Ligand exchange and alkyl abstraction involving (perfluoroaryl)boranes and -alanes with aluminum and gallium alkyls

Reaction between M(C6F5)(3) (M = B, Al) and AlR3 in hydrocarbons leads to facile aryl/alkyl group exchange and formation of aluminum dimers, while reaction of(perfluoroaryl)boranes B(C6F5)(3) and B(C12F9)(3) with AlR3 (R = Me, Et, octyl) or GaMe3 in ether solvents produces alumocenium or gallocenium berates. Neutral aluminum dimers and cationic alumocenium species have been found to be very effective as catalyst activators in ethylene/1-octene copolymerization.