Stoichiometric reactions of NacNacAlMe2 with [(Base)H][B(C6F5)4] also were performed. These afforded the cationic aluminum complexes cleanly for base = DMT and Et3N via methane elimination (Figure ). The protonolysis reactivity again correlates with the relative Brønsted acidity of the ammonium salts, with 15a forming within 1 h at room temperature, while the Et3N derivative, 15b, was formed fully only after heating for a prolonged period at 50 °C. No intermediates were observed during any of these protonolysis reactions.