The synthesis, reactivity, and peripheral functionalization of corroles

Corroles are unusual macrocycles that often exhibit chemical reactivity that is distinct from their closely related porphyrin cousins. Standard organic transformations with corroles often result in the formation of unexpected products. A survey of synthetic methods for the preparation of both meso-substituted and beta-substituted corroles will give an overview of the different synthetic strategies. This review provides a comprehensive description of the chemical reactivity and functionalization of corroles, focusing especially on reactions at the periphery of the macrocycle. Formylation, nitration, bromination and chlorosulfonation reactions will be explored in detail. In addition, demetalation processes, reactivity of the N-pyrrolic nitrogens and the lability of the macrocycle ring toward expansion and ring-opening reactions will be discussed. Finally, the synthesis of super-structured (picket-fence, capped, and strapped) corroles and isocorroles will be surveyed.