Kwoli Chui. / "August 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (p. 122-140). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Bibliography: leaves 177-193 / v, 193 leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Organic Chemistry, 1985

Thesis (Ph. D.)--University of Adelaide, Dept. of Organic Chemistry, 1985. / Includes bibliographical references (leaves 177-193).

Thesis(M.S.)--Auburn University, 2005. / Abstract. Includes bibliographic references (leaves 61-68).

Rhodium-catalysed enantioselective allylation reaction of imines in the presence of chiral diene ligands has been investigated. Under the optimised conditions, cyclic imines provided homoallylic amines in high yield and excellent enantioselectivities. The reaction most likely proceeds via allylrhodium(I) intermediates, and represents the first rhodium-catalysed enantioselective nucleophilic allylation of π-electrophiles with allylboron compounds. Furthermore, the allylations display a strong preference for carbon–carbon bond formation at the more substituted terminus of the allyl fragment of the allyltrifluoroborate. To demonstrate the utility of the allylation products, representative manipulations were conducted. Enantioselective Nickel-Catalysed Michael Additions of 2-Acetylazaarenes to Nitroalkenes An enantioselective Michael addition of acylazaarenes with α-substituted β-nitroacrylates in the presence of a chiral Ni(II)–bis(oxazoline) complexes has been developed. A range of azaaryl nucleophiles were shown to react with a variety of nitroalkenes to construct highly functionalised Michael addition products which contain a stereogenic all-carbon quaternary stereocentre with moderate to high yields and enantioselectivities. A possible mechanism for this reaction has been proposed.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20411号 / 工博第4348号 / 新制||工||1674(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 中尾 佳亮 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

Thesis advisor: Marc M. Snapper / Thesis advisor: James J. Morken / This dissertation will present three main projects focusing on the catalytic enantioselective synthesis and stereospecific functionalization of tertiary alkylboronates. In the first project, acyl chlorides were incorporated as a new class of electrophile in conjunctive cross-coupling, from which, a variety of tertiary β-boryl amides were successfully synthesized with high enantioselectivity. The utility of the tertiary alkylboronates products was also demonstrated through several orthogonal functionalizations of the boronic ester group and amide groups. The project culminated in the enantioselective total synthesis of natural product (+)-adalinine that leveraged this newly developed methodology. In the second project, a conjunctive cross-coupling enabled ring closure was developed to synthesize tertiary alkylboronates residing on carbocyclic and heterocyclic scaffolds. A Phosphinooxazoline (Phox) ligand was identified as a non-expensive ligand that catalyzed the conjunctive cyclization reaction with high enantioselectivity. A Series of synthetically challenging enantimerically enriched spirocyclic and aryl bicyclic tertiary alkylboronates were efficiently generated using this method, and several cyclopentyl boronic esters with two continuous stereogenic centers were synthesized with high diastereoselectivity. In the third project, a Rh-catalyzed diboration reaction was successfully employed to diborate monosubstituted cyclobutenes with excellent enantioselectivity. The less sterically hindered secondary boronic ester units in the diboron products can be regioselectively functionalized using the newly developed tert-butyllithium activation-transmetallation strategy. As a result, a variety of stereochemically defined β-substituted cyclobutyl tertiary boronic esters were synthesized with high efficiency. / Thesis (PhD) — Boston College, 2024. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Chemistry.

The synthesis, photophysical and electronic properties of a series of novel boron containing fused and ladder type donor-acceptor (D-A) oligomers and polymers are reported. The synthesis was achieved through coordination of the basic functionality of the ubiquitous benzothiadiazole acceptor unit onto a boron Lewis acid followed by an electrophilic aromatic borylation resulting in the formation of fused and ladder type structures (termed borylative fusion). The novel C,N-chelated borane structures disclosed herein are a new member of a large family of tetra-coordinate organoboron compounds that are used for the construction of highly emissive materials. Upon borylation large bathochromic shifts in the absorption and fluorescence spectra were observed, DFT and cyclic voltammetry demonstrate that this is a result of a significant reduction of the LUMO energy levels whist the HOMO energy levels remains relatively unperturbed. These large bathochromic shifts lead to materials that show far red/NIR emission in the solid state with absolute quantum yields of up to 44%. Furthermore, the frontier molecular orbital energy levels of these fused structures can be modulated through judicious selection of the exocyclic boron substituents. These novel borocycles also proved stable to a range of cross-coupling conditions which facilitated further modulation of the frontier molecular orbitals and emissive properties. Borylative fusion was also applicable to D-A conjugated polymers, this represents a facile post-polymerisation functionalisation that is an effective method of modulating the photophysical properties of D-A conjugated polymers. Solution processed OLEDs with far red/NIR electroluminescence (EL) were fabricated from these materials. These devices showed good external quantum efficiency values (EQE) for the far red/NIR region of the electromagnetic spectrum (EQE > 0.4 % for maximum EL > 700 nm).

Ces travaux de thèse portent sur l’élaboration et l’étude des propriétés thermomécaniques de polymères dynamiques incorporant des dérivés borés. Tout en appliquant ce concept sur une variété d’architectures macromoléculaires : copolymères fonctionnels, briques di- et tri-fonctionelles, deux réactivités distinctes du bore ont été étudiées et exploitées. Une large gamme de méthodes de caractérisation a été utilisée pour mener à bien ce projet : spectroscopies FTIR et RMN sous différents stimuli, ainsi que de nombreuses analyses thermiques et mécaniques. Dans un premier temps, nous avons considéré la formation de paires de Lewis frustrées entre des acides de Lewis (organoboranes) et des bases de Lewis (amines et phosphines) stériquement encombrés, cette interaction pouvant être fortement modulée par la participation d’un troisième composé tels que des molécules de gaz. Ainsi, nous avons été capables de former des réseaux dynamiques réticulables de façon réversible avec le dioxyde de carbone. Dans un second temps, nous avons mis en évidence une nouvelle réactivité dans les esters boroniques cycliques impliquant une ouverture de cycle à haute température, assistée par la présence de nucléophiles. Cette réaction a été mise à profit pour former des polymères réticulés dynamiquement, pouvant atteindre des températures de transition vitreuse jusqu’à 220°C et dé-réticulables par dilution avec un bon solvant du polymère (apolaire). Cette réactivité a été appliquée à une variété de polymères accessibles par copolymérisation radicalaire (styrène, éthylène, acétate de vinyle, acrylate de butyle) ou par post-fonctionnalisation de polymères commerciaux (polybutadiène) / This thesis focuses on the development and study of thermomechanical properties of dynamic polymers incorporating borylated derivatives. While applying this concept to a variety of macromolecular architectures: functional copolymers, di- and tri-functional bricks, two distinct reactivities of boron have been explored. A wide range of characterization methods has been used to carry out this project: FTIR and NMR spectroscopies under numerous stimuli, as well as many thermal and mechanical analyses. In a first step, we considered the formation of Frustrated Lewis Pairs between Lewis acids (organoboranes) and Lewis bases (amines and phosphines) sterically hindered, as this interaction can be strongly modulated by the participation of a third compound such as gas molecules. Thus, we have been able to form dynamic networks reversibly crosslinkable with carbon dioxide. In a second step, we demonstrated a new reactivity in cyclic boronic esters involving a ring-opening at high temperature, assisted by the presence of nucleophiles. This reaction has been used to form dynamically crosslinked polymers, which can reach glass transition temperatures up to 220°C and de-crosslinkable by dilution in a good (apolar) polymer solvent. This reactivity has been applied to a variety of polymers accessible by radical copolymerization (styrene, ethylene, vinyl acetate, butyl acrylate) or by post-functionalization of commercial polymers (polybutadiene)

A utilização de sondas fluorescentes para marcação ou detecção de biomoléculas de interesse em processos biológicos distintos, vem recebendo grande atenção em pesquisas biomédicas, de análises clínicas e biologia celular. Em geral, estas sondas fluorescentes são constituídas por moléculas orgânicas pequenas, as quais apresentam características fluorescentes e capacidade de conjugar-se com estas biomoléculas. Desta forma, esta dissertação descreve inicialmente a síntese de compostos 2-aril ou 2,5- diarilfuranos e tiofenos (3, 5, 7 e 9a-i), a partir de espécies orgânicas de telúrio (1, 4, 6 e 8) e sais de ariltrifluoroboratos de potássio (2a-i), via reação de acoplamento cruzado tipo Suzuki-Miyaura, sob catálise de paládio [ver a figura no arquivo original]. Em seguida, descreve a síntese de um derivado 2,5-diarilfurano assimétrico, o 2-(3-aminofenil)-5-(4-metoxifenil)furano 11, o qual apresenta propriedades químicas e luminescentes adequadas para atuar como uma nova e promissora sonda fluorescente em processos de marcação ou detecção biológica. A síntese desta nova sonda, também chamada de 3-AFA (3-AnililFuranoAnisol), foi realizada a partir da reação de acoplamento cruzado tipo Suzuki-Miyaura, sob catálise de paládio, entre o ácido (3-aminofenil) borônico 5e e o 2- (butiltelanil)-5-(4-metoxifenil)furano 10 em 65 % de rendimento. Esta nova sonda 3-AFA 11 foi conjugada com uma série de L-aminoácidos 12a-l, a partir de uma reação de acoplamento peptídico para formação dos respectivos produtos 13a-l em rendimentos satisfatórios. Estes produtos conjugados 13a-l, apresentam potencial para marcação fluorescente de enzimas proteolíticas de interesse [ver a figura no arquivo original]. Adicionalmente, foram caracterizadas propriedades fotofísicas importantes desta nova sonda 3-AFA 11, entre as quais seus espectros eletrônicos de absorção e emissão de fluorescência, que obtiveram valores de λex a 320 nm e λem a 400 nm, respectivamente. Por fim, foi testado o potencial de acúmulo intracelular da sonda 3-AFA 11 em sistemas celulares tais como: eritrócitos infectados com Plasmodium chabaudi e amastigotas de Leishmania L. amazonensis, sendo possível observar em todos os casos a marcação fluorescente dos respectivos parasitas. / The use of fluorescent probes for labeling or detection of biomolecules of interest in different biological processes, has received much attention in biomedical, clinical testing and cell biology research. In general, these fluorescent probes are composed of small organic molecules, which have fluorescent features and ability to combine with these biomolecules. Thus, this work initially describes the synthesis of 2-aryl or 2,5-diarylfurans and thiophenes (3, 5, 7 and 9a-i) from organic species of tellurium (1, 4, 6 and 8) and potassium organotrifluoroborate salts (2a-i) by palladium catalyzed Suzuki-Miyaura crosscoupling reaction [see the figure in the original file]. After describe the synthesis of a unsymmetrical 2,5-diarylfuran derivative, the 2-(3-aminophenyl)-5-(4-methoxyphenyl)furan 11, which presents chemical and luminescent properties appropriate to act as a promising new fluorescent probes in processes of marking or biological detection. The synthesis of this new probe, also called 3-AFA (3-AnilylFuranAnisole), was performed from palladium catalyzed Suzuki-Miyaura cross-coupling reaction, between (3- aminophenyl) boronic acid 5e and 2-(butyltellanyl)-5-(4-metoxyphenyl)furan 10 in 65 % yields. This new probe 3-AFA 11 was combined with a series of Lamino acids 12a-l from a peptidic coupling reaction to obtain their products 13a-l in satisfactory yield. These combined products 13a-l show a potential for fluorescent marking of proteolitic enzymes [see the figure in the original file]. Additionally, important photo physical properties of this new probe 3-AFA 11 were characterized. These include their electronic spectra of absorption and fluorescence emission, who obtained values of λex to 320 nm and λem to 400 nm, respectively. Finally, we tested the potential of probe 3-AFA 11 for intracellular accumulation in cellular systems such as: erythrocytes infected with Plasmodium chabaudi and amastigotes of Leishmania L. amazonensis, in all cases the fluorescent uptake cellular of their parasites can be observed.