Intramolecular C–N bond activation by a transient boryl anion

Abstract

Using a flexible diamido framework, a bulky boron bromide has been prepared as a precusor to a boryl anion with an extremely wide N–B–N angle. Reduction of the compound with lithium metal resulted in intramolecular C–N bond activation and migration of an aryl group onto the boron centre. Reaction of the boron bromide with K[FeCp(CO)₂] resulted in nucleophilic reactivity of a carbonyl oxygen and the cooperative activation of CO.