Design and development of iron-based non-precious metal catalyst systems

Precious metal compounds are widely used as catalysts in recent organic synthesis in both academic and industrial researches. Recently, development of new iron-based catalyst systems that can be a substitute of noble metal catalyst is desired from the point of view of scarcity of the element and the toxicity of the precious metal residue in the products. However, design and synthesis of iron catalysts is often difficult due to the existence of multiple spin states in close energy levels. In addition, instability of organoiron species toward air and moisture also prevents the synthesis of catalytically active iron species. In this paper is presented our recent effort to develop the efficient iron catalyst system. First, low-spin design of the iron catalyst that can catalyze the reaction involving two-electron redox pathway is investigated based on the strategy of construction of the disilaferracyclic complexes. Second, novel efficient and easy-to-handle iron catalyst system consisting of iron precursor and isocyanide ligands is developed for the hydrosi-lylation of alkenes.