Reactions of tetrakis(trimethylsilylmethyl)hafnium with trimethylaluminum

Abstract Reactions between TiMe 4 , Cp 2 ZrMe 2 or Hf(CH 2 SiMe 3 ) 4 and AlMe 3 were investigated using conductivity measurements and 1 H NMR spectroscopy. Little change was observed in the conductivity of Hf(CH 2 SiMe 3 ) 4 /AlMe 3 or AlMe 3 /Cp 2 ZrMe 2 mixtures in dichloromethane relative to the molar conductivity of the reactants. In the presence of PEt 3 , a small increase in conductivity was observed for the latter solution. A 50-fold increase in the conductivity was observed in mixtures of TiMe 4 and AlMe 3 . Spectroscopic studies on mixtures of Hf(CH 2 SiMe 3 ) 4 and AlMe 3 were consistent with formation of a thermally unstable, alkyl bridged heterobimetallic complex, 2, present in a 5:1 ratio to the starting materials.