Дисертації: "4+2 diene"

1

Williams, Julian Outfin. "An investigation of the synthetic potential of cyclohexa-3,5-diene-cis-1,2-diol and some related compounds with special reference to [4 + 2] and [2 + 2] cycloaddition reactions." Thesis, University of Exeter, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.305838.

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2

Köhler, Frank. "Synthese von Bi-2H-azirin-2-ylen und deren Valenzisomerisierung zu Diazinen." Doctoral thesis, Universitätsbibliothek Chemnitz, 2002. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-200200926.

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In der vorliegenden Arbeit wird die Darstellung von Verbindungen mit offenkettiger 1,4-Diazidobuta-1,3-dien-Substruktur beschrieben. Die Synthese dieser neuartigen Verbindungen ist durch Substitutionsreaktion an geeigneten Dihalogen-Vorstufen und durch elektrocyclische Ringöffnung der bisher ebenfalls unbekannten 3,4-Diazidocyclobutene möglich. Die 1,4-Diazidobuta-1,3-diene dienten als Vorläufer zur photochemischen bzw. thermischen Darstellung von Bi-2H-azirin-2-ylen. Einen Schwerpunkt der Arbeit bildeten die Untersuchungen zur Valenzisomerisierung dieser Verbindungen.

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3

Chreim, Yamama. "Synthese de polymeres organosilicies par polycondensation de dienes polycycliques." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13134.

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Polycondensation de molecules diinsaturees, mono- ou polycycliques avec des molecules disilylees (hydrosilylation des doubles liaisons par des fonctions si-h. Les polymeres ont des masses moleculaires comprises entre 3000 et 25000. Stabilite thermique jusqu'a 450**(o)c

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4

Pingali, Aparna. "Synthesis and X-ray Diffraction Structures of 2-(2-thienylidene)-4,5-bis-(diphenylphosphino)-4-cyclopenten-1,3-dione and fac-BrRe(CO)3[2-(2-thienylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione]." Thesis, University of North Texas, 2005. https://digital.library.unt.edu/ark:/67531/metadc4942/.

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Treatment of 4,5 bis-(diphenylphosphino)-cyclopenten-1,3 dione with thiophene carboxyaldehyde in dichloromethane, in the presence of molecular sieves results in a new heterocyclic compound, 2-(2-thienylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (ligand), with a high yield. This product was characterized by using both IR and NMR spectroscopic techniques and the solid-state structure of the ligand was determined using X-ray crystallography. When the ligand was treated with the solvent stabilized intermediate of ReBr(CO)5 with THF, a monomeric metal complex, fac-BrRe(CO)3[2-(2-thienylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione] was the result. The solid-state structure of the monomeric metal complex was determined using X-ray crystallography. Photolysis and thermolysis studies of the complex will be further explored.

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5

Melzer, Antje. "Vinylazide - Synthesen und Reaktionen." Doctoral thesis, [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=968777910.

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6

Hunt, Sean W. Richmond Michael G. "Synthesis and characterization of platinum(II)(2-(9-anthracenylylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione)(dichloride), platinum(II)(2-(9-anthracenylylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione(maleonitriledithiolate), and platinum(II)(4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione)(4-methyl-1,2-benzene dithiol)." [Denton, Tex.] : University of North Texas, 2009. http://digital.library.unt.edu/ark:/67531/metadc12135.

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7

Hunt, Sean W. "Synthesis and Characterization of Platinum(II)(2-(9-anthracenylylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione)(dichloride), Platinum(II)(2-(9-anthracenylylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione(maleonitriledithiolate), and Platinum(II)(4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione)(4-Methyl-1,2-benzene dithiol)." Thesis, University of North Texas, 2009. https://digital.library.unt.edu/ark:/67531/metadc12135/.

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Substitution of the 1,5-cyclooctadiene (cod) ligand in PtCl2(cod) (1) by the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) yields PtCl2(bpcd) (2). Knoevenagel condensation of 2 with 9-anthracenecarboxaldehyde leads to the functionalization of the bpcd ligand and formation of the corresponding 2-(9-anthracenylidene)-4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (abpcd) substituted compound PtCl2(abpcd) (3), which is also obtained from the direct reaction of 1 with the abpcd ligand in near quantitative yield. The reaction of 3 with disodium maleonitriledithiolate (Na2mnt) affords the chelating dithiolate compound Pt(mnt)(abpcd) (4). The reaction of PtCl2(bpcd) (2) with 4-methyl-1,2-benzene dithiol under basic conditions affords Pt(tdt)(bpcd) (5). Compounds 2-5 have been fully characterized in solution by IR and NMR spectroscopies (1H and 31P), and their molecular structures established by X-ray crystallography. The electrochemical properties of 2‑5 have examined by cyclic voltammetry, and the nature of the HOMO and LUMO levels in systems 2-4 has been established by MO calculations at the extended Hückel level, the results of which are discussed with respect to electrochemical data and related diphosphine derivatives. In addition the new compounds 2-5 have been isolated by column chromatography and characterized by IR, UV-Vis spectroscopy.

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8

Souza, Severino Araújo de. "Estudos químicos e biológicos de compostos heterocíclicos derivados dos núcleos imidazolidina-2,4-diona e 2-tioxoimidazolidina-4-ona." Universidade Federal da Paraíba, 2015. http://tede.biblioteca.ufpb.br:8080/handle/tede/9023.

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The breakthrough occurred in the scientific world involving chemical and pharmacological studies of heterocyclic are the result of the large investment from pharmaceutical companies and research centers in universities. Synthetic Heterocyclic compounds stand out because of the possibilities these compounds present several different biological properties. Structural changes in imidazolidínico and tioimidazolidínico rings can change their chemical, physical properties and produce biological effects with a variety of useful applications. The objective of this work was the synthesis and characterization of heterocyclic compounds of imidazolidine-2,4-dione class and 2-thioxo-imidazolidine-4-one in order to investigate their pharmacological potential as antimicrobial, antinociceptive, anti-tumor and anticonvulsant and study their thermal stability. The compounds were obtained in two steps: first, reacted sodium cyanide, ammonium chloride, methylammonium chloride, isopropylammonium chloride and substituted aromatic aldehydes to, followed by acid hydrolysis to form the amino acid derivatives of glycine. In the second stage, there was the reaction of amino acids prepared with potassium isocyanate and ammonium isothiocyanate and / or phenyl isocyanate and / or phenyl isothiocyanate followed by acid hydrolysis to form the imidazolidínicos derivatives: IM-15; HPA-05; HPA-09; HPA-10; HPA-14; HPA-15A; HPA-15B; HPA-15C; HPA-15D; HPA-15E; HPA-15F; HPA-15G; HPA-15H; HPA-15J and tioimidazolidínicos: HPA-03; HPA-04; HPA-08; HPA-11; HPA-15I; HPA-15M. The structures of the synthesized compounds were characterized by IR absorption spectroscopy, 1H-NMR and 13C-NMR. With the synthesized compounds investigated the potential front Antimicrobial studies, antinociceptive, anticarcinogenic and CNS. Also evaluated the thermal stability of the synthesized compounds and in silico studies.
O grande avanço ocorrido no mundo científico envolvendo os estudos químicos e farmacológicos de heterocíclicos são frutos do grande investimento das indústrias farmacêuticas e dos centros de pesquisas nas universidades. Os compostos heterocíclicos sintéticos se destacam devido às possibilidades existentes nesses compostos de apresentar várias propriedades biológicas diferentes. Modificações estruturais nos anéis imidazolidínico e tioimidazolidínico podem alterar suas propriedades químicas, físicas e produzir efeitos biológicos com uma grande variedade de aplicações úteis. O objetivo desse trabalho foi a síntese e caracterização de compostos heterocíclicos da classe imidazolidina-2,4-diona e 2-tioxo-imidazolidina-4-ona com a finalidade de investigar suas potencialidades farmacológicas como antimicrobianos, antinociceptivos, antitumoral e anticonvulsivante e estudar sua estabilidade térmica. Os compostos foram obtidos em duas etapas: na primeira, fez-se reagir cianeto de sódio, cloreto de amônio, cloreto de metilamônio, cloreto de isopropilamônio e aldeídos aromáticos para substituídos, seguido de hidrólise ácida para a formação dos aminoácidos derivados da glicina. Na segunda etapa, fez-se a reação dos aminoácidos preparados com isocianato de potássio e isotiocianato de amônio e/ou fenilisocianato e/ou fenilisotiocianato seguido de hidrólise ácida formando os derivados imidazolidínicos: IM-15; HPA-05; HPA-09; HPA-10; HPA-14; HPA-15A; HPA-15B; HPA-15C; HPA-15D; HPA-15E; HPA-15F; HPA-15G; HPA-15H; HPA-15J e tioimidazolidínicos: HPA-03; HPA-04; HPA-08; HPA-11; HPA-15I; HPA-15M. As estruturas dos compostos sintetizados foram caracterizadas através da espectroscopia de absorção no IV, de RMN de 1H e RMN de 13C. Com os compostos sintetizados investigou a potencialidade frente aos estudos Antimicrobianos, Antinociceptivos, Anticarcinogênico e sobre o SNC. Avaliou também a estabilidade térmica dos compostos sintetizados e os estudos in silico.

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9

Hayes, Patricia. "Premiers exemples d'heterocycloadditions 4 + 2 intermoleculaires de 3-sulfinyloxabuta-1,3-dienes chiraux application a la synthese de pheromones acetaliques." Le Mans, 1998. http://www.theses.fr/1998LEMA1002.

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Cette these est une contribution a la mise au point de nouvelles methodologies de synthese diastereoselectives utilisant un sulfoxyde comme vecteur de chiralite. D'une part, une methode originale de dedoublement du p-tolylvinylsulfoxyde racemique a ete mise au point, utilisant une reaction tandem addition-elimination d'un alcool chiral. Elle a permis un acces simple et plus rapide aux deux antipodes enantiopurs du vinylsulfoxyde par rapport aux syntheses existantes. D'autre part, des 3-sulfinyloxabuta-1,3-dienes racemiques et optiquement actifs, differemment substitues, ont ete synthetises selon plusieurs schemas reactionnels tels que l'oxydation d'alcools allyliques ou de sulfures prochiraux. La reactivite de ces sulfinylheterodienes a ete etudiee dans des cycloadditions 4 + 2 a demande electronique inverse. Les resultats obtenus mettent en evidence la tres grande reactivite de ce type d'oxabutadienes dans des conditions tres douces et sans catalyseur. Ces reactions interviennent avec une excellente selectivite endo mais des selectivites diastereofaciales generalement modestes sont observees sauf dans le cas de dienophiles styreniques conduisant a des reactions totalement diastereoselectives. Enfin, une approche de la synthese totale de pheromones d'insectes de structure spiroacetalique ou acetal bicyclique a ete abordee. Cette etude a permis de synthetiser, en deux etapes, des derives spiroacetaliques instaures optiquement actifs avec de bons exces enantiomeriques ainsi que des acetals bicycliques et tricycliques par des additions conjuguees intramoleculaires, activees par le groupement sulfinyle. Ce travail de these decrit les premiers exemples d'heterocycloadditions intermoleculaires mettant en jeu des sulfinyloxabutadienes chiraux et offre donc un nouveau champ d'investigation du groupement sulfinyle en tant qu'auxiliaire chiral porte par un heterodiene.

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10

Tang, Yongping. "Investigation of the stereochemistry of macrocyclic ligand complexes: [Ni(tetramethylcyclam)][superscript]2+ and [brace]Co(Me[subscript]6[14]dieneN[subscript]4)CI[subscript]2+[brace]." Thesis, Georgia Institute of Technology, 1990. http://hdl.handle.net/1853/26951.

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11

Fossey, Christine. "Synthèse de nucléosides pyrimidiniques à visée antivirale (anti-sida) possédant un aglycone original : la thiéno (3,2-d) pyrimidine-2, 4-dione." Caen, 1992. http://www.theses.fr/1992CAEN4047.

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12

COLSON, PIERRE-JEAN. "Des acyl-1 et acyl-2 dienes fer-tricarbonyle aux complexes d'epoxydes dieniques. Synthese totale du (5s,6s)-leucotriene lta#4." Université Louis Pasteur (Strasbourg) (1971-2008), 1991. http://www.theses.fr/1991STR13112.

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Ce travail porte sur quelques aspects de la chimie des complexes de dienes acycliques du fer-tricarbonyle. Nous avons developpe une nouvelle voie d'acces a des complexes d'acyl-2-butadiene basee sur le couplage par catalyse au palladium de chlorures d'acides avec des dienes stannyles en position 2. Ces composes ont ete etudies dans les reactions d'aldolisation et dans la transformation fonctionnelle en oxirane. Cette etude nous a permis de developper une methode de synthese de complexes d'oxiranyl-2 butadienes fer-tricarbonyle que nous avons etendue a la preparation de complexes d'oxiranyl-1 dienes fer-tricarbonyle racemiques ou optiquement actifs. Quelques exemples d'ouverture selective de ces composes ont pu etre mis en evidence. Nous avons ensuite applique la methode developpee pour la synthese totale du leucotriene naturel lta#4 (ee>96%) et a son equivalent complexe au fer-tricarbonyle lta#4-fe(co)#3

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13

Shen, Huafeng. "Substitution Chemistry of Ruthenium Clusters with the Diphosphine Ligands: 4,5-Bis(Diphenylphosphino)-4-Cyclo-Penten-1,3-Dione (bpcd), (Z)-Ph₂PCH=CHPP₂ and 3,4-Bis(Diphenylphosphino)-5-Methoxy-2(5H)-Furanone (bmf)." Thesis, University of North Texas, 1997. https://digital.library.unt.edu/ark:/67531/metadc935834/.

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The chemistry of transition metal clusters has been a fast developing area of organometallic research in recent years. Compared to mononuclear metal complexes, polynuclear clusters offer more opportunities to study cooperative effects and electron reservoir properties between contiguous metal centers, in addition to functioning as storehouses for the release of catalytically active small fragments capable of exhibiting heterosite subtrate activation. Theoretically, metal clusters are intermediates between mononuclear complexes and metal surfaces, i.e., they serve as a bridge between molecular and solid-state chemistry. Transition metal clusters are ideal candidates to study M-M interactions stretching from the single bond to the collective metallic behavior found in a three-dimensional network of metal atoms. The reaction between the redox-active diphoshpine ligand bpcd and RU(CO) has been examined under a variety of conditions. The disubstituted cluster Ru3(CO)10(bpcd)(2) has been synthesized and shown to contain a chealating bpcd ligand, on the basis of IR and 31P NMR data. The cluster 2 (chelating isomer) undergoes cluster fragmentation at ambient temperatures in the dark to give the binuclear compound 3 and Ru3(CO)12, with no evidence for the formation of 4. Both 3 and 4 have been isolated and fully characterized in solution by IR and NMR spectroscopy, and the solid-state structure of each new binuclear compound has been established by X-ray diffraction analysis. Independent experiments reveal that dinuclear 3 is converted to 4 by 366 nm light with a quantum efficiency of .0364.

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14

Gomez, Catherine. "Elaboration de nouveaux inhibiteurs mixtes ECA/ECE pour le traitement de l'hypertension." Phd thesis, Université d'Orléans, 2008. http://tel.archives-ouvertes.fr/tel-00465126.

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Les inhibiteurs mixtes de l'ECE et de l'ECA constituent une classe thérapeutique originale qui intervient dans la régulation de l'hémodynamique, en bloquant en amont la production de puissants vasoconstricteurs tels que l'angiotensine II et l'endothéline-1. Ces deux peptides sont générés, respectivement, grâce à l'enzyme de conversion de l'angiotensine II et de l'endothéline-1. En inhibant leur action, les agents thérapeutiques mixtes récents (1970) prennent ainsi une part importante dans le traitement de l'hypertension. Le premier type d'inhibiteurs porte un groupement phosphoré qui se lie au zinc présent dans le site actif de l'enzyme. Ces composés peptidiques, qui possèdent une certaine stéréochimie, ont été synthétisés via des réactions de substitution, de couplage peptidique et d'hydrogénolyse. Les premiers résultats pharmacologiques montrent que seule une activité vis à vis de l'enzyme de conversion de l'angiotensine est décelée. La seconde partie de ce travail présente la synthèse de dérivés cycliques, constitués de cinq ou six chaînons, et qui assurent une chélation au zinc grâce aux groupements carbonyles. Ces molécules sont obtenues en fonctionnalisant l'acide barbiturique ainsi que l'hydantoïne. Grâce à des réactions d'acylation et d'alkylation notamment, un premier composé final a pu être généré mais son inhibition, testée sur l'ECA, est encore faible et nécessite des modulations pour converger vers une activité mixte.

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15

Xing, Dongxia. "Stereoselective Solid-State NaBH₄ Reduction of 1-Methylpentacyclo[5.4.0.0²,⁶.0³,¹⁰,0⁵,⁹]undecane-8, 11-Dione, Synthesis and Chemistry of Strained Alkenes, and Chemical and Microbial Synthesis of Racemic and Optically Active (S)-4-Hydroxy-2-Cyclohexenone." Thesis, University of North Texas, 1995. https://digital.library.unt.edu/ark:/67531/metadc278368/.

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Part I. Reduction of the 1-methylpentacyclo [5.4.0.0²,⁶.0³,¹⁰,0⁵,⁹]undecane-8, 11-dione (9) with solid NaBH₄ resulted in highly stereoselective reduction of both C=O groups in the substrate, thereby affording the corresponding endo-8, endo-11-diol (11a). The configuration of 11a was established unequivocally by converting 11a into the corresponding cyclic thiocarbonate ester, 12. Part II. Z-1,2-Di(1'-adamantyl)ethene (14) was synthesized with a high degree of stereoselectively in four steps (Scheme 9 in Chapter 2). E-1,2-di(1'-adamantyl)ethene (15) was synthesized by iodine promoted isomerization of 14. Both structures were established unequivocally via single-crystal X-ray structural analysis. E-1-(exo-8'-Pentacyclo[5.4.0.0²,⁶.0³,¹⁰,0⁵,⁹]undecyl)-2-phenylethylene (16a) was synthesized, and its structure was established via analysis of its 1H, 13C, and 2D COSY NMR spectra. Part III. Reactions of electrophiles, i.e.,:CCl_2, PhSCl, and Br_2, to Z- and E-1,2-di(1'-adamantyl)ethenes (14 and 15, respectively) are described (Scheme 5, 8, 10, and 13 in Chapter 3). Structures of the corresponding products were established unequivocally via analysis of their respective one- and two-dimensional NMR spectra and/or single-crystal X-ray structural analysis. Part IV. An improved asymmetric synthesis of optically active (S)-4-hydroxy-2-cyclohexenone 1 (64%ee, determined via Mosher's method) has been developed (Scheme 5 in Chapter 4). The key step in this synthesis involves the baker's yeast reduction of 13. The absolute configuration of the major product, (S)-1, was established unequivocally via single-crystal X-ray structural analysis of a precursor. The optical purity of the major product 14a (80%de, 67%ee) was established via careful integration of relevant gated-decoupled 13C NMR spectra.

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16

Renard, Annabelle. "Synthèse d'analogues spiraniques de nucléosides et leur incorporation dans des oligonucléotides." Université Joseph Fourier (Grenoble), 1999. http://www.theses.fr/1999GRE10031.

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Notre projet consiste a developper un nouveau type d'oligonucleotides modifies constitue d'un enchainement de spironucleosides, potentiellement capable de reconnaitre des sequences d'adn double brin en formant une triple helice. Nous avons choisi comme premieres unites a incorporer, les desoxyhydantocidines dh# et dh# et les nucleosides spirobarbituriques sb et cb. Ces spironucleosides presentent egalement un interet potentiel en tant que nouveaux analogues de nucleosides biologiquement actifs. Nous avons developpe une voie de synthese efficace des deux epimeres de desoxyhydantocidine dh# et dh#. Nous avons ensuite mis au point deux schemas de synthese stereocontrolee conduisant respectivement aux deux nouveaux spironucleosides sb et cb. La configuration absolue du derive cb a ete confirmee par filiation chimique en aminodiol 106, un intermediaire cle de synthese des nucleosides carbocycliques. Nous avons reussi a obtenir, en utilisant un support solide modifie, des decanucleotides chimeres contenant une, trois ou huit unites spiraniques dh#, dh# ou cb par la methode aux phosphoramidites. Nos resultats preliminaires ont montre une destabilisation des complexes formes entre les decanucleotides contenant ces unites spiraniques et de l'adn simple ou double brin.

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17

Hennequin, Laurent. "Nouvelle méthode de préparation de composés dicarbonylés-1,5 : application à la synthèse de substances naturelles." Rouen, 1986. http://www.theses.fr/1986ROUES026.

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On met au point une méthode générale de synthèse de composés delta-dicarbonylés et delta-dicarbonylés α -halogénés par action respectivement d'un éther d'énol silyle ou d'un éther d'énol silyle β-halogéné sur des carbocations fonctionnels. En milieu basique, les composés delta-dicarbonylés sont transformés en cyclohexénones, tandis que leurs anologues halogénés conduisent, selon la structure du composé de départ, à des cyclopropanes disubstitués trans ou à des spiranes hétérocycliques. Ces méthodes ont été appliquées à la synthèse d'alpha -cypérones. On a également préparé des synthons de bis-annélation et obtenu ainsi la homo-D deshydrotestostérone

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18

Lin, Yu-Hsien, and 林育. "The Synthesis and Chemistry of Tricyclo[3.2.2.02,4]nona-2(4),6-diene." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/21989038887592188264.

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碩士
輔仁大學
化學系
87
Tricyclic 1,2-fused cyclopropene:tricyclo[3.2.2.02,4]nona- 2(4),6-diene 44 is formed by the elimination reaction of2-bromo- 4-chlorotricyclo[3.2.2.02,4]non-6-ene 56 with methyllithium. The products of the Diels-Alder reaction with the compound 44 and 1,3-diphenyl-isobenzofuran (DPIBF) are only endo-addition from the bicyclo[2.2.2]octa-2,5-diene system, and exo- and endo-addition for the cyclopropene system. These products are endo-endo adduct 58 and exo-endo adduct 59. Base on these results, the repulsion of the vinylene group (CH=CH group) and DPIBF higher than that of ethylene group (CH2-CH2 group) and DPIBF. Compound 44 isomerizes to 8-methylenebicyclo[3.2.1]octa- 1,6-diene 65 which is trapped by DPIBF. Compound 58 isomerizes to form compound 60 by irradiation. Both 58 and 59 are stable at refluxing tetrahydrofuran temperature and at UV light. In the presence of trifluoroacetate acid, compound 58 hydrolyzes to form 72, and 59 hydrolyzes in trifluoroacetate acid to form 71 and 72. Both 71 and 72 undergo dehydration and deformylation to give 70. In neat condition, compound 44 will isomerize to vinyl carbene 66 follows by insertion reaction to form 74.

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19

TSOU, YI-JUNG, and 鄒易融. "(I)The Synthesis and Chemistry of 8-Oxatricyclo[3.2.1.02,4]octa-2(4),6-diene(II)Study and Chemistry of exo-2-Bromo-4-Chloro-8-Oxatricyclo[3.2.1.02,4]octa-6-ene and endo-2-Bromo-4-Chloro-Oxatricyclo[3.2.1.02,4]octa-6-ene." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/hjksu6.

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碩士
輔仁大學
化學系
106
(I)The 1,2-bridged polycyclic cyclopropene, 8-Oxatricyclo[3.2.1.02,4]octa-2 (4),6-diene has been synthesized by elimination of exo-2-bromo-4-chloro-8-oxa tricyclo[3.2.1.02,4]octa-6-ene or endo-2-bromo-4-chloro-8-oxatricyclo [3.2.1.02,4]octa-6-ene, cyclopropane 39 was treated with DPIBF to form exo-endo adduct 45﹑exo-exo adduct 46﹑α,β-unsaturated ketone adduct 47 isomerized by exo-endo 45﹑ adduct 48 treated by compound 46 with DPIBF﹑adduct 49 and 50 hydrogenated by adduct 52 and 53﹑unknown adduct 51. (II)exo η2 complex 76 and endo η2 complex 77 has been synthesized by trapping exo-2-bromo-4-chloro-8-oxatricyclo[3.2.1.02,4]octa-6-ene and endo-2-bromo-4-chloro-8-oxatricyclo[3.2.1.02,4]octa-6-ene with iron tetracarbonyl and proved the mechanism of compound 56-59 and 61-65. In addition, there were achieved a new synthestic route to provide tropone derivatives with high yield by use cyclopropenes.

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20

Pon-Won, Chen, and 陳鵬文. "Cycloaddition Reactions of 4-Sulfur-substituted-2-pyridones with Conjugated Dienes." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/71875928223936994613.

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碩士
輔仁大學
化學系
95
This thesis mainly studies the [4+2] cycloaddition reactions of 4-sulfur-substituted 2-pyridones 6, 7, 18, and 20 with several electron-rich dienes, and explores the regio- and stereoselectivity of these reactions. Pyridone 6 reacts as a dienophile with cyclic and acyclic conjugated dienes to give the expected cycloaddition products. Pyridone 7, however, bearing a diene moiety itself, exhibits quite unusual reaction patterns with cyclopentadiene: it reacts as a diene at high temperatures, but reacts both as a dienophile and a diene at 50 oC. The reactivity of sulfoxide 18 is similar to that of sulfone 6, whereas the less-conjugated sulfone 20 is less reactive than compound 6. We have used the PM3 semi-empirical method of HyperChem to calculate the reactivity and regioselectivity of these cycloaddition reactions, and have found that most of the experimental results fit quite well with the theoretical calculations.

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21

Lai, Chun-Chia, and 賴俊嘉. "Density Functional Theory study of [8+2] and [4+2] Cycloaddition Reactions of 2-Oxo-2H-cyclohepta[b]furan derivatives with Dienes." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/80744404394630730734.

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碩士
國立彰化師範大學
化學系
90
Abstract Cycloaddition reactions of 2-Oxo-2H-cyclohepta[b]furan derivates participating as 8π and 4π components respectively toward dienes are described. We use density functional theory (DFT) calculations in the study of transition states and products of title reactions. Possible [4+2] and [8+2] reaction paths were investigated. Our results show that Part 1: [8+2] endo path, is the most likely both thermodynamically and kinetically. The distinct selectivity of the [8+2] endo path over the [4+2] endo one was explained in terms of the secondary orbital interaction (SOI). Part 2: we simulate the substituent effect and compare the result with experiment, the result shows that the more exothermic the reaction, the higer yield the product. Our theoretical prediction is consistent with the experimental observation. Part 3: we apply hetero-atom subsititutions, the result shows that new bicyclo compounds have more aromaticity, leading to increase in the relative energies of intermediates and transition structures. We thus conclude that the cycloaddition reactions with hetero-atom subsititutions are less likely to occur.

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22

顏學仁. "Synthesis and biological activity of naphtho [ 2, 3-d] imidazole-4, 9-dione and its related compounds." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/95205513988626943862.

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23

Lording, William James. "A deeper understanding of the Diels–Alder reaction." Phd thesis, 2010. http://hdl.handle.net/1885/11776.

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The Diels-Alder reaction was discovered in 1928 and has become the most efficient and practical method for the synthesis of six-membered carbocyclic and heterocyclic rings. This thesis comprises three chapters of results and discussion with the Diels-Alder reaction as a theme. Chapter 2 details an investigation of endo:exo selectivity in the Diels-Alder reactions of 1,3-butadiene. Chapter 3 explores aspects of the intramolecular Diels-Alder reactions of some substituted 1,3,8-nonatrienes, and Chapter 4 describes the domino Diels-Alder reactions of 1,4-diiodo-1,3-butadiene. The Diels-Alder reaction is powerful, general, and widely used in chemical synthesis, and it is well known that many Diels-Alder reactions exhibit endo selectivity, in accord with Alder’s empirical rule. The origins of endo:exo selectivity in the Diels-Alder reaction, however, are not completely understood and there is a dearth of experimental evidence concerning the Diels-Alder reactions of the archetypal 1,3-diene, 1,3- butadiene. Chapter 2 describes a study of the Diels-Alder reactions of an isotopically labelled 1,3-butadiene with a range of simple dienophiles, allowing the endo:exo selectivities of these important reactions to be determined for the first time. The experimental data shed light on the origins of endo:exo selectivity in the Diels-Alder reaction and will serve as an important reference for future computational investigations in this area. The intramolecular Diels-Alder reaction shares many of the virtues of its intermolecular counterpart, however its use in chemical synthesis is limited because intramolecular Diels-Alder reactivity and stereoselectivity are often governed by subtle factors, and can be very difficult to predict. As part of a comprehensive experimental and computational collaboration, Chapter 3 describes an investigation of the heat and Lewis acid promoted intramolecular Diels-Alder reactions of some ether tethered 1,3,8-nonatrienes. Also presented are the results of a rate study and a kinetic isotope effect study involving the intramolecular Diels-Alder reactions of some 1,3,8-nonatrienes. The experimental data are analysed and compared with predicted stereoselectivities, activation barriers and kinetic isotope effects obtained from computational modelling. Increased efficiency in chemical synthesis conserves resources, reduces waste, and saves time and money. Domino reactions are particularly efficient processes, which can generate complex products from simple reactants. Chapter 4 describes an investigation of the domino Diels-Alder reactions of (1E,3E)-1,4-diiodo-1,3-butadiene with maleimide dienophiles, through which a family of bicyclo[2.2.2]oct-2-ene derivatives are produced in one high yielding and stereoselective synthetic step.

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24

Abid, Obaid-ur-Rahman [Verfasser]. "Synthesis of functionalized 4-chlorophthalates, 2-naphthoates, 2-fluorobiaryls, and arylpyridines by cyclocondensation reactions of 1,3-bis(silyloxy)-1,3-butadienes and related dienes and by palladium(0) catalyzed cross coupling reactions / vorgelegt von Obaid-ur-Rahman Abid." 2010. http://d-nb.info/100780808X/34.

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25

Huang, Chin-Neng, and 黃志能. "Part I、Design and synthesis of 3-(2-Phenyl-4H-thio-chromen-4-yildene)-3H-chromene-2,4-dione derivatives as potential redox switchesPart II、Design and Synthesis of 7-N,N-dimethylamino-4-hydroxycoumarin-based derivatives as potential organic photochromi." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/33645529616308159980.

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碩士
東海大學
化學系
95
Part I、Design and synthesis of 2'-phenyl-[3,4']bichromenylidene -2,4-dione derivatives as potential redox switching Tow 3-(2-Phenyl-4H-thiochromen-4-yildene)-3H-chromene-2,4-dione derivatives were synthesized in several steps from thiophenol and 4-hydroxycoumarins with overall yields of 65 and 67%. The prepared compounds 16 and 21 instantly changed from either purple or bule to colorless when treated them with sodium borohydride in methanol. The resulting reduced compounds reverted to their original colors after the reducing agent was removed. While no fluorescence of N,N-dimethylamino substituted compound 21 was detected prior to reduction, the reduced compound 22 emitted fluorescence with the quantum yield of 0.19 in methanol. Part I: Design and Synthesis of 7-N,N-dimethylamino- 4-hydroxycoumarin-based derivatives as potential organic photochromic colorants and redox switches A series of 2H-pyrano[3,2-c]chromen-5-one derivatives were synthesized. Their photochromic properties were investigated by the UV-vis absorption spectroscopy, and were compared to that of chromenes. Compounds 11 and 13a-b mainly existed in the ring-opened forms when one or two phenyl groups were incorporated on the 2-position. Incorporation of a methyl substituent on 3-position completely abolished their photochromic behavior. Compounds 5b with an N,N-dimethylamino group on the aromatic ring displayed an increasing shoulder absorption in the visible region and a distinct change of color upon UV irradiation.

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26

Kappelmayer, Diane [Verfasser]. "Die Expression der EGF-Rezeptor-Familie (HER-1, HER-2, HER-3, HER-4) im extravillösen Trophoblasten im Vergleich zwischen normalen humanen Plazenten und Plazenten von Frauen mit hypertensiven Schwangerschaftserkrankungen / vorgelegt von: Diane Kappelmayer." 2007. http://d-nb.info/988408465/34.

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27

Beerlink, Johannes. "Totalsynthese der Mansouramycine A-E aus Streptomyces sp. und Rhodium-katalysierte 1,2-Additionen an cyclische Enone." Doctoral thesis, 2008. http://hdl.handle.net/11858/00-1735-0000-0006-AD4C-2.

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Дисертації з теми "4+2 diene"

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