Confinement of the Grubbs Catalyst in Alkene-Functionalized Mesoporous Silica

Grubbs I catalyst, [RuCl sub(2)(=C(H)(Ph))(PCy sub(3)) sub(2)], was incorporated into ordered mesoporous SBA-15 silica materials functionalised with alkenyltrichlorosilanes with different C chain lengths, e.g. vinyl- (C sub(2)), allyl- (C sub(3)), hexenyl- (C sub(6)) and octenyl- (C sub(8)) trichlorosilanes. The obtained materials, before and after interaction with Grubbs I, were characterised and the investigations revealed a pronounced dependence of the Grubbs catalyst stability on the alkyl chain length of the grafted moieties. The nature of the immobilised Ru-based species was a function of the surface modification, i.e. chain length of the alkenyl-silane.