Treatment of the neutral trimethyl compounds Cp*MMe 3 (M ) Ti, Zr, Hf) with the highly electrophilic borane B(C 6 F 5 ) 3 in methylene chloride in the presence of various arenes results in methyl carbanion abstraction and coordination of the arene to form complexes of the type [Cp*MMe 2 (η 6 -arene)][MeB(C 6 F 5 ) 3 ] (M ) Ti, Zr, Hf; arene ) benzene, toluene, m-and p-xylene, anisole, styrene, mesitylene). Indications of relative metal-arene affinities have been gleaned from a variety of low-temperature 1 H NMR experiments, and it seems that both steric and electronic factors play significant roles in determining stabilities. The crystal and molecular structures of [Cp*HfMe 2 (η 6 -toluene)][MeB(C 6 F 5 ) 3 ] have been determined; as anticipated, there are no significant contacts between anion and cation, and the latter assumes a bent-metallocene type of structure.