Formation and Structure of [Cp2Zr(CH3)OAl(CH3)2]2 — a Neutral Dimethylzirconocene/Alumoxane Adduct

Abstract

Trimethylaluminum adds to cyclotrimeric zirconocene oxide [Cp2ZrO]3 to give the cyclodimeric mixed metal complex [Cp2Zr(CH3)OAl(CH3)2]2 (3a-dimer) featuring a central Al2O2 containing four-membered ring system. Complex 3a-dimer crystallizes in space group P21/c with cell parameters a = 8.3974(8), b = 8.6509(7), c = 19.718(1) Å, β = 97.36(1)°, Ζ = 2, R = 0.029, Rw = 0.038. With methylalumoxane 3a-dimer gives an active catalyst (Zr: Al ≈1:8) for ethylene polymerization.