Physical organic chemistry

Physical organic chemistry – the study of the interplay between structure and reactivity in organic molecules – underpins organic chemistry, and we cannot imagine organic chemistry as a subject without knowledge of mechanism and reactivity. It is sometimes thought that the golden age of ‘physical organic chemistry’ was in the 20th century, when systematic information about mechanism first burst onto the scene. Certainly the impact of early knowledge of mechanism of fundamental aliphatic substitution reactions, among others, was enormous, but our knowledge of reactivity and mechanism has continued to progress and deepen enormously ever since and this has been reflected in a number of Nobel Prizes in Chemistry. In an area of particular interest to me, the transformation of radical chemistry from being an almost impenetrable area to one that can be usefully harnessed even in synthetic applications, has been extraordinary – this transformation has been relatively recent and has been principally dependent on the accurate determination of kinetics of radical reactions.