The Sydney University Chemical Society with the The University of New South Wales Chemical Society present the second of the 2006 Howard Memorial Lectures at 6:30pm Thursday 17th August, 2006 in Room G25, Electrical Engineering, University of New South Wales. The speaker will be Professor Shu Kobayashi
Renaissance of Immobilized Metal Catalysts
Graduate School of Pharmaceutical Sciences
The University of Tokyo
Immobilized catalysts have been reinvestigated from two aspects; keys to environmentally benign chemical processes and high-throughput organic synthesis for combinatorial chemistry. While most of known polymer-supported catalysts are less active than the corresponding original catalysts, new types of polymer-supported catalysts, microencapsulated catalysts and polymer incarcerated catalysts, have been developed. The catalysts were immobilized onto polymers using physical envelopment by polymer backbones and interaction π electrons of benzene rings of the polystyrenes used as polymer backbones and vacant orbitals of the catalysts. Several metal catalysts (Sc, Os, Pd, Ru, Pt, etc.) have been successfully prepared and high activities have been attained in several reactions. In all cases, no leaching of the catalysts occurred, and the immobilized catalysts were recovered quantitatively by simple filtration and reused without loss of activity. Moreover, subnanometer Pd clusters stabilized within micelles of random copolymers were formed by direct immobilization of Pd(0) via ligand exchange. The clusters were estimated to contain approximately seven Pd atoms on average (cluster diameter, ca. 0.7 nm). These micelles containing Pd clusters were efficient catalysts for hydrogenations and Heck reactions. In this lecture, several excellent immobilized catalysts will be introduced. In addition, the application of these catalysts to microchannel systems will also be discussed.
Thursday 17th August at 5:30pm
Room G25, Electrical Engineering, University of New South Wales.