The chemistry of 2-oxazolines (1985–present)

2-Oxazolines have permeated numerous sub-disciplines in synthetic organic chemistry in the 100 years since their discovery. This versatile heterocycle has served as protecting group, coordinating ligand, and activating moiety, often exhibiting all of these characteristics in a single transformation. The well-defined reactivity of chiral oxazolines has given rise to numerous highly efficient strategies for asymmetric synthesis including their use as ligands in asymmetric catalysis. Various unique properties have dictated their use in a multitude of dissimilar applications: as monomers in polymer production, as moderators in analytical processes, and as conformationally rigid peptide mimics in medicinal chemistry. Even natural systems have chosen to incorporate oxazolines into their chemical arsenal, as evidenced by the rapidly growing number of identified natural products and their attendant pharmacological properties. Future studies will undoubtedly uncover unexpected properties and applications. The number of important publications detailing oxazoline-related chemistry is growing, suggesting that research in this area, as in synthetic organic chemistry in general, has yet to mature.