Boranes as an effective starting point in boron mediated reactions

Abstract

Boranes made up of boron and hydrogen atoms, are fascinating compounds known for their diverse structures and high reactivity. Because of these properties, they play important roles in various chemical transformations—ranging from reduction reactions and hydride transfers to catalysis in polymerization and cross-coupling processes. N-heterocyclic carbenes (NHCs), which are strong electron donors, are often used as ligands to stabilize reactive species, not only in transition metal chemistry but also in main group systems like boron. When NHCs form adducts with boranes, the resulting compounds are electrophilic and can undergo interesting acid-base reactions. Building on this, introducing an extra carbon at the 2-position of the NHC ring leads to N-heterocyclic olefins (NHOs), which are even more nucleophilic and tunable than NHCs. In NHO–boranes, the alkene group donates electron density to the boron center, making it more reactive and opening the door to new types of reactivity. In this thesis, I explore the synthesis of NHO–borane adducts and examine how they behave in acid–base reactions. Through this work, I aim to contribute to a better understanding of how these systems function and how we might harness them to design new, more versatile compounds in main-group chemistry.