Highly selective propylene dimerization catalyzed by C 1 ‐symmetric zirconocene complexes

A series of ethylene‐bridged C 1 ‐symmetric ansa ‐(3‐ R ‐indenyl)(fluorenyl) zirconocene complexes ( 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ) incorporating a pendant arene substituent on the 3‐position of indenyl ring have been synthesized. The structure of complex 4 was further confirmed by X‐ray diffraction analysis. When activated with methylaluminoxane, four sterically less encumbered complexes 1 , 2 , 4 and 5 could catalyze the dimerization of propylene in toluene at 100°C to afford 2‐methyl‐1‐pentene with high selectivities up to 95.7–98.4% and moderate activities of 2.00 × 10 4 to 7.89 × 10 4  g (mol‐Zr⋅h) −1 . Copyright © 2014 John Wiley & Sons, Ltd.