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

• Published in: European Journal of Organic Chemistry Vol. 2009; no. 6; pp. 789 - 792
• Main Authors: Hirakawa, Takuya, Tanaka, Shinji, Usuki, Naoki, Kanzaki, Hisao, Kishimoto, Mikio, Kitamura, Masato
• Format: Book Review Journal Article
• Language: English
• Published: Weinheim WILEY‐VCH Verlag 01.02.2009; Wiley
• Subjects: Chemistry; Chemistry, Organic; Magnetic particles; Physical Sciences; Protecting groups; Ruthenium; Science & Technology; Supported catalysts; Sustainable chemistry; π‐Allyl complexes; ALLYLIC PROTECTING GROUPS; Ruthenium; BEHAVIOR; ENVIRONMENT; pi-Allyl complexes; CLEAVAGE; Supported catalysts; ALCOHOLS; NANOPARTICLES; RECOVERY; Magnetic particles; ETHERS; HYDROFORMYLATION CATALYSTS; Protecting groups; SILICA; Sustainable chemistry
• ISSN: 1434-193X; 1099-0690
• DOI: 10.1002/ejoc.200801166

The highly reactive and chemoselective homogeneousdeallylation catalyst CpRu(η3‐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. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) The new heterogeneous deallylation catalyst Fe3O4@SiO2–L–CpRu(η3‐C3H5) was prepared. It displays high saturation magnetization, weak coercive forces, and high dispersibility, and its utility was demonstrated by the deprotection of carboxylic acids, phosphoric acids, and alcohols in the synthesis of dipeptides and a triribonucleotide 3–5 U.