Chiral templates definition

By definition, a chiral auxiliary differs from a chiral template in that the auxiliary is capable of being recycled after the desired asymmetric reaction. Hence, chiral templates will not be included in this chapter. The uses of a chiral moiety as a ligand for a reagent have also been excluded. 

In some instances recycling of a template may be feasible but not straightforward, For example, a chiral auxiliary may involve some templating aspects, and by definition is always separated from the final product. However, the form in which the auxiliary appears at the end of the reaction may be very different to its original structure, and elaborate chemistry may be required to re-establish that structure, far more elaborate than worthwhile. 

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