Polymer-micelle incarcerated ruthenium catalysts for oxidation of alcohols and sulfides

Amine-containing diblock terpolymers via AROP: a versatile method for the generation of multifunctional micelles

We herein report the synthesis and block copolymerization via AROP of three glycidyl amine species (PiGA; OPGA, and MPGA) with different hydrophobicity. Micelles formed from these block copolymers respond to changes in pH and H₂O₂ concentration.

Advances in Synthetic Applications of Hypervalent Iodine Compounds

The preparation, structure, and chemistry of hypervalent iodine compounds are reviewed with emphasis on their synthetic application. Compounds of iodine possess reactivity similar to that of transition metals, but have the advantage of environmental sustainability and efficient utilization of natural resources. These compounds are widely used in organic synthesis as selective oxidants and environmentally friendly reagents. Synthetic uses of hypervalent iodine reagents in halogenation reactions, various oxidations, rearrangements, aminations, C-C bond-forming reactions, and transition metal-catalyzed reactions are summarized and discussed. Recent discovery of hypervalent catalytic systems and recyclable reagents, and the development of new enantioselective reactions using chiral hypervalent iodine compounds represent a particularly important achievement in the field of hypervalent iodine chemistry. One of the goals of this Review is to attract the attention of the scientific community as to the benefits of using hypervalent iodine compounds as an environmentally sustainable alternative to heavy metals.

Cooperative catalysis approach to intramolecular hydroacylation

Prior examples of hydroacylation to form six- and seven-membered ring ketones require either embedded chelating groups or other substrate design strategies to circumvent competitive aldehyde decarbonylation. A cooperative catalysis strategy enabled intramolecular hydroacylation of disubstituted alkenes to form seven- and six-membered rings without requiring substrate-embedded chelating groups.

Development of polysilane-supported palladium/alumina hybrid catalysts and their application to hydrogenation

Novel immobilized Pd catalysts, polysilane-supported palladium/alumina hybrid catalysts, have been developed. The catalysts showed high catalytic activity for hydrogenation, and could be used in an organic solvent or under solvent-free conditions.

Preparation of Phosphinated Polymer-Incarcerated Palladium and Its Application to CN and CC Bond-Forming Reactions

Phosphinated polymer-incarcerated (PI) Pd catalysts were prepared by immobilization of palladium with phosphinated polymers by using the PI method. The phosphinated PI Pd catalysts showed good catalytic activity without externally added phosphine ligands in the amination of aryl halides for C-N bond-forming reactions, as well as in Suzuki-Miyaura and Sonogashira coupling. No leaching of palladium from the immobilized Pd was observed by fluorescence X-ray analysis. Furthermore, it was found that immobilization of Pd by the PI process facilitated the suppression of poisoning of the metal by amines. These effects can be ascribed to stabilization of the catalyst by both the phosphine moieties and the benzene rings in the swollen polymer support. The phosphinated PI Pd catalysts could also be recovered by simple filtration and reused several times without leaching of palladium in both the amination and Suzuki-Miyaura coupling reactions.

Polysilane-supported Pd and Pt nanoparticles as efficient catalysts for organic synthesis

Polysilane-supported Pd and Pt catalysts have been prepared for the first time, and used successfully in hydrogenation, Suzuki and Sonogashira reactions, and hydrosilylation respectively: the reactions proceeded in high yields, and the catalysts could be recovered almost quantitatively by simple filtration and reused.

Novel immobilization method of enzymes using a hydrophilic polymer support

A novel immobilization of an enzyme with a hydrophilic polymer support in organic solvents has been developed utilizing the "polymer-incarcerated (PI) method", which has been used to immobilize metal catalysts; the kinetic resolution of secondary alcohols was found to proceed more smoothly using immobilized lipases (CALB) than free lipases.