A Magnetically Separable Heterogeneous Deallylation Catalyst: [CpRu(η3-C3H5)(2-pyridinecarboxylato)]PF6 Complex Supported on a Ferromagnetic Microsize Particle Fe3O4@SiO2

The highly reactive and chemoselective homogeneous deallylation catalyst CpRu(eta(3)-C3H5) (4-substituted-2-pyridinecarboxylato) was immobilized on microsize spherical Fe3O4@SiO2 particles. The resultant heterogeneous catalyst displays high saturation magnetization, weak coercive forces and high levels of dispersibility. The catalyst has increased the utility of deallylation by allowing the reaction to be conducted without extra additives. The only co-product of the reaction is a volatile allyl ether compound. Here, we demonstrate the efficient deallylation and separation of highly polar multifunctional compounds as well as multiple rounds of catalyst recycling without significant loss of reactivity. The usefulness of this catalyst has been confirmed by the synthesis of a triribonucleotide 3-5 U. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)