School of Science Department of Chemistry 7 Borane Functionalization via Boryl Radical Supervisor: QUAN Yangjian / CHEM Student: CHEN Chuanxi / CHEM Course: UROP 1100, Summer Chain-walking methodology in organoboron chemistry helps scientists to achieve the functionalization of remote, inactivated C-H bonds. This strategy involves the migration of a boron-containing group along a carbon skeleton, which are often catalyzed by transition metals like cobalt, nickel, or palladium. The process occurs through mechanisms involving β-hydride elimination and re-insertion steps, and has already achieved selectivity by both thermodynamics and kinetics. Our focus is the use of metal-free borenium ions to catalyze similar transformations via hydride shifts, which is also a recent focus. One of the applications of this “isomerization-functionalization” approach is the conversion of internal olefins into terminal alkylboronates, which are highly useful intermediate to generate diols, amides, and other potential medicine structures. This opens a new chapter of synthetic pathways to complex molecules. Borane Functionalization via Boryl Radical Supervisor: QUAN Yangjian / CHEM Student: XU Yinghe / CHEM Course: UROP 2100, Fall Initiated a year ago, the investigation of the boron radical ( − 2+ ̇ ) on electron-deficient alkynes are carried out with preliminary results. Although our reaction system is advanced in the deficient of heavy metals, the selectivity of the product (E/Z ratio < 10:1) is concerning. Efforts are made in screening the reaction conditions, e.g. wavelength of the light source or the solvents, however, they all failed in achieving expected selectivity. To screen for one major product, we adopted a novel strategy, energy transfer (EnT). While screening was carrying, we discovered that a similar reaction system has already been reported. Although the substrates and the HAT catalyst are different, the extremely similarity of our system to theirs sparked reflection on the current research habits. To avoid the embarrassing situation and schedule experiments more efficiently, some protocols are summarized in this report. Design, Synthesis, and Applications of New Metal-Organic Frameworks Supervisor: QUAN Yangjian / CHEM Student: NGUYEN Kim Giang / CHEM Course: UROP 1100, Summer Covalent Organic Frameworks (COFs) are emerging as versatile platforms for photoredox catalysis, leveraging their tunable architectures and photochemical properties. This report explores novel COFs functionalized with multi-phenyl ligands bearing hydroxyl (-OH) groups, designed to enhance photoredox efficiency through improved light absorption and charge transfer. The ligands’ extended π-conjugation and hydroxyl moieties facilitate single electron transfer (SET) processes for organic transformations. Through synthetic design, structural characterization, and mechanistic exploration, this work elucidates the role of phenyl-linked hydroxyl groups in optimizing COF performance. The COFs enable selective C-H bond activation and radical-mediated reactions, providing an environmentally benign alternative to homogeneous catalysts. Future experimental validation will assess their scalability in eco-friendly methodologies.
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