| abstract |
An organometallic compound obtainable by contacting a) a compound having the following formula (I), wherein R?a, Rb, Rc and Rd¿ equal to or different form each other are hydrocarbon groups b) a Lewis acid of formula (II): MtR13 wherein Mt is a metal belonging to Group 13 of the Periodic Table of the Elements (IUPAC); R1, equal to or different from each other, are selected from the group consisting of halogen, halogenated C¿6?-C20 aryl and halogenated C7-C20 alkylaryl groups; two R?1¿ groups can also form with the metal Mt one condensed ring. These compounds are useful as cocatalysts for polymerizing olefins. |