Cyclohexyl[trans-1,2-bis(1-indenyl)]zirkonium(IV)dichlorid: Ein chiraler polymerisationskatalysator mit stereochemisch starrer Brücke

Chiral trans-1,2-dimesylcyclohexane (1) reacts with indenylsodium to give trans-1,2-diindenylcyclohexane (2). This ligand precursor was used to prepare a mixture of diastereomeric cyclohexyl-[trans-1,2-bis(1-indenyl)]zirconium(IV) dichlorides (3). In contrast to ethylenebis(1-indenyl) zirconium(IV) dichloride (4), compound 3 catalyses the polymerization of propene with high stereoselectivity, even at polymerization temperatures above 50°C.