Selected highlights in the application of ion-exchangers as supports for reagents in organic synthesis

The development of cleaner and more efficient synthetic routes to minimise environmental damage has been approached in many ways. Amongst these are: improved catalytic methods, solvent free reactions, reactions employing water as the solvent, the application of supercritical fluids, new asymmetric methods to minimise the production of unwanted isomers and atom-efficient synthesis. In all of these cases, the focus is to reduce the amount of materials required to perform the desired synthetic step, to obtain products requiring the minimum amount of expensive and/or complex purification steps, and therefore to reduce waste. The use of supported reagents to achieve a variety of useful organic transformations, whilst achieving at least some of these objectives, is the object of this review.