Mechanisms and Chemical Reaction

Abstract

This chapter explores both the nature of mechanisms and their role in understanding chemical reactions. Particularly, it focuses on organic chemistry. By focusing on mechanisms in organic chemistry, the contrast between the nature and role of mechanisms in chemistry and biology can be emphasized. Biological mechanisms have been the focus of much recent philosophical work on the nature and explanatory role of mechanisms. Therefore the philosophical interest and importance of mechanisms in chemistry will derive principally from any significant differences between mechanisms in chemistry and their better-studied counterparts in biology. Understanding organic chemistry involves being capable not only of explaining and sometimes predicting important features of organic chemical reactions, but also of designing novel reactions or sequences of reactions for producing particular organic molecules. The chapter characterizes what chemists mean when they use the term “mechanism”, and offer a brief general account of how mechanisms contribute to the understanding of organic chemistry. Subsequently an example of how a reaction mechanism is established and evolves in the face of increasing experimental evidence is presented. This is followed by some more specific reflections on the role of these theoretical devices in approaching the fundamental problems of organic chemistry.