Development of Highly Functionalized Metal Nanocluster Catalysts for Fine Organic Synthesis

Heterogeneous catalysts are key players in environmentally benign organic synthesis because they can be easily recovered and reused by simple operations. In addition, heterogeneous catalysts can be applied to synthetic tools in next generation, such as flow systems and combinatorial synthesis. We have focused on metal nanocluster catalysts as highly active and robust heterogeneous catalysts and have developed variety of metal nanocluster catalysts for fine organic synthesis. In the course of development, we chose organic polymer as support of metal nanoclusters because organic polymer can provide efficient reaction environment for organic reactions and introduction of various functionality that provide synergistic effect to metal nanocluster catalyst is facile in organic polymers. In this context, we designed both supports and metal nanoclusters in order to realize not only high reactivity and selectivity but also different catalytic functions that cannot be achieved with homogeneous catalyst. This article describes the design and synthesis of highly functionalized metal nanocluster catalysts, namely polymer incarcerated metal nanocluster catalysts, and their application to aerobic oxidations, asymmetric reactions, tandem reactions and synergistic catalysis.