Some synthetic and mechanistic studies relating to biomimetic oxidation.

This thesis is largely concerned with the study of a cytochrome P-450 enzyme mimic consisting of an Iron porphyrin and iodosylbenzene. Chapter 1 consists of a review of the work that has been published on the above and other related metalloporphyrin biomimetic systems. The contents bear witness to the relatively recent interest in these particular enzyme mimics. A kinetic investigation forms the substance of the second chapter. The effect of structural and electronic changes on the iron porphyrin catalyst and the iodosylbenzene oxidant are measured in terms of their effect on the rate of cyclohexene oxidation. Other variables, such as the structure of the substrate and the nature of the solvent system, lead to a proposed mechanism. In Chapter 3 the iron porphyrin system is applied to 15,16-dihydrocyclopenta[a] phenanthren-17-one and its carcinogenic 11-methyl homologue. An attempt is made to selectively oxidise the terminal rings of the cyclopenta[a] phenanthrenes by Incorporating sterically bulky groups around the periphery of the iron porphyrin. The chemically active K-region remained the target for the majority of the iron porphyrins used, however some porphyrin substituents played an active role in encouraging the approach of the cyclopenta[a] phenanthrene substrate. Chemical modelling studies of the active site of the iron porphyrins and the question of steric hindrance as it relates to the approach of the cyclopenta[a] phenanthrenes are reported in Chapter 4