Synthesis and Reactivity of Boron-Functionalized Carborane-Based Chalcogenides
Organochalcogen chemistry is a well-established field: organosulfur compounds find a wide variety of uses in synthetic chemistry; organoselenium and organotellurium compounds, despite being less prevalent than organosulfur compounds, have established niche uses in synthetic chemistry and are attracting a lot of research interest. Carboranes are three-dimensional boron-rich clusters with delocalized bonding analogous to the aromaticity of benzene and a steric profile similar to adamantane. These unique properties, along with their electronic tunability based on the chosen vertex of functionalization, give carboranes a variety of applications in fields such as medicinal chemistry and materials science. Ortho- and meta-Carborane clusters functionalized with chalcogen atoms at the electron rich B(9) position are relatively unexplored; there has been reports in the 1970’s-1980’s of the synthesis and basic reactivity of these clusters, as well as reports of some applications (Self-Assembled Monolayers, Boron Neutron Capture Therapy) for the sulfur-functionalized clusters, but that is all. In this thesis, the field of B(9)-functionalized carborane chalcogenides has been expanded in two ways: 1) new B(9)-S functionalized reagents have been synthesized and tested for their propensity to undergo B-S bond cleavage, a completely unexplored field in carboranes, and 2) the synthesis and reactivity of a variety of new B(9)-Se and B(9)-Te compounds has been discussed.