Les travaux de cette thèse ont porté sur le développement de nouvelles méthodes de synthèse autour de la chimie des réactions multicomposants et des réactions de Tsuji-Trost des dérivés nitrés et phosphorylés. Dans le chapitre I, nous avons développé une nouvelle voie d’accès aux indoles propargyliques impliquant des adduits A3 et une réaction d’élimination d’amine en présence du 1,2-dibromoethane. Dans le chapitre II, nous avons démontré la possibilité d’exploiter des réactions de Tsuji-Trost par la formation de produits O-allylés issus des α-hydroxyphosphonates. La méthatèse cyclisante appliquée sur une gamme d’α-hydroxyphosphonates O-allylés a permis de synthétiser des phosphono-oxahétérocycles. Par ailleurs nous avons aussi démontré l’intérêt des α-hydroxyphosphonates du cinnamaldehyde pour des tandems Tsuji-Trost/ Claisen par la formation de dérivés d’acides α allylés. Dans le chapitre III, nous avons décrit un couplage entre les acides boroniques et les nitronates silylés pour aboutir à des oximes α, β insaturés. Par la suite nous avons convertis les oximes α,β-insaturés obtenus en isoxazoles par une cyclisation oxydante . Finalement dans le chapitre IV, nous avons poursuivi sur les réactions de Tsuji-Trost en mettant au point une synthèse de diènes à partir de dérivés nitrés allyliques. Cette réaction a été élargie à la synthèse des naphatlènes substitués en position 1. / The work of this thesis focused on the development of new synthesis methods around the chemistry of multicomponent reactions and Tsuji-Trost reactions of nitro and phosphorylated derivatives. In Chapter I, we developed a new pathway to propargylic indoles involving A3 adducts and an amine removal reaction in the presence of 1,2-dibromoethane. In Chapter II, we demonstrated the possibility of exploiting Tsuji-Trost reactions by the formation of O-allyl products from α-hydroxyphosphonates. The ring closing metathesis applied to a range of O-allylated α-hydroxyphosphonates allowed phosphono-oxaheterocycles to be synthesized. Furthermore, we also demonstrated the interest of α-hydroxyphosphonates from cinnamaldehyde for Tsuji-Trost / Claisen tandems by the formation of α-allylated acid derivatives. In Chapter III, we described a coupling between boronic acids and silylated nitronates to produce α, β-unsaturated oximes. Subsequently we converted the α, β-unsaturated oximes obtained in isoxazoles by an oxidizing cyclization. Finally, in Chapter IV, we continued the reactions of Tsuji-trost by developing a synthesis of dienes from allylic nitro derivatives. This reaction has been extended to the synthesis of naphatlene substituted at the 1-position.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第19476号 / 理博第4136号 / 新制||理||1595(附属図書館) / 32512 / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 川上 則雄, 教授 石田 憲二, 教授 高橋 義朗 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

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Disordered multicomponent nitride thin film can be used for various applications. The focus of this Licentiate Thesis lies on the theoretical study of piezoelectric properties, phase stability and surface diffusion in multifunctional hard coating nitrides using density functional theory (DFT). Piezoelectric thin films show great promise for microelectromechanical systems (MEMS), such as surface acoustic wave resonators or energy harvesters. One of the main benefits of nitride based piezoelectric devices is the much higher thermal stability compared to the commonly used lead zirconate titanate (PZT) based materials. This makes the nitride based material more suitable for application in, e.g., jet engines. The discovery that alloying AlN with ScN can increase the piezoelectric response more than 500% due to a phase competition between the wurtzite phase in AlN and the hexagonal phase in ScN, provides a fundamental basis for constructing highly responsive piezoelectric thin films. This approach was utilized on the neighboring nitride binaries, where ScN or YN was alloyed with AlN, GaN, or InN. It established the general role of volume matching the binaries to easily achieve a structural instability in order to obtain a maximum increase of the piezoelectric response. For Sc0.5Ga0.5N this increase is more than 900%, compared to GaN. Y1-xInxN is, however, the most promising alloy with the highest resulting piezoelectric response seconded only by Sc0.5Al0.5N. Phase stability and lattice parameters (stress-strain states) of the Y1-xAlxN alloy have been calculated in combination with experimental synthesis. Hard protective coatings based on nitride thin films have been used in industrial applications for a long time. Two of the most successful coatings are TiN and the metastable Ti1-xAlxN. Although these two materials have been extensively investigated both experimentally and theoretically, at the atomic level little is known about Ti1-xAlxN diffusion properties. This is in large part due to problems with configurational disorder in the alloy, because Ti and Al atoms are placed randomly at cation positions in the lattice, considerably increasing the complexity of the problem. To deal with this issues, we have used special quasi-random structure (SQS) models, as well as studying dilute concentrations of Al. One of the most important mechanisms related to the growth of Ti1-xAlxN is surface diffusion. Because Ti1-xAlxN is a metastable material it has to be grown as a thin film with methods such as physical vapor deposition (PVD), in which surface diffusion plays a pivotal role in determining the microstructure evolution of the film. In this work, the surface energetics and mobility of Ti and Al adatoms on a disordered Ti0.5Al0.5N(001) surface are studied. Also the effects on the adatom energetics of Ti, Al, and N by the substitution of one Ti with an Al surface atom in TiN(001), TiN(011), and TiN(111) surfaces is studied. This provides an indepth atomistic understanding of how the energetics behind surface diffusion changes as TiN transitions into Ti0.5Al0.5N. The investigations revealed many interesting results. i) That Ti adatom mobilities are dramatically reduced on the TiN and Ti0.5Al0.5N(001) surfaces while Al adatoms are largely unaffected. ii) The reverse effect is found on the TiN(111) surface, Al adatom migration is reduced while Ti adatom migration is unaffected. iii) The magnetic spin polarization of Ti adatoms is shown to have an important effect on binding energies and diffusion path, e.g., the adsorption energy at bulk sites is increased by 0.14 eV.

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Interdiffusion in multicomponent-multiphase alloys is commonly encountered in many materials systems. The developments of multicomponent-multiphase alloys require control of microstructure through appropriate heat treatment, involving solid-state transformations, precipitation processes, and surface modification, where the interdiffusion processes play a major role. In addition, interdiffusion processes often control degradation and failure of these materials systems. Enhanced performance and reliable durability always requires a detailed understanding of interdiffusion. In this study, ternary and quaternary interdiffusion in Ni-Cr-X (X = Al, Si, Ge, Pd) at 900°C and 700°C, Fe-Ni-Cr-X (X = Si, Ge) at 900°C, and Ni3Al alloyed with Ir, Ta and Re at 1200°C were examined using solid-to-solid diffusion couples. Interdiffusion fluxes of individual components were calculated directly from experimental concentration profiles determined by electron probe microanalysis. Moments of interdiffusion fluxes were examined to calculate main and cross interdiffusion coefficients averaged over selected composition ranges from single diffusion couple experiments. Consistency in the magnitude and sign of ternary and quaternary interdiffusion coefficient were verified with interdiffusion coefficients determined by Boltzmann-Matano analysis that requires multiple diffusion couples with intersecting compositions. Effects of alloying additions, Al, Si, Ge and Pd, on the interdiffusion in Ni-Cr-X and Fe-Ni-Cr-X alloys were examined with respect to Cr2O3-forming ability at high temperature. Effects of Ir, Ta and Re additions on interdiffusion in Ni3Al were examined with respect to phase stability and site-preference. In addition, a numerically refined approach to determine average ternary interdiffusion coefficients were developed. Concentrations and moments of interdiffusion fluxes are employed to generate multiple combinations of multicomponent interdiffusion coefficient as a function of moments. The matrix of multicomponent interdiffusion coefficients corresponds to the lowest order of the moment. It yields real and positive eigen values which provides reliable average interdiffusion coefficients for the selected composition range.

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