If a satisfactory protective group has not been located, the chemist has a number
of alternatives: Rearrange the order of some of the steps in the synthetic scheme
so that a functional group no longer requires protection or a protective group that
was reactive in the original scheme is now stable; redesign the synthesis, possibly
making use of latent functionality26 (i.e., a functional group in a precursor form;
e.g., anisole as a precursor of cyclohexanone). Or, it may be necessary to include
the synthesis of a new protective group in the overall plan or better yet, design new
chemistry that avoids the use of a protective group.