Thermodynamic and Kinetic Effects
The interplay between thermodynamic and kinetic effects is very important, and as such it is possible to spend vast amounts of time and effort on it. The principal guideline is that reversible reactions are governed by thermodynamic considerations, while irreversible reactions are controlled by kinetic factors. As with thermodynamic factors, it is possible to spend a great deal of time and effort in understanding the kinetic factors that affect a reaction. In particular, it is possible to use some very elaborate mathematical models, which are very elegant, but tend to be rather off-putting to the uninitiated. However, there are several very useful guidelines that may be used to advantage without any need to have a detailed understanding of the underlying mathematics. The chapter presents a few more examples in which enthalpy has a large effect and considers the formation of a six-membered ring. It also looks at the formation of a five-membered ring from an aliphatic pentane molecule.