1,234 research outputs found
Coupling and Dearomatization of Pyridines at a Transient (2)-Cyclopropene/Bicyclobutane Zirconocene Complex
No full textbibtex: ISI:000414633200027 bibtex\location:'POSTFACH 101161, 69451 WEINHEIM, GERMANY',publisher:'WILEY-V C H VERLAG GMBH',type:'Article',affiliation:'Etienne, M (Reprint Author), CNRS, LCC, 205 Route Narbonne,BP44099, F-31077 Toulouse, France. Etienne, M (Reprint Author), Univ Toulouse, UPS, INPT, LCC, F-31077 Toulouse, France. Romero, Nuria; Dufrois, Quentin; Vendier, Laure; Dinoi, Chiara; Etienne, Michel, CNRS, LCC, 205 Route Narbonne,BP44099, F-31077 Toulouse, France. Romero, Nuria; Dufrois, Quentin; Vendier, Laure; Dinoi, Chiara; Etienne, Michel, Univ Toulouse, UPS, INPT, LCC, F-31077 Toulouse, France. Romero, Nuria, Univ Autonoma Barcelona, Dept Quim, Cerdanyola Del Valles Ba 08193, Spain. Dinoi, Chiara, LPCNO INSA, 135 Ave Rangueil, F-31077 Toulouse, France.','author-email':'[email protected]',da:'2018-12-05','doc-delivery-number':'FM0EI',eissn:'1521-3765','funding-acknowledgement':'MENESR [ANR-11-BS07-0009]; COST Action CHAOS [CA15106]','funding-text':'We thank the MENESR for a PhD grant to QD, the ANR (Green-LAkE project; ANR-11-BS07-0009) and COST Action CHAOS (CA15106) for support.','journal-iso':'Chem.-Eur. J.','keywords-plus':'AROMATIC N-HETEROCYCLES; CH BOND ACTIVATION; CRYSTAL-STRUCTURES; ALKYL COMPLEXES; H BONDS; METAL; CHEMISTRY; ETA(2)-CYCLOPROPENE; ORGANOZIRCONIUM; NIOBIUM','number-of-cited-references':'42','orcid-numbers':'Romero, Nuria/0000-0002-2704-7779 Vendier, Laure/0000-0002-7111-9258 Etienne, Michel/0000-0002-1099-3232','research-areas':'Chemistry','researcherid-numbers':'Romero, Nuria/A-9756-2016','times-cited':'0','unique-id':'ISI:000414633200027','usage-count-last-180-days':'4','usage-count-since-2013':'12','web-of-science-categories':'Chemistry, Multidisciplinary'\International audienceThis paper reports on stereospecific coupling reactions between an (2)-cyclopropene ligand and pyridine derivatives, which are preferred to alternative C-H bond activation reactions. The dicyclopropylzirconocene complex [Cp2Zr(c-C3H5)(2)](1) eliminates cyclopropane to generate the (2)-cyclopropene/bicyclobutane intermediate [Cp2Zr((2)-c-C3H4)](A). A does not activate any pyridine C-H bonds, but rather pyridine inserts into a Zr-C bond of A, yielding an azazirconacycle with a dearomatized pyridyl group [Cp2Zr\(2)-N,C-8-(2-c-C3H4)-C5H5N\](2). Kinetic data, isotopelabelling experiments, and DFT calculations indicate that the rate-determining step of this stereospecific reaction is cyclopropane elimination, and that the stability of the intermediate [Cp2Zr((2)-c-C3H4)(NC5H5)](A-py) governs the selectivity of the reaction. Complex2 tautomerizes to [Cp2Zr\(2)-N,C-8-(2-C3H5)-C5H4N\](6) through a base-catalyzed proton migration accompanied by cyclopropyl opening and restoration of conjugation within the zirconacycle
Complexes de métaux électropositifs à travers le prisme du groupe cyclopropyle
No full textLa thèse présente la chimie de complexes de métaux électropositifs portant le groupe cyclopropyle. La première partie du manuscrit décrit la synthèse et la caractérisation de dérivés du cyclopropyllithium ayant pour formule [1-R-c-C3H4Li] (R = SiMe3, Ph, SPh). Des agrégats originaux, organisés autour de centres Li+ stabilisés par la peu commune interaction CC agostique, sont présentés. Cette interaction a une influence marquée sur l'agrégation des composés à l'état solide et parfois en solution. Sa coordination compétitive, sur un Li+, avec des atomes donneurs (O, N et S) permet une évaluation qualitative de sa force. La deuxième partie du manuscrit présente la synthèse du nouveau complexe cyclopropylcalcium. Ce composé est caractérisé par une étude RMN complète. C'est le premier alkylcalcium non-stabilisé. La troisième partie du manuscrit contient une étude de la réactivité du dicyclopropylzirconocene [Cp2Zr(c-C3H5)2] vis-à-vis de la pyridine et de pyridines fluorées. La formation d'un intermédiaire Eta2-cyclopropene mène à la déaromatisation et à l'activation C-H de la pyridine, mais aussi à l'activation C-F de la pentafluoropyridine. Une étude préliminaire de l'activation catalytique de la liaison C-F de la pentafluoropyridine par [Cp2Zr(c-C3H5)2] en présence de tricyclopropylaluminium est aussi présentée.The manuscript presents the chemistry of electropositive metal complexes bearing the cyclopropyl group. This first part of the manuscript describes the synthesis and characterisation of cyclopropopyllithium derivatives of the formula [1-R-c-C3H4Li] (R = SiMe3, Ph, SPh). Original aggregates displaying low valent Li+ centres stabilised by the rare CC agostic interaction are presented. This interaction influences the aggregation of the compounds in the solid state and sometimes in solution. A qualitative evaluation of its strength is provided by competitive coordination on Li+ vs donor atoms such as O, N and S. The second part of the manuscript presents the synthesis of the new cyclopropylcalcium complex. This compound is characterised by a full NMR study. It is the first non-stabilised alkylcalcium compound. The third part of the manuscript contains a reactivity study of dicyclopropylzirconocene [Cp2Zr(c-C3H5)2] towards pyridine and fluorinated pyridines. Dearomatisation and C-H bond activation of pyridine, together with C-F bond activation of pentafluoropyridine result from the initial formation of a Eta2-cyclopropene intermediate. A preliminary study of the catalytic C-F bond cleavage of pentafluoropyridine by [Cp2Zr(c-C3H5)2] in the presence of tricyclopropylaluminium is also presented
The author as actor: a defense of Quentin Skinner
No full textIn this thesis, I defend Quentin Skinner's work against some criticisms raised by three of his interlocutors: John Keane, Kennet Minogue, and Joseph Femia. All three of these critics take issue with Skinner's author-centered approach to the historical interpretation of texts. Femia, invoking Roland Barthes 'death of the author' thesis, argues that Skinner's attempt to recover the intentions of authors is impossible. While Minogue and Keane do not dispute the possibility of recovering an author's intentions, they question the unity of such an enterprise. In order to answer Femia's criticism of Skinner, I draw an analogy between Skinner's figure of the author, and Arendt's figure of the political actor. I argue that just as it is possible for someone to know what a political actor is doing in performing a political act, it is similarly possible for an intellectual historian to understand what political acts an author was doing in writing his or her text. To refute Minogue's and Keane's claims that a Skinnerian approach to intellectual history is of no use to the political theorist, I point to three examples of how Skinner's recovery of forgotten political discourses have been applied to contemporary debates in political theory.Graduat
Electropositive metal complexes through the prism of the cyclopropyl group
No full textLa thèse présente la chimie de complexes de métaux électropositifs portant le groupe cyclopropyle. La première partie du manuscrit décrit la synthèse et la caractérisation de dérivés du cyclopropyllithium ayant pour formule [1-R-c-C3H4Li] (R = SiMe3, Ph, SPh). Des agrégats originaux, organisés autour de centres Li+ stabilisés par la peu commune interaction CC agostique, sont présentés. Cette interaction a une influence marquée sur l'agrégation des composés à l'état solide et parfois en solution. Sa coordination compétitive, sur un Li+, avec des atomes donneurs (O, N et S) permet une évaluation qualitative de sa force. La deuxième partie du manuscrit présente la synthèse du nouveau complexe cyclopropylcalcium. Ce composé est caractérisé par une étude RMN complète. C'est le premier alkylcalcium non-stabilisé. La troisième partie du manuscrit contient une étude de la réactivité du dicyclopropylzirconocene [Cp2Zr(c-C3H5)2] vis-à-vis de la pyridine et de pyridines fluorées. La formation d'un intermédiaire Eta2-cyclopropene mène à la déaromatisation et à l'activation C-H de la pyridine, mais aussi à l'activation C-F de la pentafluoropyridine. Une étude préliminaire de l'activation catalytique de la liaison C-F de la pentafluoropyridine par [Cp2Zr(c-C3H5)2] en présence de tricyclopropylaluminium est aussi présentée.The manuscript presents the chemistry of electropositive metal complexes bearing the cyclopropyl group. This first part of the manuscript describes the synthesis and characterisation of cyclopropopyllithium derivatives of the formula [1-R-c-C3H4Li] (R = SiMe3, Ph, SPh). Original aggregates displaying low valent Li+ centres stabilised by the rare CC agostic interaction are presented. This interaction influences the aggregation of the compounds in the solid state and sometimes in solution. A qualitative evaluation of its strength is provided by competitive coordination on Li+ vs donor atoms such as O, N and S. The second part of the manuscript presents the synthesis of the new cyclopropylcalcium complex. This compound is characterised by a full NMR study. It is the first non-stabilised alkylcalcium compound. The third part of the manuscript contains a reactivity study of dicyclopropylzirconocene [Cp2Zr(c-C3H5)2] towards pyridine and fluorinated pyridines. Dearomatisation and C-H bond activation of pyridine, together with C-F bond activation of pentafluoropyridine result from the initial formation of a Eta2-cyclopropene intermediate. A preliminary study of the catalytic C-F bond cleavage of pentafluoropyridine by [Cp2Zr(c-C3H5)2] in the presence of tricyclopropylaluminium is also presented
Complexes de métaux électropositifs à travers le prisme du groupe cyclopropyle
No full textThe manuscript presents the chemistry of electropositive metal complexes bearing the cyclopropyl group. This first part of the manuscript describes the synthesis and characterisation of cyclopropopyllithium derivatives of the formula [1-R-c-C3H4Li] (R = SiMe3, Ph, SPh). Original aggregates displaying low valent Li+ centres stabilised by the rare CC agostic interaction are presented. This interaction influences the aggregation of the compounds in the solid state and sometimes in solution. A qualitative evaluation of its strength is provided by competitive coordination on Li+ vs donor atoms such as O, N and S. The second part of the manuscript presents the synthesis of the new cyclopropylcalcium complex. This compound is characterised by a full NMR study. It is the first non-stabilised alkylcalcium compound. The third part of the manuscript contains a reactivity study of dicyclopropylzirconocene [Cp2Zr(c-C3H5)2] towards pyridine and fluorinated pyridines. Dearomatisation and C-H bond activation of pyridine, together with C-F bond activation of pentafluoropyridine result from the initial formation of a Eta2-cyclopropene intermediate. A preliminary study of the catalytic C-F bond cleavage of pentafluoropyridine by [Cp2Zr(c-C3H5)2] in the presence of tricyclopropylaluminium is also presented.La thèse présente la chimie de complexes de métaux électropositifs portant le groupe cyclopropyle. La première partie du manuscrit décrit la synthèse et la caractérisation de dérivés du cyclopropyllithium ayant pour formule [1-R-c-C3H4Li] (R = SiMe3, Ph, SPh). Des agrégats originaux, organisés autour de centres Li+ stabilisés par la peu commune interaction CC agostique, sont présentés. Cette interaction a une influence marquée sur l'agrégation des composés à l'état solide et parfois en solution. Sa coordination compétitive, sur un Li+, avec des atomes donneurs (O, N et S) permet une évaluation qualitative de sa force. La deuxième partie du manuscrit présente la synthèse du nouveau complexe cyclopropylcalcium. Ce composé est caractérisé par une étude RMN complète. C'est le premier alkylcalcium non-stabilisé. La troisième partie du manuscrit contient une étude de la réactivité du dicyclopropylzirconocene [Cp2Zr(c-C3H5)2] vis-à-vis de la pyridine et de pyridines fluorées. La formation d'un intermédiaire Eta2-cyclopropene mène à la déaromatisation et à l'activation C-H de la pyridine, mais aussi à l'activation C-F de la pentafluoropyridine. Une étude préliminaire de l'activation catalytique de la liaison C-F de la pentafluoropyridine par [Cp2Zr(c-C3H5)2] en présence de tricyclopropylaluminium est aussi présentée
Drawing Sacred Forests and Courtyards in South Benin
No full texthttps://drawingmatter.org/drawing-sacred-forests-and-courtyards-in-south-benin/The following conversation between the editors of Accattone and Quentin Nicolaï was first published in Accattone 6 (2019). It documents research carried out by Quentin Nicolaï in Abomey, Benin, between January 2014 and June 2018.Drawing Matter would like to thank the author and the magazine’s editors for allowing us reproduce the essay on www.drawingmatter.org.info:eu-repo/semantics/nonPublishe
Features of auteur cinema in Quentin Tarantino's works
No full textMultimediju komunikācijaInformācijas un komunikācijas zinātnesMultimedia CommunicationInformation and Communication SciencesBakalaura darba tēmas nosaukums ir “Autorkino iezīmes Kventina Tarantīno daiļradē.”
Pētījumā izvirzītā hipotēze apgalvo, ka režisora Kventina Tarantīno (Quentin Tarantino) filmās ir
atrodamas autorkino iezīmes.
Bakalaura darba mērķis ir noskaidrot autorkino iezīmes Kventina Tarantīno sešās
ietekmīgākajās un skatītāju atzītākajās filmās, kuras tika atlasītas pēc Internacionālās filmu datu
bāzes. Darbā tiek apskatītas un analizētas sešas no Kventina Tarantīno filmām, kuras ir “Trakie
suņi” (Reservoir Dogs), “Lubene” (Pulp Fiction), “Nogalināt Bilu: 1. daļa” (Kill Bill: Vol. 1) un
“Nogalināt Bilu: 2. daļa” (Kill Bill: Vol. 2), kas pēc paša režisora uzskatiem ir, viena vesela, filma
sadalīta divās daļās, kā arī filmas “Bēdīgi slavenie mērgļi” (Inglorious Bastards), “Atsvabinātais
Džango” (Django Unchained) un “Reiz Holivdā” (Once Upon a Time... in Hollywood).
Darba mērķa izpildei teorētiskajā daļā tika aplūkots autorkino jēdziens, Holivudas
klasiskais kino stils, kino valoda, kā arī Kventina Tarantīno biogrāfija, lai palīdzētu izprast un
analizēt atlasītās filmas. Par pētījuma metodi tika izvēlēta kvalitatīvā kontentanalīze.The title of the bachelor's thesis is "Features of auteur cinema in Quentin Tarantino's
works" The study’s hypothesis states that directors Quentin's Tarantino's films have the features
of an author.
The purpose of the bachelor's thesis is to find out the influence of author cinema on Quentin
Tarantino's six most influential and audience-recognized films selected from the International Film
Database. Work is discussed and analyzed in six of Quentin Tarantino films, which are “Reservoir
Dogs”, “Pulp Fiction”, “Kill Bill: Vol. 1” and “Kill Bill: Vol. 2”, which the director says is a whole
movie divided into two parts, as well as “Inglorious Bastards”, “Django Unchained” and “Once
Upon a Time ... in Hollywood”.
The theoretical part of the paper explored the concept of author cinema, Hollywood classic
cinema, film language, and the biography of Quentin Tarantino to help understand and analyze
selected films. Qualitative content analysis was chosen as the research method
Saint-Quentin et sa région
No full textThe author insists on the seriousness of the trade depression in Saint-Quentin last years (ten per cent workmen out of work, unemployed period above eleven months.). Metallurgy is the principal industry and «Motobécane» the first firm, making the famous «Mobylette» since 1951. Therefore, the difficulties of «Motobécane», of the engineering industry, have effects on the social situation. The town is, from now on, the starting point of an urban emigration. Old fortress on the right bank, protecting the crossing of the river Somme, Saint-Quentin has been destroyed during the first World War and rebuilt without large transformation. The town keeps an heptagonal shape with cross-roads on the both sides of the valley, canal and railway. The attraction area is, to-day, smaller than the Vermandois, very industrialized and populated region. For the future, Saint-Quentin shall have to expect : the «A-26 » motorway, the négociation of an employment agreement («Contrat de Bassin d'Emploi») and, later, the construction of the large-gauge canal «Seine-Nord» from Compiègne to Valenciennes.L'auteur insiste sur la gravité de la crise de remploi à Saint-Quentin aujourd 'hui (taux de chômage supérieur à 1 0%, durée moyenne de chômage supérieure à 11 mois). L'industrie est dominée par la métallurgie et celle-ci par la firme «MOTOBECANE» qui fabrique depuis 1951 les fameuses «mobylettes». Aussi les difficultés de Motobécane ou de l'industrie de la manutention rejaillissent-elles immédiatement sur la situation sociale. La ville est désormais le point de départ d'un véritable exode urbain. Ancienne place forte gardant, sur la rive droite , le passage de la Somme, presque complètement détruit en 1918, mais reconstruit largement à l'identique, St-Quentin a hérité d'une double structure heptagonale et en «patte d'oie» de part et d'autre de la coupure majeure de la vallée de la Somme (canal et voie ferrée). Son aire d'attraction s'est réduite par rapport à la région qui l'entoure, le Vermandois, relativement peuplé et industrialisé lui-même. Pour l'avenir, St-Quentin doit compter surtout, sur l'arrivée de l'autoroute A 26 et sur les efforts qui s'inscriront dans un «Contrat de Bassin d'Emploi», et, à long terme sur la liaison fluviale à grand gabarit «Seine-Nord» utilisant le tracé du canal de St-Quentin.Oudart Paul. Saint-Quentin et sa région. In: Hommes et Terres du Nord, 1981/2. Spécial Picardie. pp. 43-56
A Hundred Years of Photo Wallets:Quentin Blake Centre for Illustration's Book of the Month
No full textAn interview with Annebella Pollen, author of More Than a Snapshot: A Visual History of Photo Wallets, which was selected as the May 2023 Book of the Month by the Quentin Blake Centre for Illustration
Quentin Meillassoux: Facticity and Scientific Methods
No full textThis paper examines Quentin Meillassoux’s critique of correlationism, specifically focusing on the Principle of Factuality and the mathematization of hyperchaos as tools to access the "ancestral." While acknowledging Meillassoux’s significance in overcoming Kantian limits, the author argues that his refusal to return to metaphysics stems from political hesitation rather than ontological necessity. The text critiques the concept of the "God to come" as an ideological compromise. Instead, the author advocates for an "experimental metaphysics" grounded in scientific method, positing that science offers rational access to the absolute and effectively resolving the tension between facticity and the thing-in-itself
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