2012 年 70 巻 7 号 p. 711-721
Heterogeneous palladium catalysts have drawn much attention in organic synthetic and process chemistry from sustainable and industrial points of view due to their air-stability, recoverability, reusability, rare-residual property, and so on. Palladium on charcoal (Pd/C), which has been used as a common hydrogenation catalyst, is finding various applications including cross-coupling and deuterium (tritium) labeling reactions. However, the catalyst activity is sometimes supplier-or even lot-dependent, since the charcoal is derived from natural resources such as peat and sawdust, which produce difference in ultra-trace amount of inorganic impurities, pore sizes and surface areas. We demonstrate the development of a novel heterogeneous Pd and Cu catalysts supported on a commercial synthetic adsorbent, DIAION® HP20, and their application to the hydrogenation of a wide range of reducible functionalities, ligand-free cross-coupling reactions, such as Suzuki-Miyaura, Mizoroki-Heck and Sonogashira-type reactions and the azide-alkyne Huisgen cycloaddition. The distinct features of catalysts is the simple preparation, strong and efficient catalyst activity based on the lipotropy or hydrophobic effect of the support, wide applicability, recoverability by a simple filtration, and reusability.