Imine Azaenolates: Synthesis, Reactivity, and Outlook

Azaenolates are, quite simply, the aza variant of enolates. Compared to their oxygen counterparts, additional control of the reactivity of azaenolates can be achieved by altering the substituent on the nitrogen atom as well as the metal counterion. Since the seminal examples reported in the early 1960s, azaenolates of various metals have been shown to react with a diverse set of electrophilic partners, including challenging electrophiles such as alkyl fluorides, epoxides, and oxetanes. This review describes in detail the current state of the art of the chemistry of azaenolates derived from imines, with a particular focus on the comparison of the reactivity exhibited with different metal counterions.