Literatura académica sobre el tema "[2+2+2] cycloaddition"

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Artículos de revistas sobre el tema "[2+2+2] cycloaddition"

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Grygorenko, Oleksandr O., Viktoriia S. Moskvina, Oleksandr V. Hryshchuk, and Andriy V. Tymtsunik. "Cycloadditions of Alkenylboronic Derivatives." Synthesis 52, no. 19 (2020): 2761–80. http://dx.doi.org/10.1055/s-0040-1707159.

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The literature on cycloaddition reactions of boron-containing alkenes is surveyed with 132 references. The data are categorized according to the reaction type ([2+1], [2+2], [3+2], [4+2], and [4+3] cycloadditions). The cyclopropanation and the Diels–Alder reactions of alkenylboronic derivatives have been studied more or less comprehensively, and for some substrates, they can be considered as convenient methods for the rapid regio- and stereoselective construction of even complex cyclic systems. Other types of the cycloadditions, as well as mechanistic aspects of the processes, have been addressed less thoroughly in the previous works.1 Introduction2 [2+1] Cycloaddition2.1 Cyclopropanation2.1.1 With Methylene Synthetic Equivalents2.1.2 With Substituted Carbenoids2.2 Epoxidation2.3 Aziridination3 [2+2] Cycloaddition4 [3+2] Cycloaddition4.1 With Nitrile Oxides4.2 With Diazoalkanes4.3 With Nitrones4.4 With Azomethine Ylides5 [4+2] Cycloaddition6 [4+3] Cycloaddition7 Conclusions and Outlook
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Kotha, Sambasivarao, Kakali Lahiri, and Gaddamedi Sreevani. "Design and Synthesis of Aromatics through [2+2+2] Cyclotrimerization." Synlett 29, no. 18 (2018): 2342–61. http://dx.doi.org/10.1055/s-0037-1609584.

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The [2+2+2] cycloaddition reaction is a useful tool to realize unusual chemical transformations which are not achievable by traditional methods. Here, we report our work during the past two decades that involve utilization of transition-metal complexes in a [2+2+2] cyclotrimerization reaction. Several key “building blocks” were assembled by a [2+2+2] cycloaddition approach and they have been further expanded by other synthetic transformations to design unusual amino acids and peptides, diphenylalkanes, bis- and trisaryl benzene derivatives, annulated benzocycloalkanes, spirocycles, and spirooxindole derivatives. Furthermore, we have also discussed about alkyne surrogates, environmentally friendly, and stereoselective [2+2+2] cycloaddition reactions. Application of the [2+2+2] cycloaddition reaction in total synthesis is also covered. In this review we also included others work to give a balanced view of the recent developments in the area of [2+2+2] cycloaddition.1 Introduction2 Unusual Amino Acids and Peptides3 Heteroanalogues of Indane4 Diphenylalkane Derivatives5 Multi-Armed Aryl Benzene Derivatives6 Annulated Benzocycloalkanes7 Spirocycles8 Selectivity in [2+2+2] Cycloaddition of Alkynes9 [2+2+2] Cycloaddition Reactions under Environmentally Friendly Conditions10 Alkyne Surrogates11 Domino Reactions involving a [2+2+2] Cycloaddition12 Biologically Important Targets/Total Synthesis13 Conclusions
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Ahmad, Dalla Tiezza, and Orian. "In Silico Acetylene [2+2+2] Cycloadditions Catalyzed by Rh/Cr Indenyl Fragments." Catalysts 9, no. 8 (2019): 679. http://dx.doi.org/10.3390/catal9080679.

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Metal-catalyzed alkyne [2+2+2] cycloadditions provide a variety of substantial aromatic compounds of interest in the chemical and pharmaceutical industries. Herein, the mechanistic aspects of the acetylene [2+2+2] cycloaddition mediated by bimetallic half-sandwich catalysts [Cr(CO)3IndRh] (Ind = (C9H7)−, indenyl anion) are investigated. A detailed exploration of the potential energy surfaces (PESs) was carried out to identify the intermediates and transition states, using a relativistic density functional theory (DFT) approach. For comparison, monometallic parent systems, i.e., CpRh (Cp = (C5H5)−, cyclopentadienyl anion) and IndRh, were included in the analysis. The active center is the rhodium nucleus, where the [2+2+2] cycloaddition occurs. The coordination of the Cr(CO)3 group, which may be in syn or anti conformation, affects the energetics of the catalytic cycle as well as the mechanism. The reaction and activation energies and the turnover frequency (TOF) of the catalytic cycles are rationalized, and, in agreement with the experimental findings, our computational analysis reveals that the presence of the second metal favors the catalysis.
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Kanematsu, Ken, Noboru Sugimoto, Masayo Kawaoka, Sinkoo Yeo, and Motoo Shiro. "Competitive intramolecular [4+2] cycloaddition and [2+2] cycloaddition of sulfonylallene." Tetrahedron Letters 32, no. 10 (1991): 1351–54. http://dx.doi.org/10.1016/s0040-4039(00)79665-1.

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Tanaka, K., K. Masutomi, N. Sakiyama, and K. Noguchi. "Rhodium-Catalyzed Asymmetric [2+2+2] Cycloaddition." Synfacts 9, no. 05 (2013): 0575. http://dx.doi.org/10.1055/s-0033-1338458.

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Rovis, T., and D. Dalton. "Rhodium-Catalyzed Enantioselective [2+2+2] Cycloaddition." Synfacts 9, no. 09 (2013): 1030. http://dx.doi.org/10.1055/s-0033-1339688.

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Meyer, Vera J., Christoph Ascheberg, and Meike Niggemann. "Calcium-Catalyzed Formal [2+2+2] Cycloaddition." Chemistry - A European Journal 21, no. 17 (2015): 6371–74. http://dx.doi.org/10.1002/chem.201500181.

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Fleming, Steven A., and Susan C. Ward. "Stereocontrolled photochemical [2 + 2] cycloaddition." Tetrahedron Letters 33, no. 8 (1992): 1013–16. http://dx.doi.org/10.1016/s0040-4039(00)91847-1.

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Treutwein, Jonas, and Gerhard Hilt. "Cobalt-Catalyzed [2+2] Cycloaddition." Angewandte Chemie International Edition 47, no. 36 (2008): 6811–13. http://dx.doi.org/10.1002/anie.200801778.

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Treutwein, Jonas, and Gerhard Hilt. "Cobalt-katalysierte [2+2]-Cycloaddition." Angewandte Chemie 120, no. 36 (2008): 6916–19. http://dx.doi.org/10.1002/ange.200801778.

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Tesis sobre el tema "[2+2+2] cycloaddition"

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Wan, Honghe. "Allenes and (2+2+1) cycloaddition reactions." Morgantown, W. Va. : [West Virginia University Libraries], 1998. http://etd.wvu.edu/templates/showETD.cfm?recnum=195.

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Thesis (M.S.)--West Virginia University, 1998.
Title from document title page. Document formatted into pages; contains xii, 99 p. : ill. Includes abstract. Includes bibliographical references (p. 93-99).
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Haraburda, Ewelina. "[2+2+2] cycloaddition reactions involving allenes catalysed by rhodium." Doctoral thesis, Universitat de Girona, 2015. http://hdl.handle.net/10803/328439.

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The development of new chemical processes for the formation of carbon-carbon bonds is an important topic in organic chemistry. In particular, the transition metal catalysed [2+2+2] cycloaddition reaction is a highly efficient synthetic tool that allows six-membered polysubstituted carbo- and heterocyclic derivatives to be obtained in an atom economy process. Allenes are versatile substrates for cycloaddition reactions that provide a good reactivity profile together with the ability to increase the stereochemical complexity of the cycloadducts obtained. This doctoral thesis, divided into seven different chapters, is based on the methodological study of the rhodium(I)-catalysed [2+2+2] cycloaddition reaction involving allenes. Chapter 1 contains a general introduction to the structural and reactivity particularities of allenes and to the [2+2+2] cycloaddition reactions, making reference to the main examples found in the literature. Chapter 2 sets out the general objectives of the thesis. In Chapters 3 and 4 the reactivity of linear chiral and non-chiral allene-ene/yne-allene substrates in totally intramolecular rhodium-catalysed [2+2+2] cycloaddition is evaluated. In Chapter 5, a dehydrogenative [2+2+2] cycloaddition of cyano-yne-allene substrates is developed which allows for the synthesis of the 2,6-naphthyridines core found in biologically relevant products. Chapter 6 draws general conclusions from the results of these studies. Finally, Chapter 7 contains the experimental procedure and the characterization data for the compounds synthesised in this thesis.
El desarrollo de nuevos procesos químicos para la formación de enlaces carbono-carbono es un campo importante en química orgánica. Concretamente, la reacción de cicloaddición [2+2+2] catalizada por metales de transición es una herramienta muy eficiente que permite la formación de derivados carbo- y heterocíclicos polisustituidos de seis miembros en un proceso de economía atómica. Por otro lado, los alenos son sustratos versátiles en reacciones de cicloadición que además de poseer un buen perfil de reactividad tienen la habilidad de incrementar la complejidad estructural en los cicloaductos que permiten sintetizar. La presente tesis doctoral, dividida en siete capítulos, se ha basado en el estudio metodológico de cicloadiciones [2+2+2] catalizadas por rodio(I) involucrando alenos. El Capítulo 1 contiene una introducción general a las particularidades estructurales y de reactividad de los alenos y a las reacciones de cicloadición [2+2+2] haciendo referencia a los principales ejemplos descritos en la bibliografía. El Capítulo 2 presenta los objetivos generales de la tesis. En los Capítulos 3 y 4 se describe la reactividad de sustratos lineales aleno-eno/yno-aleno en forma aquiral o quiral en la reacción totalmente intramolecular de la cicloadición [2+2+2] catalizada por rodio(I). El Capítulo 5 desarrolla una reacción de cicloadición [2+2+2] deshidrogenativa de sustratos ciano-yno-aleno que permite la síntesis de la unidad estructural de 2,6-naftiridina presente en distintos productos biológicamente relevantes. El Capítulo 6 incluye las conclusiones generales que se extraen de la tesis. Por último, el Capítulo 7 contiene el procedimiento experimental y la caracterización de todos los compuestos sintetizados en esta tesis.
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Parera, Briansó Magda. "Transition metal-catalysed [2+2+2] cycloaddition reactions. Methodology and mechanism." Doctoral thesis, Universitat de Girona, 2014. http://hdl.handle.net/10803/145035.

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The transition-metal catalysed [2+2+2] cycloaddition reaction is a highly efficient synthetic tool that allows six-membered polysubstituted carbo- and heterocyclic derivatives to be obtained in an atom economy process. This doctoral thesis is based on methodological and mechanistic studies of the rhodium(I)-catalysed [2+2+2] cycloaddition reaction. In particular, the use of hemilabile S-stereogenic and P-stereogenic ligands for the rhodium-catalysed [2+2+2] cycloaddition is described. The activity of these new catalytic systems is evaluated in the cycloaddition of three alkynes and in the enantioselective cycloaddition of enediynes to obtain chiral cyclohexa-1,3-dienes. Moreover, the participation of Baylis-Hillman adducts as alkene moieties for the partially intramolecular [2+2+2] cycloaddition is described for the synthesis of a set of enantioenriched bicyclic cyclohexadienes featuring a quaternary stereogenic centre. Finally, the mechanistic study of the [2+2+2] cycloaddition of alkynes by electrospray ionization mass spectrometry and DFT calculations is performed.
La reacció de cicloaddició [2+2+2] catalitzada per metalls de transició és una eina molt eficient que permet la formació de derivats carbo- i heterocíclics polisubstituïts de sis membres en un procés d’economia atòmica. Aquesta tesi doctoral es basa en l’estudi metodològic i mecanístic de les reaccions de cicloaddició [2+2+2] catalitzades per rodi(I). Concretament, es descriu l’ús de lligands hemilàbils S-estereogènics i P-estereògenics per a la reacció de cicloaddició [2+2+2] catalitzada per rodi d’alquins i també en la cicloaddició enantioselectiva d’endiïns per a l’obtenció de ciclohexadiens quirals. També s’estudia la participació d’adductes de Baylis-Hillman com a substrats olefínics d’aquestes reaccions permetent la síntesi de ciclohexadiens quirals bicíclics amb un centre estereogènic quaternari. Finalment, es presenta l’estudi mecanístic de les reaccions de cicloaddició [2+2+2] d’alquins a través de l’espectrometria de masses amb ionització per electroesprai i càlculs DFT.
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Fernández, Wang Martí. "New challenges in Rh(I)-catalysed [2+2+2] cycloaddition reactions." Doctoral thesis, Universitat de Girona, 2017. http://hdl.handle.net/10803/663661.

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This doctoral thesis studies the involvement of challenging unsaturated substrates in the transition-metal catalysed [2+2+2] cycloaddition reaction, as well as new catalytic systems for the reaction. First, Morita-Baylis-Hillman adducts are involved in the partial intramolecular rhodium(I)-catalysed [2+2+2] cycloaddition reaction. Next, linear chiral allene-yne/ene-allene substrates are synthesized and submitted to [2+2+2] cycloaddition reaction conditions. The process works with effective chirality induction of the chiral centres of the linear compounds to the cycloadducts. Following, the synthesis of a dendrimer by means of a Co-catalysed [2+2+2] cycloaddition reaction to form the core is described. The dendrimer contains a poly(ethylene glycol) moiety, as well as a ligand that can coordinate to a metal. Finally, hybrid silica materials containing rhodium(I) complexes are prepared. These materials are used for the [2+2+2] cycloaddition of alkynes and can be recovered by simple filtration and reused in further reactions.
Aquesta tesi doctoral estudia la participació de substrats insaturats complexos en la reacció de cicloaddició [2+2+2] catalitzada per metall de transició, així com nous sistemes catalítics per la reacció. Primer s'utilitzen adductes de Morita-Baylis-Hillman en la reacció de cicloaddició [2+2+2] catalitzada per rodi(I) parcialment intramolecular. Després, es sintetitzen substrats lineals al·lè-í/è-al·lè quirals i es sotmeten a condicions de cicloaddició [2+2+2]. El procés dóna lloc a una inducció quiral dels centres quirals dels compostos lineals cap els cicloadductes. A continuació, es descriu la síntesi d'un dendrimer mitjançant una cicloaddició [2+2+2] catalitzada per cobalt per formar el cor. El dendrimer conté un residu de polietilé glicol, així com un lligand que pot coordinar a un metall. Finalment, es preparen síliques híbrides que contenen complexos de rodi(I). Aquests materials s'utilitzen en la cicloaddició [2+2+2] d'alquins i es poden recuperar per simple filtració i reutilitzar en pròximes reaccions.
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Dachs, Soler Anna. "Rhodium(I) catalyzed [2+2+2] cycloaddition reactions: experimental and theoretical studies." Doctoral thesis, Universitat de Girona, 2011. http://hdl.handle.net/10803/52981.

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The [2+2+2] cycloaddition reaction involves the formation of three carbon-carbon bonds in one single step using alkynes, alkenes, nitriles, carbonyls and other unsaturated reagents as reactants. This is one of the most elegant methods for the construction of polycyclic aromatic compounds and heteroaromatic, which have important academic and industrial uses. The thesis is divided into ten chapters including six related publications. The first study based on the Wilkinson’s catalyst, RhCl(PPh3)3, compares the reaction mechanism of the [2+2+2] cycloaddition process of acetylene with the cycloaddition obtained for the model of the complex, RhCl(PH3)3. In an attempt to reduce computational costs in DFT studies, this research project aimed to substitute PPh3 ligands for PH3, despite the electronic and steric effects produced by PPh3 ligands being significantly different to those created by PH3 ones. In this first study, detailed theoretical calculations were performed to determine the reaction mechanism of the two complexes. Despite some differences being detected, it was found that modelling PPh3 by PH3 in the catalyst helps to reduce the computational cost significantly while at the same time providing qualitatively acceptable results. Taking into account the results obtained in this earlier study, the model of the Wilkinson’s catalyst, RhCl(PH3)3, was applied to study different [2+2+2] cycloaddition reactions with unsaturated systems conducted in the laboratory. Our research group found that in the case of totally closed systems, specifically 15- and 25-membered azamacrocycles can afford benzenic compounds, except in the case of 20-membered azamacrocycle (20-MAA) which was inactive with the Wilkinson’s catalyst. In this study, theoretical calculations allowed to determine the origin of the different reactivity of the 20-MAA, where it was found that the activation barrier of the oxidative addition of two alkynes is higher than those obtained for the 15- and 25-membered macrocycles. This barrier was attributed primarily to the interaction energy, which corresponds to the energy that is released when the two deformed reagents interact in the transition state. The main factor that helped to provide an explanation to the different reactivity observed was that the 20-MAA had a more stable and delocalized HOMO orbital in the oxidative addition step. Moreover, we observed that the formation of a strained ten-membered ring during the cycloaddition of 20-MAA presents significant steric hindrance. Furthermore, in Chapter 5, an electrochemical study is presented in collaboration with Prof. Anny Jutand from Paris. This work allowed studying the main steps of the catalytic cycle of the [2+2+2] cycloaddition reaction between diynes with a monoalkyne. First kinetic data were obtained of the [2+2+2] cycloaddition process catalyzed by the Wilkinson’s catalyst, where it was observed that the rate-determining step of the reaction can change depending on the structure of the starting reagents. In the case of the [2+2+2] cycloaddition reaction involving two alkynes and one alkene in the same molecule (enediynes), it is well known that the oxidative coupling may occur between two alkynes giving the corresponding metallacyclopentadiene, or between one alkyne and the alkene affording the metallacyclopentene complex. Wilkinson’s model was used in DFT calculations to analyze the different factors that may influence in the reaction mechanism. Here it was observed that the cyclic enediynes always prefer the oxidative coupling between two alkynes moieties, while the acyclic cases have different preferences depending on the linker and the substituents used in the alkynes. Moreover, the Wilkinson’s model was used to explain the experimental results achieved in Chapter 7 where the [2+2+2] cycloaddition reaction of enediynes is studied varying the position of the double bond in the starting reagent. It was observed that enediynes type yne-ene-yne preferred the standard [2+2+2] cycloaddition reaction, while enediynes type yne-yne-ene suffered β-hydride elimination followed a reductive elimination of Wilkinson’s catalyst giving cyclohexadiene compounds, which are isomers from those that would be obtained through standard [2+2+2] cycloaddition reactions. Finally, the last chapter of this thesis is based on the use of DFT calculations to determine the reaction mechanism when the macrocycles are treated with transition metals that are inactive to the [2+2+2] cycloaddition reaction, but which are thermally active leading to new polycyclic compounds. Thus, a domino process was described combining an ene reaction and a Diels-Alder cycloaddition.
La reacció de cicloaddició consisteix en la formació de tres enllaços carboni-carboni en un únic pas de reacció on poden estar involucrats alquins, alquens, nitrils, carbonils i altres compostos insaturats. És un dels mètodes més elegants per a la construcció de compostos aromàtics i heteroaromatics policíclics amb importants usos acadèmics i industrials. La tesi es divideix en deu capítols que contenen sis publicacions relacionades. El primer estudi es basa en el catalitzador de Wilkinson, RhCl(PPh3)3, on es compara el mecanisme de reacció del procés de cicloaddició d’acetilè pel que s’obté amb el model del complex, RhCl(PH3)3. Aquest projecte de recerca va ser iniciat per estudiar la substitució de lligands PPh3 per PH3 en els estudis de DFT, que s’aplica habitualment per reduir el cost computacional, tot i que els efectes electrònics i estèrics produïts pels lligands PPh3 són molt diferents dels creats per PH3. Malgrat algunes diferències observades, es va constatar que la substitució de PPh3 per PH3 en el catalitzador pot ser utilitzada per reduir el cost computacional de manera significativa i a l’hora obtenir resultats qualitativament acceptables. Un cop obtinguts els resultats anteriors, es va utilitzar el model del catalitzador de Wilkinson, RhCl(PH3)3, per l’estudi teòric de diferents reaccions de cicloaddició amb sistemes insaturats duts a terme al laboratori. En el grup de recerca es va trobar que en el cas de sistemes totalment tancats, concretament els macrocicles de 15 i 25 baules, poden donar sistemes benzènics policíclics excepte en el cas del macrocicle de 20 baules, que va resultar inactiu vers el catalitzador de Wilkinson. En aquest estudi, la realització de càlculs teòrics va permetre determinar l’origen de la diferent reactivitat del macrocicle de 20 baules, on es va trobar que la barrera d’activació de l’addició oxidativa entre dos alquins és molt més alta que les que es van obtenir pel macrocicle de 15 i 25 baules. Aquesta barrera es va atribuir bàsicament a l’energia d’interacció, la qual correspon a l’energia que s’allibera quan els dos reactius deformats interaccionen en l’estat de transició. Concretament el principal factor que hi contribueix és que el macrocicle de 20 baules presenta més estabilitat i més deslocalització de l’orbital HOMO en el pas d’addició oxidativa. A més a més, es va observar que la formació d’anells de 10 baules durant la cicloaddició del macrocicle de 20 baules presenta impediments estèrics importants. Per altra banda, en el Capítol 5 es presenten estudis electroquímics realitzats en col•laboració amb la Prof. Anny Jutand de París, que van permetre estudiar el cicle catalític de la reacció de cicloadició entre un dií i un monoalquí. Es van obtenir així les primeres dades cinètiques dels dos principals passos del cicle catalític amb el complex de Wilkinson, on es va observar que el pas determinant de la reacció pot variar en funció de l’estructura dels reactius de partida. En el cas en què en la reacció de cicloaddició participin dos triples i un doble enllaç en la mateixa molècula (endiins), és conegut que l’addició oxidativa pot donar-se entre dos triples enllaços o un triple i un doble enllaç. El model del catalitzador de Wilkinson va ser utilitzat mitjançant càlculs DFT per analitzar els diferents factors que poden influir en el mecanisme de reacció. Aquí es va observar que els endiins cíclics sempre prefereixen l’addició oxidativa entre els dos triples enllaços, mentre que els acíclics tenen diferent preferència en funció del linker i dels substituents presents en els triples enllaços. A més a més, el mateix model de Wilkinson es va utilitzar per explicar els resultats experimentals realitzats en el Capítol 7 on s’estudia la reacció de cicloaddició d’endiins variant la posició del doble enllaç en el reactiu de partida. Es va observar que els sistemes in-en-in preferien la cicloaddició convencional donant el producte ciclohexadienic esperat, mentre que els sistemes in-in-en patien una β-eliminació seguida d’una eliminació reductiva del catalitzador de Wilkinson i donant, finalment, productes ciclohexadiènics els quals són isòmers dels que s’obtindrien mitjançant una cicloaddició convencional. Finalment, l’últim capítol d’aquesta tesi es basa en l’ús de càlculs DFT per determinar el mecanisme de reacció quan els macrocicles són tractats amb metalls de transició inactius per donar la reacció de cicloaddició, però reaccionen tèrmicament obtenint nous compostos policíclics. Així es va descriure un procés dòmino on es combina una reacció ene seguida d’una cicloaddició de Diels-Alder.
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Allart, Eric A. "Metal-promoted [3+2] and [4+2] cycloaddition reactions." Thesis, Loughborough University, 2008. https://dspace.lboro.ac.uk/2134/33615.

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Dicobalt complexes have been extensively used in synthetic chemistry to protect triple bonds, to form new carbon/carbon bonds using the Nicholas reaction and to form polycyclic molecules using the Pauson-Khand reaction. Using these dicobalt complexes, the formation of new carbon-heteroatom bonds was developed through [3+2] and [4+2] cycloaddition reactions via a stabilised dipole intermediate. Initial work carried out makes use of cyclopropanes substituted with a metal-alkyne complex towards the synthesis of tetrahydrofurans and pyrrolidines in good yields and with acceptable diastereoselectivity. The initial aim of the work described hereafter was to improve and expand the previous work carried out within the group. An alternative route using dihydrofurans as a cyclopropane surrogate was explored as well as other methods to form the cyclopropane in a-position to the alkyne. To extend the scope of the methodology, [4+2] cycloaddition reactions have been explored, using Nicholas carbocation. Various precursors have been prepared using a Knoevenagel condensation or an ene reaction. For the first time in synthetic chemistry, a novel [4+2] dipolar cycloaddition reaction from a cyclobutane has been developed. This reaction has opened a new way for the synthesis of six-membered heterocycles in a totally diastereoselective fashion using cyclobutane cores as precursors. A wide range of aldehydes was used as trapping reagents to form tetrahydropyrans in good yields up to 95% and with a good to total diastereoselectivity proven by nOe and X-Ray analyses. The use of other reagents such as ketones, imines and alkenes has been investigated· towards the formation of new six-membered rings as an extension of the methodology.
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Garcia, Pierre. "Formation d'aminopyridines par cycloaddition [2+2+2] catalysée par des complexes du cobalt." Paris 6, 2013. http://www.theses.fr/2010PA066750.

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姚大源 and Tai-yuen Yue. "Cycloaddition reactions of 2-vinylchromones." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1992. http://hub.hku.hk/bib/B31210661.

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LLERENA, DOMINIQUE. "Reactions de cycloaddition (2+2+2) d'allenediynes catalysees par des complexes du cobalt (i)." Paris 6, 1995. http://www.theses.fr/1995PA066378.

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Des allenediynes diversement substitues, dont les syntheses originales sont decrites ont ete engages avec des quantites stoechiometriques de cpco(co)#2 dans des reactions de cycloaddition (2+2+2). Ces reactions ont permis la synthese de structures tricycliques analogues des cycles abc ou bcd de steroides. Par ailleurs, cette etude a permis de mettre en evidence une nouvelle catalyse de la ene-reaction par le cobalt mettant en jeu des composes allenynes
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Selva, Verónica. "Diastereoselective multicomponent [3+2] and [4+2] cycloadditions." Doctoral thesis, Universidad de Alicante, 2018. http://hdl.handle.net/10045/77573.

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En esta tesis doctoral se ha estudiado los iluros de azometino generados in situ en reacciones de cicloadición 1,3-dipolar y diferentes dipolarófilos para la síntesis multicomponente (libre de metales) de derivados de indolizidina a partir de pipecolinatos, aldehídos y dipolarofilos de forma térmica, y también a partir de ácido pipecólico de forma descarboxilada. También se ha estudiado la reacción de cicloadición 1,3-dipolar térmica multicomponente entre iluros de azometino no activados generados in situ a partir de aminas, aldehídos aromáticos y alquenos electrofílicos para generar derivados de pirrolidina.Además, se describe la síntesis de pirrolizidinas diastereoméricamente enriquecidas a partir de nitroprolinatos enantioméricamente puros a través de una cicloadición 1,3- dipolar multicomponente catalizada por una sal de plata y, por otro lado, una reacción de Amina-Aldehído-Dienófilo (AAD) para sintetizar estructuras ciclohex-2-en-1-ilprolinato como diastereoisómero enantiopuro único de forma multicomponente y libre de metales.
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Libros sobre el tema "[2+2+2] cycloaddition"

1

Davidson, Tony. Studies in the cobalt catalyzed [2+2+2+2] cycloaddition and deprotonation of dicobalt hexacarbonyl-acetylene complexes. National Library of Canada, 1990.

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Joseph Johannes Gerardus Steven van Es. 1, 3-cycloaddition reactions of diphenylphosphinoyl-activated azomethine ylides and 2-azaallyl anions: Synthetic applications and mechanistic aspects. Pasmans Offsetdrukkerij BV, 1992.

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Watanabe, Junʾichi. Hong 2/2. Cosmos, 1999.

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Domon, Fujuji. Uesugi 2/2. Gakuyo Shobo, 1992.

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Dmitriev, Oleg. 2-Obshchezhitie-2. Molodai︠a︡ gvardii︠a︡, 1988.

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Akagawa, Jirō. Wen 2/2. Zheng Wen, 2003.

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Denisov, Ėdison Vasilʹevich. Oktett für 2 Oboen, 2 Klarinetten, 2 Fagotte und 2 Hörner. H. Sikorski, 1991.

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Kagaku Busshitsu Hyōka Kenkyū Kikō and Shin Enerugī Sangyō Gijutsu Sōgō Kaihatsu Kikō (Japan), eds. 2-imidazorijinchion: 2-imidazolidinethione. Seihin Hyōka Gijutsu Kiban Kikō Kagaku Busshitsu Hyōka Kenkyū Kikō, 2009.

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Claude, Mutafian, ed. Erkir 2: Yergir 2. H.H. Khatcherian, 2011.

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Yoshimura, Tatsuya. Shou ji 2/2. Zheng Wen, 2002.

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Capítulos de libros sobre el tema "[2+2+2] cycloaddition"

1

Laue, Thomas, and Andreas Plagens. "[2+2] Cycloaddition." In Teubner Studienbücher Chemie. Vieweg+Teubner Verlag, 1994. http://dx.doi.org/10.1007/978-3-322-94015-5_28.

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Laue, Thomas, and Andreas Plagens. "[2+2]Cycloaddition." In Teubner Studienbücher Chemie. Vieweg+Teubner Verlag, 1998. http://dx.doi.org/10.1007/978-3-322-94077-3_29.

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Laue, Thomas, and Andreas Plagens. "[2+2]Cycloaddition." In Teubner Studienbücher Chemie. Vieweg+Teubner Verlag, 1994. http://dx.doi.org/10.1007/978-3-322-94726-0_28.

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Hayashi, Yujiro, and Koichi Narasaka. "[2+2] Cycloaddition Reactions." In Comprehensive Asymmetric Catalysis I–III. Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/978-3-642-58571-5_10.

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Halevi, E. Amitai. "Cycloadditions and Cycloreversions I. [2+2]-Cycloaddition." In Orbital Symmetry and Reaction Mechanism. Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-83568-1_6.

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Gandon, Vincent. "Cobalt-Mediated [2 + 2 + 2] Cycloaddition." In Transition-Metal-Mediated Aromatic Ring Construction. John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118629871.ch1.

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Kumar, Puneet, and Janis Louie. "Nickel-Mediated [2 + 2 + 2] Cycloaddition." In Transition-Metal-Mediated Aromatic Ring Construction. John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118629871.ch2.

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Yamamoto, Yoshihiko. "Ruthenium-Mediated [2 + 2 + 2] Cycloaddition." In Transition-Metal-Mediated Aromatic Ring Construction. John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118629871.ch3.

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Tanaka, Ken. "Rhodium-Mediated [2 + 2 + 2] Cycloaddition." In Transition-Metal-Mediated Aromatic Ring Construction. John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118629871.ch4.

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Takeuchi, Ryo. "Iridium-Mediated [2 + 2 + 2] Cycloaddition." In Transition-Metal-Mediated Aromatic Ring Construction. John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118629871.ch5.

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Actas de conferencias sobre el tema "[2+2+2] cycloaddition"

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Gómez- Campillos, Gonzalo, Cristina Aragoncillo, Pedro Almendros, and Benito Alcaide. "Pd−Catalyzed Domino Alkyne Dimerization/Double [2+2] Allenyne Cycloaddition." In The 13th International Electronic Conference on Synthetic Organic Chemistry. MDPI, 2009. http://dx.doi.org/10.3390/ecsoc-13-00252.

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Förster, Nadja, Ann-Christin Pöppler, and Philipp Vana. "UV-induced [2+2]-cycloaddition for shell-formation of star polymers." In 6TH INTERNATIONAL CONFERENCE ON TIMES OF POLYMERS (TOP) AND COMPOSITES. AIP, 2012. http://dx.doi.org/10.1063/1.4738496.

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Mancini, Pedro, Claudia Della Rosa, and Maria Kneeteman. "Behaviour of 2-nitroheterocycles in Cycloaddition Reactions." In The 9th International Electronic Conference on Synthetic Organic Chemistry. MDPI, 2005. http://dx.doi.org/10.3390/ecsoc-9-01477.

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Montero-Campillo, M., Jesús Rodríguez-Otero, and Enrique Cabaleiro-Lago. "Selectivity of the Ru(II)-Catalyzed [2+2+2] Cycloaddition of 1,6-Diynes and Tricarbonyl Compounds." In The 12th International Electronic Conference on Synthetic Organic Chemistry. MDPI, 2008. http://dx.doi.org/10.3390/ecsoc-12-01286.

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Rajzmann, Michel, Agnés Pommier, Jean-Marc Pons, Philippe Thomas, and André Baldy. "A semiempirical theoretical study of the [2+2] cycloaddition between ketene and formaldehyde." In The first European conference on computational chemistry (E.C.C.C.1). AIP, 1995. http://dx.doi.org/10.1063/1.47652.

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Yi, Jun, Junpeng Wang, and Zhou Lin. "MECHANISTIC STUDY OF PHOTOCHEMICAL [2+2] CYCLOADDITION BETWEEN 1,5-CYCLOOCTADIENE AND MALEIC ANHYDRIDE." In 2022 International Symposium on Molecular Spectroscopy. University of Illinois at Urbana-Champaign, 2022. http://dx.doi.org/10.15278/isms.2022.rh11.

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Montero­Campillo, M., Enrique Cabaleiro­Lago, and Jesús Rodríguez­Otero. "On the Mechanism of Rhodium-Catalyzed [6+2] Cycloaddition of 2-Vinylcylobutanones and Alknenes." In The 11th International Electronic Conference on Synthetic Organic Chemistry. MDPI, 2007. http://dx.doi.org/10.3390/ecsoc-11-01369.

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Sheradsky, Tuvia, and Elliad Silcoff. "The Synthesis of (2R,5R)-2-Amino-5-Hydroxyhexanoic Acid by Intermolecular Cycloaddition." In The 1st International Electronic Conference on Synthetic Organic Chemistry. MDPI, 1997. http://dx.doi.org/10.3390/ecsoc-1-02026.

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Ramasami, Ponnadurai, Hanusha Bhakhoa, and Lydia Rhyman. "Copper(I) Catalyzed [3+2] Cycloaddition Reaction with Mechanistic Disparity: A DFT Study." In The 17th International Electronic Conference on Synthetic Organic Chemistry. MDPI, 2013. http://dx.doi.org/10.3390/ecsoc-17-e017.

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Barcellos, Júlio C. F., Ayres G.Dias, and Paulo R. R.Costa. "Synthesis of Azapterocarpan Analogues by Intramolecular 1,3-dipolar Cycloaddition." In 14th Brazilian Meeting on Organic Synthesis. Editora Edgard Blücher, 2013. http://dx.doi.org/10.5151/chempro-14bmos-r0090-2.

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Informes sobre el tema "[2+2+2] cycloaddition"

1

Hunn, John D., Robert Noel Morris, Charles A. Baldwin, and Fred C. Montgomery. Safety Testing of AGR-2 UCO Compacts 5-2-2, 2-2-2, and 5-4-1. Office of Scientific and Technical Information (OSTI), 2016. http://dx.doi.org/10.2172/1328314.

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Hunn, John, Will Cureton, Darren Skitt, and Fred Montgomery. SAFETY TESTING OF AGR-5/6/7 COMPACTS 2-2-2 AND 2-2-4. Office of Scientific and Technical Information (OSTI), 2022. http://dx.doi.org/10.2172/1887660.

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Hunn, John D., Fred C. Montgomery, Tamara {Tammy} Jo Keever, Benjamin Roach, and Ralph Ilgner. Determination of Average Burnup in AGR-2 Compacts 3-3-1, 3-3-2, 2-2-2, and 6-4-2. Office of Scientific and Technical Information (OSTI), 2019. http://dx.doi.org/10.2172/1569364.

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Kettell, S. H. Measurement of the 2 sup 2 S sub 1/2 -2 sup 2 P sub 3/2 fine structure interval in muonium. Office of Scientific and Technical Information (OSTI), 1990. http://dx.doi.org/10.2172/6849854.

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Montgomery, Fred C., John D. Hunn, Tamara J. Keever, et al. Measurement of Average Burnup in TRISO-Coated Particles from AGR-2 UCO Compacts 2-2-2 and 6-4-2. Office of Scientific and Technical Information (OSTI), 2018. http://dx.doi.org/10.2172/1476419.

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Amornrattanapong, Weeraphat. Malware Analysis Day 2 - Part 2. Office of Scientific and Technical Information (OSTI), 2019. http://dx.doi.org/10.2172/1574734.

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Armstrong, Beth, Lucy King, Robin Clifford, and Mark Jitlal. Food and You 2 - Wave 2. Food Standards Agency, 2021. http://dx.doi.org/10.46756/sci.fsa.dws750.

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Food and You 2 is a biannual survey which measures self-reported consumer knowledge, attitudes and behaviours related to food safety and other food issues amongst adults in England, Wales, and Northern Ireland. The survey is primarily carried out online using a methodology known as ‘push-to-web’. Fieldwork was conducted between 20 November 2020 and 21 January 2021. A total of 5,900 adults from 3,955 households across England, Wales and Northern Ireland completed the survey. Topics covered in the Food and You 2: Wave 2 Key Findings report include: Trust in FSA and the food supply chain Concerns about food Food security Eating out and takeaways Food allergy, intolerance, and other hypersensitivities Food safety in the home
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Hunn, John D., Robert Noel Morris, Charles A. Baldwin, and Fred C. Montgomery. Safety testing of AGR-2 UO2 compacts 3-3-2 and 3-4-2. Office of Scientific and Technical Information (OSTI), 2015. http://dx.doi.org/10.2172/1222564.

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Hunn, John, Robert Morris, and Charles Baldwin. Safety Tests on Irradiated AGR-1 Compacts 3-3-2, 3-2-2, and 6-2-1. Office of Scientific and Technical Information (OSTI), 2012. http://dx.doi.org/10.2172/1649218.

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Belshe, M., and R. Peon. Hypertext Transfer Protocol Version 2 (HTTP/2). Edited by M. Thomson. RFC Editor, 2015. http://dx.doi.org/10.17487/rfc7540.

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