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京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21275号 / 工博第4503号 / 新制||工||1700(附属図書館) / 京都大学大学院工学研究科合成・生物化学専攻 / (主査)教授 杉野目 道紀, 教授 村上 正浩, 教授 松原 誠二郎 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

The possibility of inducing intramolecular SRN! reactions in two 2-(o-halobenzyl)- amides, 2-(o-iodobenzyl)-N,N,N’N’-tetramethylsuccinamide (77) and 2-(o-iodobenzyl)- N,N,N’N’-tetramethylglutaramide (80), and three 3-(o-halobenzyl)imides, 3-(oiodobenzyl)succinimide (99), 3-(α-cyano-o-bromobenzyl)succinimide (82) and 3-(oiodobenzyl)glutarimide (108), was investigated. All of these substrates were prepared during the course of the investigation. Treatment of 77 and 80 with excess potassium amide in liquid ammonia under photostimulated conditions afforded reasonably good yields of the expected cyclized products, 1,2-bis-(N,N-dimethylcarboxamido)indane (78) and 1,3-bis-(N,N-dimethylcarboxamido)-1,2,3,4-tetrahydronaphthalene (81), respectively. When imide 99 was subjected to similar conditions, it also underwent the expected cyclization, affording succinimido[3,4-b]indane (61) in acceptable yield. Mechanistic investigations revealed that all of the above reactions appear to occur via intramolecular S_RN1 processes. Attempts to induce similar cyclization reactions with 3-(α-cyano-o-bromobenzyl)- succinimide (82) and 3-(o-iodobenzyl)glutarimide (108) proved unsatisfactory. Substrate 82 failed to undergo cyclization to give the desired succinimido[3,4-b]indane-8-carbonitrile (83). Instead, 3-(α-cyano-α-phenylmethyleno)succinimide (107) was formed as the sole isolable product, presumably via an intramolecular β-hydrogen atom abstraction process. 3-(o-Iodobenzyl)glutarimide (108) did not undergo the desired cyclization to give 1,2,3,4,5,6-hexahydro- 1,5-methano-3-benzazocine-2,4-dione (62) either, presumably because of steric hindrance. This study was undertaken with the objective of investigating the possibility of inducing intramolecular S_RN1 reactions in appropriately substituted amide and imide derivatives. The specific substrates, 77, 80, 82, 99 and 108, were selected for the study because it appeared that intramolecular S_RN1 reactions with these substrates would result in the formation of products that might be useful in the development of new anticonvulsant agents. In this context, the preparation of succinimido[3,4-b]indane (61), which seemed likely to possess antiepileptic properties, fulfilled our proposed objective of applying novel chemistry to the preparation of a new potential anticonvulsant agent. The successful cyclization of 77 and 80 into the expected products, 1,2-bis-(N,Ndimethylcarboxamido)indane (78) and 1,3-bis-(N,N-dimethylcarboxamido)-1,2,3,4- tetrahydronaphthalene (81), respectively, also represented the application of novel chemistry to the formation of two other benzo-fused systems. The synthetic and mechanistic investigations undertaken during this study are expected to extend the scope of the synthetic utility of intramolecular S_RN1 chemistry. / Ph. D.

The chemistry of the radical anion generated from 1,I-dimethyl-5,7-di-tbutylspiro[ 2,5]octa-4,7-dien-6-one (<b>20</b>) was studied electrochemically using cyclic and linear sweep voltammetry (CV, LSV). The reduction potential of <b>20</b> was estimated to be -2.5 V VS. 0.1 M Ag⁺/Ag, similar to the reduction potentials observed for aryl ketones and enones. LSV results for the reduction of <b>20</b> are consistent with the occurrence of substrate reduction followed by a subsequent chemical step (an EC mechanism). The broadness of the reduction wave and variation of peak potential with sweep rate suggest that the rate limiting step is heterogeneous electron transfer. Ring opening of the radical anion generated from <b>20</b> results in a 9:1 ratio of the 3° and 1° distonic radical anions. The rate constant for ring opening has been estimated to be k ≥ 10⁷s⁻¹ with a calculated (AM1) enthalpy of ring opening of ΔH° > -15 kcal/mol. The facile nature of radical anion ring opening can be ascribed to the relief of cyclopropyl ring strain in conjunction with the establishment of aromaticity. On this basis, the regiochemistry of the ring opening of the radical anion derived from <b>20</b> suggests that polar and SET pathways can be differentiated based upon the regiospecificity of cyclopropyl ring opening. In reactions between <b>20</b> and nucleophiles known to react via SET with carbonyl compounds, 20 successfully produced products characteristic of SET pathways. However, subsequent studies of the reaction between <b>20</b> and thiophenoxide, a nucleophile purported to undergo SET, produced no evidence for a SET pathway. It was discovered that ring opened products may also be formed by competing polar pathways involving a carbocationic intermediate, especially in protic solvents. In dipolar aprotic solvents, ring opening occurs primarily via an S_N2 process, with nucleophilic attack occurring preferentially at the least hindered carbon. The strengths and weaknesses of <b>20</b> as a SET probe are discussed / Ph. D.

In the Introduction part of this thesis, the chemistry of organofluorine compounds is discussed, particularly the methods for the preparation of organofluorine compounds mainly by fluoroalkylation methods. Furthermore, the chemistry of fluorinated phosphonates, methods of their preparation, reactivity and biological activity is discussed. Additionally, the reactivity of fluoromethane derivatives is briefly mentioned and especially, the reactivity of diethyl fluoromalonate and fluorobisfenylsulfonylmethane is described. The Results and discussion part is devoted to the reactivity of three fluorinated phosphonates: tetraethyl fluoromethylenbisphosphonate, diethyl fluorophenylsulfonylphosphonate and previously not described diethyl fluoronitromethylphosphonate. These fluorinated phosphonates belong to the family of nucleophilic monofluoroalkylation reagents, meaning that these compounds are convenient starting materials for the synthesis of complex organic molecules containing the fluorine atom. The results deal with the reactivity of above mentioned fluorinated phosphonates, mainly with alkylation reactions, Horner-Wadsworth-Emmons reactions and conjugated additions. Also, other synthetic methods such as the Mitsunobu reaction or the palladium catalyzed allylation reaction were investigated; however,...

Efetuaram-se as reações de nucleófilos de oxigênio (MeONa, EtONa, PhONa e t-BuOK) com o aduto de Diels-Alder cloranil-ciclopentadieno, com o objetivo de se obterem os correspondentes adutos poli-substituídos. Nas reações com MeONa e EtONa foram empregadas tanto quantidades estequiométricas como excesso destes alcóxidos. Nestes últimos casos, foram obtidos dois produtos. Um destes, quando se empregou MeONa, apresentou a mesma estrutura que o aduto cis,endo-2,5-dicloro- 3,6-dimetóxi-p-benzoquinona-ciclopentadieno. O outro produto (B), isolado na forma de óleo, apresentou dados de RMN e de composição que indicaram tratar-se do aduto trans-2,5-dicloro-3,6-dimetóxi-p-benzoquinona-ciclopentadieno ou trans-2,6- dicloro-3,5-dimetóxi-p-benzoquinona-ciclopentadieno, com os grupos OMe e Cl em posições endo e exo, respectivamente. Experiências conduzidas com EtONa levaram a produtos semelhantes. As tentativas de substituir o átomo de cloro ligado ao sistema enodiônico de B foram bem sucedidas quando se empregaram PhSNa ou MeSNa, mas falharam quando se usou o PhSO2Na. Estes produtos de substituição, B-SPh e B-SMe, foram isolados como sólidos amorfos, o que não permitiu que tivessem as suas estruturas determinadas por difração de raios-X. Outros experimentos com o aduto de Diels-Alder cloranil-ciclopentadieno envolveram o uso de PhONa, PhSO2Na e dimetilamina como nucleófilos. Enquanto no caso de PhONa e dimetilamina obtiveram-se os adutos mono-substituídos correspondentes, no caso de PhSO2Na, em metanol, obteve-se a substituição dos dois átomos de cloro do aduto de Diels-Alder cloranil-ciclopentadieno pelos grupos OMe e PhSO2. / The reactions between the chloranil-cyclopentadiene Diels-Alder adduct and alkoxides (MeONa, EtONa, PhONa e t-BuOK) were carried out aiming the synthesis of the corresponding poly-substituted adducts. In the case of reactions with MeONa and EtONa, equimolar and excess of such nucleophiles were employed. When MeONa was in excess, two products were obtained. One of them was proved to be the cis,endo-2,5-dichloro-3,6-dimethoxy-p-benzoquinone-cyclopentadiene adduct. The other product (B), isolated as an oil, exhibited elemental composition and NMR data that indicate its structural identity with the trans-2,5-dichloro-3,6-dimethoxy-p-benzoquinone-cyclopentadiene or the trans-2,6-dichloro-3,5-dimethoxy-p- benzoquinone-cyclopentadiene adduct, lying the OMe and Cl groups in an endo and exo positions, respectively. The experiments conducted with EtONa lead to the similar products. Aiming the substitution of the chlorine atom that remains attached to the enedionic system of B, this latter compound was successfully reacted with PhSNa and MeSNa, but was unable to react with PhSO2Na.. The corresponding B-SPh and and B-SMe derivatives were isolated as amorphous solids thus precluding their use for their structural determination by X-ray crystallography. Other reactions with chloranil-cyclopentadiene Diels-Alder adduct included the use of PhONa, PhSO2Na and dimethylamine as nucleophiles. In the case of PhONa and However, the reaction of chloranil-cyclopentadiene Diels-Alder adduct and PhSO2Na, in methanol, lead to the substitution of both enodionic chlorine atoms by the OMe and PhSO2 groups.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-04-24T14:13:26Z No. of bitstreams: 1 2012 - Ana Carolina Bello de Souza.pdf: 1911170 bytes, checksum: 62c70571aeb2100b8313dc1ef44eac2b (MD5) / Made available in DSpace on 2017-04-24T14:13:26Z (GMT). No. of bitstreams: 1 2012 - Ana Carolina Bello de Souza.pdf: 1911170 bytes, checksum: 62c70571aeb2100b8313dc1ef44eac2b (MD5) Previous issue date: 2012-10-03 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / In this work, the theoretical study of the gas-phase bimolecular nucleophilic substitution reaction, CH3Cl + OH- CH3OH + Cl-, is introduced, aiming the description of the potential energy surface, the calculation of rate constants and the investigation of the effect of increasing the side chain (changing the CH3 radical in the reaction cited above by the radicals ethyl, n-propyl, i-propyl, n-butyl, s-butyl e t-butyl). The theoretical calculations have been first performed at the MP2/6-31+G(d) level for the geometry optimizations and vibrational frequencies calculations. Single point calculations at the CCSD(T)/6-31+G(d) level have also been performed in order to improve the total energies for the stationary points. However, the relative energies of these stationary points at both MP2 and CCSD(T) level shown close results, so that the single point calculations at the CCSD(T) level have not been proved strictly necessary and have therefore not been performed for all the points along the potential energy surface. The minimum energy path has been described by the intrinsic reaction coordinate method, calculated at the MP2/6-31+G(d) by performing sequential geometry optimizations starting from the saddle point. The calculated enthalpy difference at 298K for the reaction has been determined as -49.5 kcal/mol, in good agreement with the literature value: -50.5 kcal/mol. The calculated rate constant has been obtained as 1.41 x 10-9 cm3.molecule-1.s-1, at 298,15K, in excellent agreement with the experimental data: 1.3 ? 1.6 x 10-9 cm3.molecule-1.s-1.Moreover, the rate constants show non-Arrhenius behavior, decreasing as the temperature increases, which is consistent with the experimental expectation. In this way, the performance of the variational transition state theory for this reaction can be considered satisfactory. By increasing the side chain of the reactant, other reaction channels have been observed: the bimolecular elimination E2 channel and the attack of the nucleophile from the same plane of the exit group (the front-SN2).For these reactions of the alkyl chlorides on n carbon atoms (1 < n ? 4), the B3LYP/6-31+G(d,p) level has been adopted for geometry optimizations and vibrational frequencies. Then, single point calculations at the CCSD(T)/6-31+G(d,p)//B3LYP/6- 31+G(d,p) level have been performed. A comparison of the reaction channels, back- SN2 and E2, shows that the E2 channel is kinetically favored, whereas the SN2 products are thermodynamically more stable. As expected, high values for the potential height have been observed for the front-SN2, being these channels disfavored in all cases. In general, the energy of the saddle points in respect to the isolated reactants slightly depend upon the size of the side chain. / Este trabalho trata do estudo te?rico das rea??es de substitui??o nucleof?lica de segunda ordem, CH3Cl + OH- CH3OH + Cl-, em fase gasosa, visando estudar a superf?cie de energia potencial, obter as constantes de velocidade e ainda verificando o efeito do aumento da cadeia lateral (trocando o radical CH3 na rea??o descrita acima por radicais etil, n-propil, i-propil, n-butil, s-butil e t-butil). Primeiramente, c?lculos te?ricos para otimiza??es de geometria e frequ?ncia foram realizados em n?vel MP2/6-31+G(d) para a rea??o CH3Cl + OH- CH3OH + Cl- e, em seguida, c?lculos single-point em n?vel CCSD(T)/6-31+G(d) foram realizados para corrigir os valores da energia eletr?nica dos pontos estacion?rios obtidos no caminho de rea??o. Entretanto, os valores obtidos para as energias relativas em n?veis MP2 e CCSD(T) foram muito pr?ximos, n?o sendo estritamente necess?rio refinar,atrav?s de c?lculos single-point em n?vel CCSD(T)/6- 31+G(d),os valores de energia de todos os pontos obtidos na superf?cie de energia potencial. O caminho de rea??o menor energia foi descrito pela coordenada de rea??o intr?nseca, calculada por otimiza??es de geometrias de uma sequ?ncia de configura??es ao redor do ponto de sela em n?vel MP2/6-31+G(d). A diferen?a de entalpia a 298K calculada para a rea??o foi de -49,5 kcal/mol, em bom acordo com o dado da literatura, -50,5 kcal/mol. A constante de velocidade da rea??o obtida foi de 1,41 x 10-9 cm3.mol?cula-1.s-1, a 298,15K, em excelente acordo com o dado experimental: 1,3 ? 1,6 x 10-9 cm3.mol?cula-1.s-1. Al?m disso, as constantes de velocidade globais apresentam comportamento n?o-Arrhenius, diminuindo conforme a temperatura aumenta, em um perfil consistente com a observa??o experimental. Dessa forma, a aplica??o da teoria de estado de transi??o se mostra satisfat?ria para essa rea??o. A partir do aumento da cadeia lateral, outros canais de rea??o foram observados, em prov?vel competi??o ? substitui??o nucleof?lica de ordem 2: a elimina??o de segunda ordem, E2. O ataque do nucle?filo pela frente da cadeia tamb?m foi obtido e investigado. Para as rea??es dos cloretos de alquila com cadeia lateral de n carbonos (1 < n ? 4), o n?vel B3LYP/6- 31+G(d,p) foi adotado para c?lculos de otimiza??es e frequ?ncias. Posteriormente, c?lculos em n?vel CCSD(T)/6-31+G(d,p)//B3LYP/6-31+G(d,p) foram realizados. Comparando os canais de rea??o de substitui??o nucleof?lica back e de elimina??o, o canal cineticamente favorecido foi o de elimina??o, por?m os produtos termodinamicamente mais est?veis s?o os de substitui??o nucleof?lica. Como esperado, observa-se uma barreira de potencial muito alta para as rea??es substitui??o pela frente, sendo esses canais desfavorecidos em todos os casos.Em geral, a diferen?a de energia dos pontos de sela em rela??o aos reagentes isolados mostra pequena depend?ncia com o aumento da cadeia lateral linear

Different monomeric diols, with a central rigid FD unit connected with two aliphatic chains of various length, were prepared to react with aromatic mesogenic triad, TOBC. In this manner, thermotropic polyesters with possible low thermal transition temperatures (including Tmand Ti) and high solubility in organic solvent can be generated in view of the non-linear polymeric chain imposed by the rigid, bent FD moieties. In addition to the effect of the aliphatic chain length, polyesters of different molecular weight will be obtained by different synthesis approach (or fractionation of the resulting polyester product) and therefore, the influence of molecular weight on liquid crystalline properties can be evaluated.

Thesis (Ph. D.)--University of Washington, 2003. / Vita. Includes bibliographical references (leaves 164-177).