https://scholarworks.unist.ac.kr/handle/201301/17 2026-04-08T00:28:59Z https://scholarworks.unist.ac.kr/handle/201301/90924 Title: Design and Synthesis of Heteroatom-Containing Polycyclic Aromatic Hydrocarbons with B–N and B–O Bonds Author(s): Kim, Si-In Abstract: We developed a new synthetic strategy for iterative BO-containing acene derivatives. This approach is both simple and efficient, enabling two-ring expansion in only two steps: ipso-iodination directed by a trimethylsilyl group, followed by Suzuki cross-coupling and subsequent condensation for BO annulation. Repeating this cycle allowed the sequential introduction of BO units in a zigzag pattern along the acene edges. Through this strategy, we successfully synthesized anti-BO-acene derivatives. This methodology expands the structural diversity of acenes and provides fundamental insight into how BO unit incorporation modulates their electronic structures and photophysical properties. Overall, this study establishes a practical molecular design platform that overcomes previous synthetic limitations and highlights the potential of anti-BO-acene derivatives as promising candidates for next-generation organic electronic materials. Chapter 2: Synthesis of Triphenyl-fused Azaphenalenes Derivatives with Multiple Heteroatoms A triangular PAH, 1H-phenalene, first reported by Mayer in 1922, is composed of three fused rings sharing edges (Figure 10a).55 This molecule contains one sp³-hybridized carbon, which limits the extent of π-conjugation and results in non-aromatic behavior. In principle, while fully conjugated structures of 1H-phenalene can be generated as cationic, radical, or anionic intermediates, the inherent instability and ionic nature of these species make such approaches practically challenging.56 A more effective strategy involves the incorporation of heteroatoms such as nitrogen atom, allowing the formation of fully conjugated, neutral systems that maintain both electronic stability and planarity. From this analysis, the nitrogen-containing analogue azaphenalene was first reported by Windgassen in 1959 (Figure 10b).57 Figure 10. Chemical structures of (a) 1H-phenalene, (b) azaphenalene, (c) and (d) more nitrogen- containing azaphenalene derivatives. The lone pair electrons on the central nitrogen enables azaphenalene to achieve a 14 π-electron system, thereby restoring aromaticity and maintaining both planarity and continuous conjugation. Despite these advantages, studies on azaphenalene have remained limited due to synthetic challenges.58 Nevertheless, phenalene and its derivatives continue to serve as valuable model systems for investigating electronic structures.59,60 Recently, nitrogen-substituted azaphenalene derivatives have been developed (Figure 10c and d),61,62 attracting increasing attention for their tunable electronic properties and potential applications. In particular, tricycloquinazoline (Figure 10d), which is triphenyl- fused azaphenalene derivative, can be efficiently synthesized with high yields via a one-pot condensation reaction starting from 2-amino-1-benzonitrile as the precursor,61 providing a versatile platform for further functional studies (Figure 11a). Figure 11. (a) Synthetic method of tricycloquinazoline, (b) The proposed synthetic method of heteroatom-containing azaphenalene derivatives. In this study, tricycloquinazoline was selected as a model compound. Incorporation of nitrogen atoms into the phenalene framework enhances the overall structural stability, while its straightforward one-step synthesis further highlights its synthetic accessibility. This simple and efficient synthetic method through condensation, combined with the improved structural stability, inspired us to further explore the potential of this molecule. Based on this molecular platform, we aimed to tune the energy gap at the atomic level by replacing the central N–C–N unit with N–B–N or N–B–O units. BN substitution provides isoelectronic stabilization, whereas BO substitution introduces a larger electronegativity difference and a distinct dipole moment, thereby will be expected to impart unique optical and electronic properties.20–24 The transformation of boronic acids (–B(OH)2) into dichloroboranes (–BCl2) using SiCl4 has been previously reported.63,64 Building upon this precedent, we designed a cyclization reaction via electrophilic borylation, taking advantage of the electrophilic nature of electron-deficient boron centers. This approach, reminiscent of the efficient and straightforward synthesis of tricycloquinazoline, enables the facile incorporation of boron atoms into the molecular framework. Through this process, we envisioned that triphenyl-fused azaphenalene derivatives incorporating BN or BO units could be obtained. Herein, we present a straightforward one-pot strategy for synthesizing azaphenalene derivatives using boronic acid as the boron source, allowing controlled incorporation of BN or BO units into the model compound (Figure 11b). The resulting compounds were systematically characterized by spectroscopic and electrochemical techniques, revealing clear differences in their electronic structures and optical properties depending on the type of substitution. Notably, BO-azaphenalene exhibited promising performance in perovskite solar cells (PSCs), highlighting its potential for broader application in organic electronic devices such as OLEDs and OFETs. Major: Department of Chemistry 2026-01-31T15:00:00Z https://scholarworks.unist.ac.kr/handle/201301/88312 Title: Iterative Synthesis of BO-Acene Derivatives with Multiple BO Units at the Zigzag Edges Author(s): Jang, Jinuk Major: Department of Chemistry 2025-07-31T15:00:00Z https://scholarworks.unist.ac.kr/handle/201301/88311 Title: Stimuli-Responsive Self-Assembly Strategies for Spatiotemporal Modulation of Organelle Targeting Therapy Author(s): Lim, Chaelyeong Abstract: Supramolecular systems, formed through non-covalent interactions, are pivotal in mimicking the dynamic, self-organizing behavior of biological macromolecules such as proteins, nucleic acids, and lipids. These systems play a crucial role in cellular functions by enabling the precise regulation of biomolecular interactions that govern physiological processes. The diversity and adaptability of supramolecular chemistry allow for the design of systems that respond to specific biological stimuli, creating potential therapeutic strategies that address disease mechanisms. At the heart of this approach is the ability to control self-assembly processes, enabling the creation of functional nanostructures that interact with cellular components in a targeted manner. This versatility has led to the exploration of stimuli-responsive supramolecular systems that undergo structural transitions or reorganizations in response to internal cues, such as redox conditions or enzyme activity, as well as external signals like light. By leveraging these mechanisms, such systems can be tailored to selectively activate therapeutic interventions in diseased tissues, where microenvironmental conditions are significantly altered. This thesis explores two innovative approaches to leveraging supramolecular chemistry for therapeutic applications, focusing on stimuli-responsive systems. Chapter 2 focuses on an AIE-based monomer system that modulates mitochondrial dynamics via light-induced fission and fusion processes. Light exposure triggers AIE-induced ROS, which induce disulfide bond formation, leading to PISA inside mitochondria. This process results in the formation of nanostructures, inducing mitochondrial fission. Subsequent washing with fresh media restores mitochondria to their original state, suggesting a novel approach for controlling mitochondrial dynamics in response to external stimuli. The ability to manipulate mitochondrial morphology and function through this system offers potential therapeutic applications in diseases related to mitochondrial dysfunction. Chapter 3 develops a Transformable LYTAC system that utilizes enzyme-responsive self-assembly to enhance the degradation of pathological proteins. In this system, micelles undergo a transformation into fiber structures upon activation by ALP. This transformation increases the interaction range with target proteins and lysosome receptors, resulting in multi-interaction and high affinity, thereby enhancing the efficiency of TPD. The ability to switch between different self-assembled structures offers a mechanism for more effective targeting of disease-related proteins, presenting potential therapeutic applications for diseased or aging cells. Major: Department of Chemistry 2025-07-31T15:00:00Z https://scholarworks.unist.ac.kr/handle/201301/88310 Title: One-pot Synthesis of Large Area, Well-Ordered N-Doped Carbon Nanowalls (CNWs) on Cu(111) via High Temperature Electrochemistry Author(s): Kim, Dongwoo Major: Department of Chemistry 2025-07-31T15:00:00Z