School of Science Department of Chemistry 5 New Methodologies for Organoborane Synthesis Supervisor: QUAN Yangjian / CHEM Student: CHANG Vincent / CHEM Course: UROP 1000, Summer This research Paper aims to give an in-depth analysis in molecular modification via the implementation of the elemental Boron. Molecular modification through bioisosteric replacement is a powerful strategy for enhancing the structural and functional complexity of drug candidates. This research puts effort in emphasizing the significance of molecular modification in designing drug molecules and their related derivatives. The incentive for developing new methodologies for the synthesis of similar Bio-active drugs is because the discovery and development of drugs are crucial to humanity, being able to provide new methods of synthesis contributes greatly to the human society. Our research has attempted to perform Bio isosteric replacement which is to change a fragment in a bioactive molecule with its analogue. This complements the traditional high throughput screening process, often highlighting improved efficiency. In medicinal Chemistry, Bioisosteres are chemical substituents or groups with similar physical or chemical properties that produces broadly similar biological properties in the same chemical compound. In drug design, the purpose of exchanging one bio isostere for another is to enhance the desired biological properties of a compound without making significant changes in the chemical structure. Among different types of Bioisosteric analogues, the boron-based ones stand out and it worths for an in-depth research on synthesizing new organoborane compounds. Due to this kind of reason, we have selected Borane compounds to undergo molecular modification. New Methodologies for Organoborane Synthesis Supervisor: QUAN Yangjian / CHEM Student: GAO Bin / CHEM Course: UROP 2100, Summer N-Heterocyclic carbene boranes exhibit distinct reactivities and stabilities compared to traditional boraneLewis base adducts (BH3•THF, BH3•NMe3, etc.). This is attributed to the presence of a π-system that stabilizes the Lewis acid-base interaction within the compound, preventing dissociation even at high temperatures (above 100 °C) and making them less sensitive to air and moisture. In this project, different kinds of N‐ Heterocyclic Carbene Boranes were synthesized to explore new methodologies for developing novel boron compounds. Three synthesis methods were employed: reflux of imidazolium salt with NaBH4, carbene generation in situ through deprotonation of imidazolium salt, and carbene formation via reduction of thiourea with potassium. Additionally, a novel recrystallization method was developed to further refine the synthesis process.
RkJQdWJsaXNoZXIy NDk5Njg=