(107b) Guanidine/alcohol and Amidine/alcohol Switchable Solvent Mixtures

Organic solvents are a crucial part of chemistry on both a laboratory and an industrial scale. However, because solvents have very fixed properties, they often need to be removed and replaced between different steps of a reaction. This leads to an increase of economic cost and environmental impact for many processes. Developing a switchable solvent that can reversibly change its nature and properties at mild conditions would help solve this problem. Examples of solvents that consist of either a mixture of an amidine and alcohol or a guanidine and alcohol have been developed that form high polarity ionic liquids when exposed to CO2 at atmospheric pressure. Furthermore, these ionic liquids can be reversed back to a low polarity neutral form by exposure to nitrogen or mild heating. Such liquids have been used as a reaction medium utilizing their ?built-in? facile separation.