“…The only other complex that comes close to this binding mode is a zirconacyclopentane compound that possesses -H atoms, although -hydride elimination is hampered by the cyclic nature of the ligand (Hagadorn & Arnold, 1997). All the other structurally characterized derivatives show benzyl (Bazinet et al, 2003;Munslow et al, 2004;Hagadorn, 2001;Duncan et al, 2001;Walther et al, 1996;Coles & Hitchcock, 2003;Ong et al, 2003;Westmoreland et al, 2004) or methyl (Hagadorn & Arnold, 1997;Littke et al, 1998) groups attached to the group 4 metal.…”