Patent ID: 8394737

Claim:
A method for preparing an activating support that comprises the steps of: a) providing a support prepared from silica or from mixed mineral oxides based on silica; b) grafting on the surface of the support of step a) a mixture of silylating agents comprising a functionalised silylating agent of formula Y 3 Si-L-NR′ 2 wherein each R′ is independently selected from alkyl, aryl, alkylaryl or alkylaryl, and a structurally similar non functionalised silylating agent Y 3 Si-L to provide a modified support, said functionalised and non functionalised silylating agents being in a ratio ranging between 1:1 and 1:19 and wherein each Y is independently selected from alkoxy, halogen or hydrogen, L is a phenyl group c) adding to the intermediate support of step b) a non-nucleophile trimethylsilylating agent selected from the group consisting of trimethylphenoxysilane, hexamethyldisiloxane, trimethylsilyl methanesulfonate, trimethylsilyl trifluoromethanesulfonate, trimethylsilyl-p-toluenesulfonate, hexamethyldisilazane, N,N-bis(trimethylsilyl)urea, N,O-bis(trimethylsilyl)acetamide, N-trimethylsilyl acetamide, N-methyl-N-trimethylsilyltrifluoroacetamide, N-trimethylsilylimidazole, N-trimethylsilylthiazole, N-trimethylsilyloxazole and a trialkylhalogensilane to form an intermediate support: d) protonating the intermediate support of step c) with an acid AH in order to form a protonated intermediate support: wherein A is triflate CF 3 SO 2 O (OTf) or halogen; e) adding a borate or aluminate XM to the protonated intermediate support of step d) wherein X is Al- or B-containing activating group and M is a metal Group 1 of the Periodic Table, to form an activating support: and f) retrieving the activating support.