Abstract: The first examples of mononuclear manganese(V) and chromium(V) imido corrole complexes were previously reported. The synthetic methodology relied upon the interception of an aryl nitrene, generated through the thermal and photochemical decomposition of the corresponding azide. A detailed kinetic and mechanistic study of NR group transfer from the imido complex derived from trichlorophenyl azide to various phosphines is presented in chapter 1. Different kinetic behavior of alkylphosphines from arylphosphines was observed Modification of the corrole ligand by introducing bromine atoms in the β-pyrrole positions had a pronounced effect on the complexes reactivity and a substantial positive shift in the MnV/IV redox couple. Additionally, a structural analysis of the less reactive chromium analogs was done. Shorter metal-nitrogen pyrrole distances and larger metal out-of-plane displacements were obtained for the imido complex derived from mesityl azide relative to a chromium(IV) oxo porphyrin but within the ranges displayed by other high valent corrole complexes. Their EPR spectra are very similar to chromium(V) nitrido complexes at both room temperature and 93 K. The design and progress towards the synthesis of a novel water-soluble hemicarcerand have been described in chapter 2. It contains resorcinarene-based cavitands with pyridine moieties in the linker groups and methyl pendant groups. Favorable complexation energies were obtained via molecular mechanics calculations for this hemicarcerand and its pyridinium acetate derivative with organic molecules, metal complexes and anions. This suggests that this hemicarcerand holds great promise as a host compound for these guest molecules. The current synthetic approach involved isolating the chloro derivative of the cavitand tetrol and then attempting the coupling reaction with more tetrol in the presence of different templates. The design and syntheses of two novel cavitand-based receptor molecules have been described in chapter 3. The first receptor contains a cyclic array of pyridine moieties and was found to display recognition properties towards acids but only if proton transfer between receptor and substrate was facilitated. Carboxylate recognition was displayed by the second receptor, which contains a cyclic array of pyridinium moieties.