摘要：

Noncovalent and reversible covalent interactions are of central importance to the fields of catalysis and supramolecular chemistry. The work presented in this thesis focuses on our interests in furthering the understanding and utility of halogen bonding (XB) and boron-diol interactions.;A review of organoboron acid-based catalysts is presented in Chapter 2. Their ability to function as Lewis acids and to activate carbonyl pronucleophiles, carboxylic acids and hydroxyl groups is discussed, alongside the advantages and limitations associated with their use as catalysts.;Chapter 3 describes the development of novel borinic acid catalysts for the regioselective functionalization of di- and polyols under mild reaction conditions. This work builds on the group's previous finding that diphenylborinic acid can reversibly bind to diols. Through the formation of a tetracoordinate 'ate'-compex, the bound oxygens are activated as nucleophiles. 9- Hetero-10-boraanthracene-derived borinic acids were found to be less prone to oxidative decomposition than diphenylborinic acid, thus lowering reaction times and improving catalyst turnover. Furthermore, the physical properties of the boraanthracenes were studied through X-ray crystallography, NMR, UV-vis and fluorescence spectroscopy.;Chapter 4 describes studies aimed at using 9-hetero-10-boraanthracenes as substrates for Suzuki-- Miyaura cross-couplings (SMCs). Using this methodology, benzannulated heterocycles were synthesized via a twofold SMC. Despite a slow transmetallation step, this process enabled the step- and atom-economial synthesis of medium-sized heterocycles.;Chapter 1 describes the development of tridentate halogen bond donor receptors that were used to assess the strengths of various XB interactions. By exploiting the chelate effect of these tridentate receptors, XB association constants varying by four orders of magnitude were obtained, enabling comparisons to other noncovalent interactions, such as hydrogen bonding and anion-pi interactions. Furthermore, free energy relationships between computed and experimental data were apparent over the wide range of electronically diverse donors studied.;Finally, Chapter 5 details our current approaches towards expanding the scope of electrophiles that can be used for borinic acid catalyzed diol functionalizations. Monoallylations of diols were achieved in high yields using Pd/B dual catalysis. We are currently expanding this concept towards the desymmetrization of meso-diols through the development of chiral Pd-ligands.

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