||The attempted synthesis of three target zirconium catalyst compounds to be used in polymerization of ethylene and propylene will be described. All three zirconium ansa -metallocenes are novel. The inclusion of substituents (trimethylsilyl or t -butyl) as well as linkers (alkene or phosphine) on our target complexes is designed to make the catalysts regioselective (favoring 2,1-monomer insertions). For future work, we shall especially target (a) the relationship between regioselectivity and catalyst symmetry and (b) aptitude of these zirconium ansa -metallocenes toward polymerization (i.e. polymerization activity and polymer molecular weight). These are the objectives of the following research.