la totalità dell’immagine, così come l’immagine totale era ridotta e identificata con l’estensione della marca di riconoscimento: l’insigne, in questo caso, costituiva l’immagine. Questo ci porterà dunque a discutere i metodi di costruzione, adattamento, prestito e scarto delle immagini divine tra i politeismi antichi, delineando altresì prospettive comparative e analitiche.Abstract: In this work we aim to analyze, through the pages of the Latin authors, the semiotic construction underneath the visual representation of the gods in the Roman culture; each of them possessed some attribute or combination of attributes capable of identifying them with more or less certainty, what the ancient authors called insignia, the “special signs” that guided the interpretation / identification of a signum. In particular, some concrete objects will be examined, used by the Roman culture to construct divine images in their function of attributes endowed with a specific identity. In Rome there were also specific cases in which the power of the insigne was overflowing. The mark of recognizability, in these cases, was identified with the totality of the image, just as the image was reduced to the extension of the mark of recognition: the insigne, in that case, was the image. This will lead us to question the methods of construction, adaptation, borrowing and exclusion of divine images among ancient polytheisms, outlining comparative and analytical perspectives.Parole chiave: Appropriazione, identità, immagini divine, insignia, signa panthea, statua.Key words: Appropriation, divine images, identity, insignia, signa panthea, statue.

Les travaux développés au cours de cette thèse sont centrés sur le développement de réactions photochimiques en système microfluidique. Dans un premier temps, des dispositifs microstructurés fluidiques destinés à la photochimie à différentes longueurs d’onde ont été caractérisé à l’aide d’une technique d’actinométrie facile et rapide à mettre en place. Ce type de caractérisation est essentiel pour la reproductibilité des procédés et la maintenance des dispositifs. Cette technique d’actinométrie peut permettre à la fois la caractérisation du flux de photon émis par une source lumineuse de longueur d’onde connue mais également la caractérisation d’un photomicroréacteur fluidique. Le développement de réactions photochimiques en système microfluidique a ensuite été étudié. Ainsi, la photo-oxydation aérobie photocatalysée de sels de trifluoroborate benzyliques a été réalisée en flux segmenté avec des temps de séjour assez courts afin de former sélectivement des benzaldéhydes avec d’excellents rendements. Dans un deuxième temps, le mécanisme de photogénération ainsi que la nature de l’o-benzyne à partir l'o-2-carboxyphényltriazène ont pu être étudiés via différentes techniques analytiques. Ces études ont permis de mettre en évidence la formation de benzènediazonium-2-carboxylate comme intermédiaire réactionnel. Les paramètres cinétiques et thermodynamiques de la décomposition thermique du benzènediazonium-2-carboxylate en o-benzyne ont aussi été déterminés. De plus, un suivi par RPE de la photolyse de l'o-2-carboxyphényltriazène a permis de mettre en évidence la caractère bi-radicalaire à l’état triplet de l’o-benzyne. Nous avons ensuite développé le piégeage d’aryne avec différents arynophiles au moyen d'un photoréacteur microstructuré en flux continu thermorégulé. Le piégeage de l'o-benzyne avec des composés 1,3 dipolaires et des diènes a permis d’obtenir les cycloadduits correspondants avec des rendements bons à excellent et de bonne régiosélectivité. Enfin, le développement de nouveaux précurseurs d’arynes permettant la photogénération d’o-benzynes à des longueurs d’onde proche du visible a pu être exploré
The work developed during this thesis is focused on the development of photochemical reactions in microfluidic systems. Firstly, commercial microfluidic photoreactors were characterized via a rapid and easily implemented actinometry procedure. Indeed, the determination of photon flux received by the reaction mixture is crucial for the characterization of photochemical reactors, their maintenance and their dimensioning to obtain reproducible process. Moreover, (E)-azobenzene was introduced as a suitable chemical actinometer in the visible spectral range (440-540 nm) for photon flux determination of fluidic microphotoreactors. Photoisomerization quantum yields (ΦE→Z) of (E)-azobenzene were accurately determined upon irradiation at several wavelengths and in different solvents based on well-known diarylethene. In a second part, a simple continuous flow process for aerobic oxidation of benzylic organoboron compounds by photoredox catalysis under UV irradiation and Taylor regime was developed. Good to excellent yield by applying short residence times in combination with molecular oxygen as oxidant could be obtained. Finally, we developed a smooth generation protocol under fluidic conditions of o-benzyne from stable 2-carboxyphenyltriazene. Transient species such as arynes have been intensively investigated however, their short lifetimes and their reactive characters make them difficult to characterize and experimental structural data are limited. The mechanism of the o-benzyne formation has been probed through different spectroscopy methods. These studies suggest that under irradiation, photogenerated benzenediazonium 2-carboxylate intermediate lead to the formation of o-benzyne. After the determination of thermodynamics parameters, a highly efficient continuous photochemical benzyne–diene cycloaddition process with broad substrate scope was developed. Finally, the development of new o-benzyne photoprecursors in order to generate the transient species under a near-visible wavelength was investigated

La chimie des ortho-arynes (ou simplement arynes dans la suite de ce manuscrit), c’est-à-dire des arènes contenant formellement une triple liaison dans le cycle aromatique, a connu un regain d'intérêt au cours de la dernière décennie. Les arynes sont des espèces électrophiles très réactives empêchant leur isolement mais permettant leurs réactions avec un grand nombre d'arynophiles. Dans ce manuscrit, nous présentons les tendances actuelles de la chimie des arynes et notre propre travai ldans le domaine. Le but de notre travail était d'explorer l'utilisation de la cycloadditionaza-Diels–Alder entre les arynes et les aldimines comme un outil synthétique pour élaborer des architectures moléculaires originales pour des applications dans différents domaines, de la chimie médicinale aux matériaux. Dans une première approche, des séquences de cycloaddition aza-Diels–Alder / oxydation monotopes ont été développées pour la synthèse de benzo[e]-7-azaindoles protégés, qui ont été convertis en nucléosides par des réactions de couplage avec des dérivés du ribose. L'activité antivirale de ces molécules est à l'étude. Dans une autre approche, des séquences de cyclo addition aza-Diels–Alder/N-arylation en cascade ont été développées pour la synthèse d'hydroisoquinolines N-arylées, qui ont ensuite été converties en hydrocarbures polycycliques cationiques dopés N à chiralité axiale. Quelques unes de leurs propriétés physico-chimiques ont été évaluées par spectroscopies et modélisation. Dans l'ensemble, ces travaux indiquent que les arynes n'ont sans doute pas encore révélés leur plein potentiel en synthèse
The chemistry of ortho-arynes, that are arenes containing formally a triple bond inthe aromatic ring, has experienced a renewed interest in the last decade. Arynes areelectrophilic species with high reactivity precluding their isolation but allowing their reaction with a number of arynophiles. In this manuscript we present the current trends in aryne chemistry and our own work in the field. The aim of our work was to explore the use of the aza-Diels–Alder cycloaddition between arynes and aldimines asa synthetic tool to elaborate original molecular architectures for applications indifferent fields, from medicinal chemistry to materials. In a first approach, some one pot aza Diels-Alder cycloaddition / oxidation sequences were developed for the synthesis of protected benzo[e]-7-azaindoles, which were converted to nucleosides by coupling reaction with ribose derivatives. The antiviral activity of these molecules is under investigation. In another approach some cascade aza-Diels–Aldercycloaddition / N-arylation sequences were developed for the synthesis of N-arylated hydroisoquinolines, which were converted into cationic N-doped axially chiralpolyaromatic hydrocarbons. Some of their physicochemical properties were evaluated by spectroscopy and computational modeling. Over all this work indicates that arynes may not yet have revealed their full potential in synthesis

Dans ce manuscrit, nous décrivons comment nous avons développé la chimie des arynes atropisomères ayant une triple liaison réactive en ortho de l’axe stéréogène. Ces intermédiaires réactionnels sont facilement générés in situ et réagissent de manières énantiospécifiques, et permettent de synthétiser des atropisomères originaux. En particulier, nous décrivons la génération et des applications d’un équivalent synthétique de bis(aryne) atropisomère dérivé du BINOL, ainsi que la mesure semi-expérimentale de la barrière de réaction de tels arynes en présence d’un arynophile standard. À la fin du manuscrit, nous décrivons nos efforts pour développer une approche synthétique de deux triple hélicènes régioisomères
In this manuscript, we describe how we have developed the chemistry of aryne atropisomers with an ortho reactive triple bond to the stereogenic axis. These reaction intermediates are easily generated in situ and react in enantiospecific manners, and allow the synthesis of novel atropisomers. In particular, we describe the generation and applications of a synthetic equivalent of a BINOL-derived bis(aryne) atropisomer, as well as the semi-experimental measurement of the reaction barrier of such arynes in the presence of a standard arynophile. At the end of the manuscript, we describe our efforts to develop a synthetic approach to two regioisomers triple helices

Contrairement aux λ3-iodanes diaryliques bien étudiés, la chimie des dérivés λ3-bromane et λ3-chlorane a été rarement explorée en raison de leur synthèse complexe, occultant ainsi les applications potentielles. Nous nous sommes concentrés sur le développement de méthodes de synthèse efficaces pour les λ3-bromanes/chloranes (cyliques) diaryliques, ainsi que sur l'exploration de leur potentiel unique en tant que précurseurs d'arynes novateurs et leur réactivité en tant que réactifs efficace d’arylation. Les intermédiaires aryne, générés à partir de λ3-bromanes/chloranes, ont servi de plateformes synthétiques puissantes et durables pour la construction efficace de structures moléculaires complexes. De plus, l’insertion d'arynes dans les liaisons σ N–Si d’aminosilanes avec des réactifs λ3-bromanes/chloranes (cyliques) diaryliques a permis un accès direct à des dérivés 3-amino-2-silylbiaryls. Des investigations expérimentales mécanistiques, combinées à des calculs DFT, ont été menées pour élucider la réactivité distincte et améliorée des réactifs (cyliques) diaryliques de brome(III) et de chlore(III) dans transformations chimiques
In contrast to well-studied diaryl λ3-iodanes, the chemistry of λ3-bromane and λ3-chlorane congeners has been scarcely explored due to their challenging synthesis, shadowing their potential applications. For this purpose, we focused on developing the practical and efficient synthetic methods for (cyclic) diaryl λ3-bromanes/chloranes, as well as exploring their unique as novel aryne precursors and superior reactivity as enhanced arylating reagents. The aryne intermediates, generated from (cyclic) diaryl λ3-bromanes/chloranes, served as a potent and sustainable synthetic platforms for a straightforward and efficient construction of complex molecular frameworks. In addition, aryne insertion into N–Si σ-bonds of aminosilanes with cyclic diaryl λ3-bromane/chlorane reagents enabled a direct access to 3-amino-2-silylbiaryl derivatives. Experimental mechanistic investigations, combined with DFT calculations, were further conducted to elucidate the distinct and enhanced reactivity of the rarely explored (cyclic) diaryl hypervalent bromine(III) and chlorine(III) reagents in diverse and versatile chemical transformations

Reaction d'electrosynthese des liaisons carbone-carbone: addition de radicaux aryles produits par electrochimie-reduction des derives aromatiques halogenes sur des doubles liaisons olefiniques. Etudes theorique et experimentale. Discussion de la regioselectivite des reactions

Graphene is an allotrope of carbon material with a unique set of properties. Since it discovery in 2004 the number of publications about this material grew really fast. In the first chapter of this work, a general introduction of these topics, an overview of this material and relevant characterization techniques is described. Chemical functionalization of graphene is a topic of paramount importance, because it allows for the fine-tuning of material’s chemical and physical properties. An additional challenge in graphene functionalization is the surface modification in a controlled way, in order to create novel carbon interfaces to introduce functional biomolecules, like DNA or proteins, which are often used in biosensors and bioelectronics. Chapter 2 discuss the exploration of conventional routes for the preparation and functionalization of graphene. With special emphasis in the underexplore aryne cycloadditions. Besides, the selection of a suitable graphene material for the setting of an electrochemical functionalization of graphene electrodes with future application as biosensor platforms. Moreover, the development of an early-stage essay biosensor of a modified graphene electrode for the electrochemical detection of oligonucleotides. By last, the study of a novel, fast and scalable non-conventional functionalization under microwave irradiation that can solve common problems of the conventional modifications of carbon materials. The present results could open a range of possibilities for the scientific community, paving the way to new functionalization protocols with fast, efficient, large-scale and green procedures to obtain more user-friendly graphene materials and to create novel organic interfaces on diverse graphene derivatives for the manufacture of future biosensors and bioelectronic devices.

Synthese d'un macrocycle forme de deux sous-unites phenazines substituees en 2,7 et maintenues face a face par des ponts diacetyleniques; interactions des chlorures de ces composes avec des molecules planes telles que le terephtalate, le naphtalenedicarboxylate-2,6 et des polynucleotides

L’objectif de ce travail de thèse est de développer une nouvelle voie d’accès aux hétérobiaryles à chiralité axiale selon une stratégie de synthèse atropoénantiosélective réalisée en l’absence de métaux de transition. Le projet combine une méthode de construction de la liaison Csp2-Csp2 appelée couplage Aryne, et une approche énantiosélective, le concept ICE (ionic chiral environment). Ce concept repose sur la mise en œuvre de ligands chiraux en tant que stabilisants du métal (Li) à partir d’un partenaire de couplage organolithié. L’environnement chiral résultant des agrégats chiraux générés doit permettre d’induire la chiralité lors de l’étape de couplage. La première partie de ce travail a consisté à développer une version hétérocyclique du couplage Aryne en conditions achirales. Les résultats obtenus à l’issue de cette étude ont permis de relier la nature électronique du partenaire hétérocyclique à sa réactivité dans le couplage. Le thiophène en particulier a fourni de très bons résultats ce qui nous a permis de développer davantage la méthode. La seconde partie de ce travail a eu pour objectif de développer le couplage étudié dans des conditions de solvants adaptées à la formation des agrégats mixtes chiraux envisagés. Cette étude a permis de mettre en évidence l’influence remarquable d’une gamme de plusieurs ligands (polyéthers, polyamines, aminoalcoolates,…) et sels (Li, Zn, K,…) sur le couplage développé en solvant apolaire. Par la suite, les conditions de couplages optimales ont été étendues à différents hétérocycles avec succès. En parallèle, des calculs théoriques de la densité fonctionnelle ont permis d’appuyer plusieurs de nos résultats ; ces calculs ont également fourni une analyse détaillée du mécanisme du couplage Aryne. Enfin, la dernière partie de ce manuscrit a concerné le couplage d’un partenaire hétérocyclique encombré des dérivés du thiophène et du benzothiophène
The aim of this thesis work was to provide novel access to axially chiral heterobiaryls following a transition metal free atropoenantioselective synthetic route. This project combines the Csp2-Csp2 Aryne coupling methodology, and an enantioselective approach, the ICE concept (ionic chiral environment). This concept relies on the implementation of chiral ligands as metal (Li) stabilizers with organolithium coupling partners. The chiral environment resulting from the chiral aggregates obtained must induce chirality during the coupling step. The first part of this work aimed to develop an heterocyclic version of the Aryne route in achiral conditions. The results of this study revealed a clear correlation between the electronic nature of the heterocyclic partner and its reactivity in the Aryne coupling. Thiophene, especially, proved to furnish promising results and allowed us to further develop the method. Second part of this work aimed to develop the reaction in the appropriate solvent conditions so that chiral mixed metal aggregates could be envisioned. This study outlined the remarkable effect of external chelating ligands (polyethers, polyamines, aminoalkoxides,…) and salt additives (Li, Zn, K,…) on the aryne coupling reaction in apolar media. The best reaction conditions emerging from this work were then successfully applied to others heterocyclic coupling partners. In parallel, theoretical calculations using density functional theory showed good agreement with experimental work and allowed us to propose mechanistic scheme for the reaction. Last part of this work focused on the reaction of hindered heterocyclic coupling partners with thiophene and benzothiophene derivatives