| abstract |
The invention relates to a diorganomagnesium compound having the formula RB-(Mg-RA)m-Mg-RB, where RB comprises a benzene ring substituted by the magnesium atom, one of the carbon atoms of the benzene ring in the ortho position of the magnesium is substituted by methyl, ethyl, isopropyl or forms a ring with the carbon atom that is its closest neighbour and is in a meta position of the magnesium, the other carbon atom of the benzene ring in the ortho position of the magnesium is substituted by a methyl, ethyl or isopropyl, RA is a divalent aliphatic hydrocarbon chain, interrupted or not by one or more oxygen atoms or sulphur or by one or more arylene groups, and where m is number greater than or equal to 1, preferably equal to 1. Used as a cocatalyst of a rare earth metallocene, the compound of the invention enables the synthesis of telechelic polymers. |