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1
Campbell, Patrick, and Patrick Campbell. "Hydrogen Storage Applications of 1,2-Azaborines." Thesis, University of Oregon, 2012. http://hdl.handle.net/1794/12555.
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The development of safe and efficient hydrogen storage materials will aid in the transition away from fossil fuels toward a renewable, hydrogen-based energy infrastructure. Boron-nitrogen (BN) containing materials have attracted much attention due to their high hydrogen storage capacity and fast kinetics of hydrogen release. Furthermore, computational studies predict that hydrogen storage materials based on the BN-heterocycle 1,2-azaborine may enable reversible H2 uptake and release, with little additional energy input. This thesis develops the basic science needed for a hydrogen storage platform based on BN-heterocycles such as 1,2-azaborine. Chapter I is a review of recent developments in azaborine chemistry. Chapter II describes a regeneration scheme from a "spent" 1,2-azaborine hydrogen storage material to "fully charged" fuel using molecular H2 and H-/H+ equivalents. Chapter III describes the experimental determination of the resonance stabilization energy of 1,2-azaborines using reaction calorimetry. Chapter IV explores the effect of boron-substitution on the rate and extent of hydrogen release from BN materials. Chapter V describes work on a project unrelated to hydrogen storage, the synthesis and electronic parameter determination of the first 1,2- azaborine-containing phosphine ligand analog.
This dissertation includes previously published and unpublished co-authored
material.
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Baggett, Andrew William. "New Strategies Enabling Diverse Functionalization of Aromatic 1,2-Azaborine Motifs." Thesis, Boston College, 2016. http://hdl.handle.net/2345/bc-ir:105027.
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Thesis advisor: Shih-Yuan Liu<br>Described herein are four projects focused on the elaboration of aromatic 1,2-azaborine core structures through late-stage functionalization strategies. In the first chapter, the gram scale, protecting group-free synthesis of the direct BN isostere of benzene is developed. This protocol is used to produce large quantities of pure 1,2-azaborine suitable for use in fundamental investigations. Second, the first general solution for the functionalization of the C4, C5, and C6 ring positions of 1,2-azaborines is described, featuring iridium catalyzed C-H borylation as the key strategy. Azaborine boronates produced via this method are successfully elaborated through cross coupling and oxidation to access azaborines that serve as N,N-ligands for electrophilic boron sources. The third project is an extension of the borylation/cross coupling project, and introduces the first polymer consisting of repeating azaborine units that displays highly efficient extension of conjugation along the azaborine chain. Finally, a copper catalyzed radical process is developed that enables removal of azaborine boron protecting groups during synthetic routes to simple azaborine targets of high interest<br>Thesis (PhD) — Boston College, 2016<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
3
Marwitz, Adam John Von 1981. "The chemistry of 1,2-dihydro-1,2-azaborine and nitrated lipids." Thesis, University of Oregon, 2010. http://hdl.handle.net/1794/11299.
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xxv, 468 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.<br>1,2-Dihydro-1,2-azaborine is a six-membered aromatic heterocycle that is related to the quintessential aromatic molecule, benzene, via the replacement of a CC fragment in benzene with an isoelectronic BN bond-pair. Like the benzene motif, 1,2-dihydro-1,2-azaborine derivatives could provide opportunities in fields ranging from medicine to materials. Recent breakthroughs in the synthesis of 1,2-dihydro-1,2-azaborine have led to a burgeoning interest in this relatively unexplored heterocycle. This dissertation describes the synthesis, characterization, and potential applications of novel 1,2-dihydro1,2-azaborines. Chapter I reviews the chemistry of monocyclic and polycyclic BN-heterocycles over the last fifty years. Chapter II introduces the synthesis of numerous boron-substituted 1,2-dihydro-1,2-azaborine derivatives from a versatile precursor. Chapter III discusses the first successful synthesis of the parent 1,2-dihydro-1,2-azaborine, which is isoelectronic with benzene itself. An examination of the chemistry of 1,2-dihydro-1,2-azaborine provides a direct comparison of its properties relative to benzene. Chapter IV discusses the synthesis and characterization of 1,2-dihydro-1,2-azaborines incorporated into phenylacetylenic scaffolds. Chapter V discusses unrelated work on nitrated lipids, which was performed under the guidance of Professor Bruce Branchaud. The chapter introduces the importance of nitrated lipids in a biological context and details the synthetic achievements in this field.
This dissertation includes previously published and unpublished co-authored material.<br>Committee in charge: Michael Haley, Chairperson, Chemistry;
Shih-Yuan Liu, Advisor, Chemistry;
David Tyler, Member, Chemistry;
Raghuveer Parthasarathy, Outside Member, Physics
4
Lamm, Ashley, and Ashley Lamm. "Fundamental Chemistry of 1,2-Dihydro-1,2-Azaborines." Thesis, University of Oregon, 2012. http://hdl.handle.net/1794/12514.
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Benzene and its derivatives are ubiquitous in chemical research, with applications ranging from material science to biomedical research. 1,2-Dihydro-1,2-azaborine is a benzene mimic which replaces a CC bond with a BN bond. The basic science and applications of 1,2-azaborines is relatively underdeveloped. This thesis expands the fundamental understanding of 1,2-azaborines. Chapter I describes the air and moisture stability of 1,2-azaborines. Chapter II introduces nucleophilic aromatic substitution reactions that the parent 1,2-dihydro-1,2-azaborine will undergo. Chapter III discusses a trimerization reaction that 1,2-dihydro-1,2-azaborine can perform, which is unique from benzene. Chapter IV examines a novel protection free synthesis of 1,2-azaborines, which provides a more direct route to functionalized 1,2-azaborines. Chapter V discusses the novel deprotection of the N-silicon using an amide, giving one of the first 1,2-azaborine pharmaceutical mimics. Finally, chapter VI summarized miscellaneous contributions I have made to the basic science of 1,2-azaborines.
This dissertation includes previously published and unpublished co-authored material.<br>10000-01-01
5
Brown, Alec Nathaniel. "Late-Stage Functionalization of 1,2-Dihydro-1,2-Azaborines." Thesis, Boston College, 2015. http://hdl.handle.net/2345/bc-ir:104564.
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Thesis advisor: Shih-Yuan Liu<br>Described herein are two distinct research projects focused on the development of metal-catalyzed late-stage functionalization strategies for 1,2-dihydro-1,2-azaborines separated into three chapters. The first chapter discusses the development, synthesis, and recent contributions to the field of azaborine chemistry. The second chapter details the development of rhodium catalyzed B-H bond activation for the synthesis of a new class of BN-stilbenes as well as the discovery of a novel B-H to B-Cl transformation that is successful both with B-H azaborines as well as other B-H containing compounds. The third chapter pertains to the development of a B-H and B-Cl tolerant C(3) functionalization strategy through the use of Negishi cross-coupling. Using this methodology, previously unreported isomers of BN-naphthalene and BN-indenyl have been synthesized and characterized<br>Thesis (PhD) — Boston College, 2015<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
6
Bentley, Sierra Kathleen. "Selective Direct Borylation and Late-Stage Functionalization of 1,2-Azaborines:." Thesis, Boston College, 2020. http://hdl.handle.net/2345/bc-ir:109014.
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Thesis advisor: Shih-Yuan Liu<br>Described herein is the development of a method to directly borylate the C5-position of monocyclic 1,2-azaborines without the use of a metal catalyst, kinetic resolution or directing group. This method tolerates different substitution on the boron as well as at the C3-position of the azaborine. A new BN-isostere of the drug molecule, felbinac, was synthesized to demonstrate the application of this method<br>Thesis (MS) — Boston College, 2020<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
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Armand, Jeremy Richard. "Late Stage Functionalization of 1,2-Azaborines for Application in Biomedical Research:." Thesis, Boston College, 2019. http://hdl.handle.net/2345/bc-ir:108646.
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Thesis advisor: Shih-Yuan . Liu<br>Chapter 1. Use of boron as a pharmacophore is as growing but still underdeveloped strategy for expanding chemical space in biomedical research. In addition to more established methods of incorporating boron in drug development, an attractive and emerging method of introducing boron into biologically active compounds is through boron-nitrogen containing heterocycles. In particular, the Liu group has focused on exploring the interactions of monocyclic 1,2-azaborines in biological space. In order to install complicated chemical functionality needed for further studies, methods for late stage functionalization of 1,2-azaborines must be developed. Described herein is a method for functionalizing 1,2-azaborine at the C3- and C5-positions, with bromine and iodine handles, respectively. Chapter 2. Described is the application of the turbo Grignard reaction to 1,2-azaborines bearing a B–Cl bond. The reaction utilizes iPrMgCl·LiCl to form aryl carbon nucleophiles and is tolerant of sensitive functional groups such as nitriles and esters. Development of the reaction obviates the need to use toxic organotin reagents to install aryl groups at the B-position that bear sensitive, electrophilic functionalities<br>Thesis (MS) — Boston College, 2019<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
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Zhang, Yuanzhe. "Pd/azaborine-biaryl phosphine complexes: reaction development, mechanistic analysis, and investigations into metal-ligand coordination dynamics." Thesis, Boston College, 2021. http://hdl.handle.net/2345/bc-ir:109152.
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Thesis advisor: Shih-Yuan Liu<br>Described herein are three research projects that focused on 1) the catalytic activities of Pd/azaborine-derived biary phosphine (Senphos) complexes in 1,3-enyne difunctionalization reactions and 2) the coordination behaviors of these Pd/Senphos complexes. In the first chapter, expansion of the substrate scope and mechanistic studies of the reported Pd/Senphos catalyzed site-, regio- and trans-selective hydroboration of 1,3- enynes are described. In the second chapter, the first intermolecular site-, regio- and transselective chloroboration and cyanoboration of enynes that are enabled by the Pd/Senphos catalytic system are presented. The cyanoboration products, namely vicinal boronsubstituted alkenylnitriles, are demonstrated as versatile synthetic building blocks. In the last chapter, the κ2-P-η2-B,C coordination behavior in a series of 1,2-, 1,3- and 1,4-Senphos ligated Pd(0) or Pd(II) complexes are evaluated based on solid-state structures and variable-temperature NMR measurements<br>Thesis (PhD) — Boston College, 2021<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
9
Deegan, Jonathan E. "Aryl and Alkyl Migration Strategies for the Functionalization and Application of 1,2-Azaborines:." Thesis, Boston College, 2019. http://hdl.handle.net/2345/bc-ir:108582.
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Thesis advisor: Shih-Yuan Liu<br>As BN-CC isosterism becomes an increasingly valuable strategy to expand chemical space and increase molecular diversity, methods for functionalizing and utilizing BN-heteroarenes remain limited in comparison to those for all-carbon arenes. Described herein are initial studies aimed at developing methods for the late-stage functionalization of substituted 1,2-azaborines through controlled aryl and alkyl migrations. Furthermore, investigations into the application of B-aryl and B-alkyl 1,2-azaborines as transmetalation reagents in Suzuki-Miyaura cross-coupling reactions are presented<br>Thesis (MS) — Boston College, 2019<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
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Thiedemann, Birk [Verfasser], Anne [Akademischer Betreuer] Staubitz, and Ulrich [Gutachter] Lüning. "Syntheses of Azaborine Polymers and Optimisation of Precursor Syntheses / Birk Thiedemann ; Gutachter: Ulrich Lüning ; Betreuer: Anne Staubitz." Kiel : Universitätsbibliothek Kiel, 2017. http://nbn-resolving.de/urn:nbn:de:gbv:8-diss-202962.
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11
McConnell, Cameron Reed. "Leveraging 1,2-Azaborine's Distinct Electronic Structure to Access New Building Blocks:." Thesis, Boston College, 2019. http://hdl.handle.net/2345/bc-ir:108607.
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Thesis advisor: Shih-Yuan Liu<br>Described herein are three projects that derive from in-depth studies of the distinct electronic structure of monocyclic 1,2-dihydro-1,2-azaborine (heretofore referred to as simply 1,2-azaborine). In the first chapter, the first comprehensive review of the late-stage functionalization methods available for 1,2-azaborines as well as their bicyclic and polycyclic (BN-PAH) counterparts is presented. In the second chapter, the development of a general method for both C4 and C5 functionalization based on the building block approach is described. The distinct electronic structure of 1,2-azaborine enables the chemical separation and further functionalization of C4 and C5 borylated isomers. In the second part, the C4, C5, and C6 isomers of BN-styrene analogues were prepared using the newly developed azaborine building blocks. The corresponding polymers were synthesized and extensively characterized in order to compare the effects of the BN-bond positioning relative to the polymer chain. In the fourth and final chapter, 1,2-azaborine-containing phosphine ligands featuring a P-B bond are synthesized. A comparative electronic structure analysis is performed between the BN-phosphine ligands and their direct all-carbon counterparts<br>Thesis (PhD) — Boston College, 2019<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
12
Motika, Stephen. "Diversifying Homogenous Au(I)-Catalysis through New Reaction Discovery." Scholar Commons, 2017. http://scholarcommons.usf.edu/etd/6911.
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Homogenous Au(I)-catalysis has become a valuable synthetic tool to activate a host of unsaturated carbon functional groups towards nucleophilic addition. Over the course of the past two decades, many have embarked on new journeys within this field. Notably, the advancements in this field hinge on the development of new ligand systems that impart novel reactivity at the metal. Our group has focused on this area, as we have successfully demonstrated the utility of 1,2,3-triazoles as ligands for gold and a host of other transition metals and Lewis acids. With respect to gold catalysis, these ligands enhance the stability of the metal center, thus inhibiting typical reductive decomposition pathways that have plagued this field. The enhanced stability comes with a price though as higher temperatures can be required. We’ve addressed this challenge by discovering an interesting synergy between triazole-gold and Lewis acids, allowing us to overcome the lower reactivity of these catalysts.
During my time as a graduate student, I have focused heavily on enlisting these catalytic systems for new reaction discovery. In my first experimental chapter, I was able to develop an interesting reaction cascade in which triazole-gold and secondary amine catalysts were used. I started with a well-known gold-catalyzed Claisen rearrangement of propargyl vinyl ether, yielding functionalized allenes. The identical oxidation state between these allenes and synthetically appealing dienals was an impetus to develop a new isomerization strategy. After screening various conditions, I was able to successfully execute this design.
Most of the work I have been involved in over the past two years has surrounded a gold-catalyzed hydroboration to yield interesting hetercocycles containing a N-B bond. The N-B bond offers some unique properties as it is isoelectronic to a C-C double bond. Despite the simplicity in this design, it would become apparent early on in this research that mitigating the reducing strength of the starting materials was absolutely critical. Starting materials that were too strongly reducing led to rapid catalyst decomposition. Through thorough reaction screening, we have been able to identify a catalytic system that performs extremely well in this context. Ultimately, our goal in this work is to access 1,2-azaborines, which are isosteres of benzene. This compound exhibits aromaticity, as determined through structural and quantitative analyses by several groups. However, subtle differences in properties between the azaborine and benzene, such as its polarity, have intrigued many researchers across various disciplines. Moreover, the ubiquity of its carbonaceous parent in biological systems has prompted many to pursue new synthetic routes to access 1,2-azaborines.
13
Lee, Hyelee. "Site-Selective Reactions Via Scaffolding Catalysis & Synthesis and Binding Study of 1,2-Azaborines." Thesis, Boston College, 2017. http://hdl.handle.net/2345/bc-ir:107562.
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Thesis advisor: Kian L. Tan<br>Thesis advisor: Shih-Yuan Liu<br>Chapter 1. In the Tan laboratory, we developed synthetic methods to control reaction selectivity (regio-, stereo-, and site-selectivity) using scaffolding catalysis. Our strategy utilizes directing groups that induce intramolecularity through the formation of a labile covalent bond between the substrate and a binding site in a catalytic system. In the first part, we described site-selective functionalization of various carbohydrates and complex polyhydroxylated molecules which contain cis-1,2-diol motif using a chiral organic scaffold. In the second part, meta-selective C–H functionalization of arenes was demonstrated. High meta-selectivity was achieved by the use of a nitrile-based silyl tether which is cleavable and recyclable. Chapter 2. In the Liu laboratory, we focuses on studies of boron-nitrogen containing heterocycles. In this chapter, synthesis of 1,2-azaborines and their binding study with T4 lysozyme mutants were described. Specifically, we directly compared binding of NH-containing 1,2-azaborines and their carbonaceous analogs to probe hydrogen bonding interaction between the NH group of azaborine and a carbonyl oxygen of protein residue. Structural and thermodynamic analysis provided us the first evidence of H-bonding of azaborines with a biological macromolecule. Chapter 3. Described are the synthesis of regioisomers of ethyl-substituted 1,2-azaborines and their binding thermodynamics to T4 lysozyme mutants. To access the azaborine ligands used in the binding study, we developed synthetic methods for regioselective functionalization of six positions of 1,2-azaborines. Isothermal titration calorimetry experiments showed differences in binding free energy for regioisomers to the L99A T4 lysozyme. This result could originate from electronic differences of the isosteric ligands inducing dipole-dipole interaction between ligand and surrounding protein residues or it may be from local dipolar interactions. Chapter 4. A general method for late-stage N-functionalization of 1,2-azaborines is described to afford libraries of BN-containing complex molecules. The chemical transformations include electrophilic substitution reactions, N–C(sp2) bond forming reactions under Buchwald-Hartwig amination conditions, and N–C(sp) bond forming reactions using copper-catalyzed N-alkynylation. As applications in materials science and medicinal chemistry, synthesis of the first parental BN isostere of trans-stilbene and lisdexamfetamine derivative is described utilizing the methodology developed in this work<br>Thesis (PhD) — Boston College, 2017<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
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Aleotti, Flavia. "A 2-pyridyl-2,1-borazaronaphthalene derivative as forefather of a new class of bidentate ligands: synthesis and application in luminescent Ir(III) complexes." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13877/.
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Borazaro compounds (or azaborines) are aromatic compounds in which a C=C unit is replaced by an isoelectronic B-N unit. The possibility to generate chemical diversity has led to an increasing interest in azaborines, especially in the fields of biomedical research and optoelectonics. In particular, Dewar’s synthesis of borazaronaphthalene is a common starting step to obtain different 1,2-azaborines via nucleophilic substitution on the boron atom. Here we present the synthesis of a novel 1,2-azaborine (i.e. 4-methyl-2-(pyridin-2-yl)-2,1-borazaronaphthalene, named FAAH) via functionalization of 2-chloro-4-methyl-2,1-borazaronaphthalene with a 2-pyridyl unit. FAAH can be used as an anionic bidentate ligand for transition metal complexes, since it can chelate the metal center with both the pyridine and the azaborine nitrogen atoms. FAAH was used for the synthesis of a series of neutral luminescent Ir(III) complexes (named FAV, FAB and FAR) of general formula [Ir(C^N )2(FAA)], where C^N indicates three different cyclometalating ligands: i.e. 2-phenylpyridine in the case of FAV; 2-(2,4-difluorophenyl)pyridine in the case of FAB; 2-methyl-3-phenylquinoxaline in the case of FAR. The reaction yields are quite low, however it was always possible to characterize all the compounds by means of NMR spectroscopy. A complete photophysical and theoretical characterization is also presented. FAAH displays a good chemical stability and a high photoluminescence quantum yield (up to 28 % in solution). On the contrary, the Iridium complexes undergo degradation over time in solution. Despite this stability problem, it was possible to get a good understanding of the photophysics of the three complexes: the emission of both FAV and FAB is observed around 500 nm and arises from a 3LC state centered on the azaborine ligand. In the case of FAR, the emitting state is basically 3MLCT/3LLCT in nature and the resulting broad and unstructured emission band is centered around 700 nm.
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Boknevitz, Katherine Lynn Michelle. "Synthesis and Characterization of BN-tryptophan and its Incorporation into Proteins & the Cation-π Binding Ability of BN-indole:". Thesis, Boston College, 2020. http://hdl.handle.net/2345/bc-ir:108710.
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Thesis advisor: Shih-Yuan Liu<br>Described herein are two projects on the application and effects of BN/CC isosterism on indole-containing compounds. In the first chapter, the synthetic route to an unnatural boron and nitrogen-containing analogue of tryptophan (BN-tryptophan) via late-stage functionalization of BN-indole is disclosed and its spectroscopic properties are reported with respect to the natural amino acid, tryptophan. The incorporation of BN-tryptophan into proteins expressed in E. coli using selective pressure incorporation, a residue specific method of unnatural amino acid incorporation, is then reported and its reactivity and fluorescence in the proteins characterized. In the second chapter, the synthesis of a BN-indole-containing aromatic scaffold is reported and the cation-π binding ability characterized by nuclear magnetic resonance (NMR) monitored titrations is disclosed. The resulting chemical shifts were analyzed using a non-linear curve fitting procedure and the extracted association constants (Ka’s) compared with the natural indole scaffold. Computations were also performed to support the titration results<br>Thesis (PhD) — Boston College, 2020<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
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Ishibashi, Jacob Shotaro Afaga. "BN Isosteres of Acenes for Potential Applications in Optoelectronic Devices." Thesis, Boston College, 2017. http://hdl.handle.net/2345/bc-ir:107613.
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Thesis advisor: Shih-Yuan Liu<br>This dissertation describes progress in the field of polycyclic boron- nitrogen-containing systems, especially for potential application in organic-based optoelectronic devices and hydrogen storage materials. The replacement of a BN unit for a CC unit organic compounds (BN/CC isosterism) can have a profound effect on the electronic structure and even function of a given molecular topology without changing its physical structure very much. Direct comparison between a BN-containing molecule and its direct all-carbon analogue is crucial to establishing the origin of these differences. The synthesis and optoelectronic characterization of boron- nitrogen-containing analogues of naphthalene, anthracene, and tetracene are disclosed. Also examined herein is the aromatic Claisen rearrangement applied to an azaboryl allyl ether. Finally, the chemistry of saturated BN heterocycles, including an iridium-catalyzed transfer dehydrogenation method for synthesizing BN-fused azaborines. Also disclosed is the actual application of these cyclic amine-boranes in supplying hydrogen for a proton exchange membrane (PEM) fuel cell<br>Thesis (PhD) — Boston College, 2017<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Chemistry
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Boffa, Maria. "Atropisomeric 1,2-dibenzoazaborines: Synthesis and Dynamic Studies." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/16117/.
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In this thesis project we have studied new atropisomeric molecules that have a nitrogen-boron bond in an aromatic cyclic system, namely the 1,2-dibenzoazaborine structure. We have synthesized molecules that have a stereogenic boron-aryl axis with different steric hindrance in the ortho position of the aryl ring (compounds 5). The synthesis reaction was optimized for compound 5a and then we introduced a chirality probe to follow the dynamic process by NMR (e.g. an ethyl group in product 5b and an isopropyl group in the product 5c). We have analyzed the molecules with NMR spectroscopy at variable temperature (VT), dynamic HPLC and kinetics studies to determinate the racemization energy barrier. Where possible (compound 5d), we have assigned the absolute configuration of the atropisomers by ECD (Electronic Circular Dichroism) methods and by TD-DFT (Time Dependent – Density Functional Theory) calculation.
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Mercanti, Elia. "Synthesis and dynamic study of atropisomeric compounds containing boron-carbon bond." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10067/.
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In this thesis we studied the stereodynamic behavior of 1,2-azaborines variously substituted on boron (7a, 7b, 13). Depending on the hindrance of the asymmetric aryl substituent the resulting conformations could be stereolabile or configurationally stable. Through dynamic NMR and lineshape simulation, the energy rotational barriers of the different conformers are obtained. When the barrier is higher than 22-23 kcal/mol stable atropisomers that are fisically separable could be obtained (case of compound 13) and the free activation energy barrier is determinable by kinetic analysis. Absolute configuration of two atropisomers were assigned by comparison between computational calculations and experimental ECD. Isosteric compound 21 is then synthesized in order to compare the rotational barrier around B-Caryl with the one around Cnaphth-Caryl bond.
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Lo, Shih-Han, and 羅仕翰. "Design and Synthesis of 1,4-Azaborine derivatives as Blue and Green TADF Emitters." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/87b6nz.
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