The Chemistry of Amino Imino Boranes

Dicoordinated boron compounds can no longer be considered as “exotic” species in boron chemistry: this is proved by the extensive chemistry of bis(dialkylamino)boron(1+) ions, alkylidene boranes, and imino boranes. The latter are characterized by high reactivity and chemical versatility. A special position is taken by amino imino boranes, whose chemistry is reported here. The presence of an amino group enhances the reactivity of imino boranes on the one hand and increases their kinetic stability on the other. New types of diamino boranes accessible via amino imino boranes often undergo intramolecular ring closure. These heterocycles are well suited to generate new types of cations of boron. Cycloaddition reactions using amino imino boranes open up a new heterocyclic chemistry of boron. The chemistry of N ‐functional amino imino boranes, which is still its infancy, shows much promise.